A-Z Zoology Terms With Definitions – Zoology Glossary

Latest audio book

Zoology Terms Starting With A

  • Aestivation: A state of dormancy or torpor that some animals enter during hot or dry periods to avoid desiccation and extreme heat.
  • Altricial: Refers to animals that are born in an underdeveloped state and require significant parental care, such as birds that hatch blind and featherless.
  • Aposematism: The use of bright coloration or other warning signals by animals to indicate that they are toxic or unpalatable to predators.
  • Antenna: A pair of long, thin sensory appendages on the heads of insects, crustaceans, and some other arthropods, used for detecting environmental cues.
  • Amniotic Egg: An egg that contains a protective amnion, allowing reptiles, birds, and mammals to reproduce away from water.
  • Amphibian: A class of cold-blooded vertebrates that typically have an aquatic larval stage and a terrestrial adult stage, such as frogs, salamanders, and newts.
  • Annelid: A phylum of invertebrates that includes segmented worms like earthworms and leeches.
  • Arthropod: A large phylum of invertebrates that includes insects, arachnids, and crustaceans, characterized by an exoskeleton, segmented body, and jointed appendages.
  • Avian: Pertaining to birds; used to describe characteristics and behaviors specific to birds.
  • Asexual Reproduction: A type of reproduction in which an organism produces offspring without the involvement of a mate, resulting in genetically identical offspring.
  • Amphipod: A type of small crustacean with a laterally compressed body, commonly found in marine and freshwater environments.
  • Abyssal Zone: The deep ocean zone, typically below 2,000 meters, where light does not penetrate and conditions are extreme.
  • Abiotic: Refers to the non-living components of an ecosystem, such as temperature, water, and soil, that influence living organisms.
  • Apical: Refers to the tip or apex of an organism or structure, often used in describing the growth regions of plants or the ends of animal appendages.
  • Autotomy: The ability of certain animals to deliberately shed or amputate a body part, such as a tail, to escape from predators.
  • Axial Skeleton: The part of the skeleton that includes the skull, vertebral column, and rib cage, supporting the central axis of the body.
  • Aorta: The main artery that carries oxygenated blood from the heart to the rest of the body in vertebrates.
  • Amphibious: Capable of living both on land and in water, often used to describe animals like frogs, turtles, and certain mammals.
  • Aquatic: Relating to water; used to describe organisms that live in or around water, such as fish, amphibians, and aquatic plants.
  • Adaptation: A characteristic or trait that has evolved in an organism to enhance its survival and reproduction in a specific environment.

Zoology Terms Starting With B

  • Bilateral Symmetry: Symmetry in which the body can be divided into two equal halves along a single plane.
  • Biodiversity: The variety of life in the world or in a particular habitat or ecosystem.
  • Bioluminescence: The production and emission of light by a living organism.
  • Bipedal: Using two legs for walking.
  • Bivalve: A class of marine and freshwater mollusks with bodies enclosed by a shell consisting of two hinged parts.
  • Blastula: An early stage of embryonic development that consists of a hollow ball of cells.
  • Brood Parasitism: A reproductive strategy in which one species lays its eggs in the nest of another species.
  • Bryophyte: A group of non-vascular plants that includes mosses, liverworts, and hornworts.
  • Buccal Cavity: The mouth cavity.
  • Budding: A form of asexual reproduction in which a new organism develops from an outgrowth or bud on the parent.
  • Bursa: A fluid-filled sac that reduces friction between tissues of the body.
  • Baleen: A filter-feeding system inside the mouths of baleen whales.
  • Barbel: A slender, whisker-like sensory organ near the mouth of certain fish.
  • Basal Metabolic Rate: The rate at which an organism uses energy while at rest to maintain vital functions.
  • Batesian Mimicry: A form of mimicry in which a harmless species imitates the warning signals of a harmful species.
  • Benthic: Relating to the bottom of a sea or lake or to the organisms that live there.
  • Biotic: Relating to or resulting from living organisms.
  • Boreal: Relating to the northern region or the northern forest biome.
  • Brachiation: A form of locomotion used by some primates, involving swinging from branch to branch.
  • Brackish Water: Water that has more salinity than freshwater but less than seawater.
  • Brood: The young of certain animals, especially birds, produced at one hatching or birth.
  • Bryozoan: A phylum of aquatic invertebrate animals that form colonies.
  • Bursa of Fabricius: An organ in birds that is involved in the development of the immune system.
  • Byssus: A bundle of filaments secreted by certain mollusks for attachment to a surface.
  • Baleen Plate: A structure in the mouths of baleen whales used to filter food from water.
  • Benthic Zone: The ecological region at the lowest level of a body of water.
  • Biomass: The total mass of organisms in a given area or volume.
  • Biotic Factor: A living component that affects the population of another organism or the environment.
  • Boreal Forest: A forest biome characterized by coniferous trees and cold climates.
  • Brachiopod: A phylum of marine invertebrates with bivalve dorsal and ventral shells.

Zoology Terms Starting With C

  • Carnivore: An animal that feeds on other animals.
  • Cephalopod: A class of mollusks that includes squid, octopuses, and cuttlefish.
  • Chitin: A long-chain polymer found in the exoskeletons of arthropods and the cell walls of fungi.
  • Chordate: Animals that possess a notochord at some stage in their development.
  • Cilia: Hair-like structures that extend from the surface of many animal cells.
  • Cnidocyte: A specialized cell in cnidarians that contains a stinging organelle.
  • Coelom: A body cavity within animals that is lined with mesoderm.
  • Commensalism: A relationship between two organisms where one benefits and the other is neither harmed nor helped.
  • Coniferous: Trees that produce cones and have needle-like leaves.
  • Crustacean: A large class of arthropods that includes crabs, lobsters, and shrimp.
  • Cytoplasm: The material within a living cell, excluding the nucleus.
  • Cocoon: A silky case spun by the larvae of many insects for protection during the pupal stage.
  • Coccyx: The small, triangular bone at the base of the spinal column in humans and some other vertebrates.
  • Coccygeal: Pertaining to the coccyx.

Zoology Terms Starting With D

  • Dorsal: Referring to the upper side or back of an animal, often opposite to the ventral (belly) side.
  • Detritivore: An organism that feeds on dead organic material, particularly plant detritus.
  • Diphtheria: A bacterial infection affecting the mucous membranes, often spread between humans and animals.
  • Dentition: The arrangement, type, and number of teeth in a particular species or individual.
  • Diurnal: Describes animals that are active during the day and rest at night, opposite to nocturnal.
  • DNA (Deoxyribonucleic Acid): The molecule that carries genetic instructions used in the growth, development, functioning, and reproduction of all living organisms.
  • Digestive System: The system of organs responsible for breaking down food into nutrients that can be absorbed by the body.
  • Deuterostome: A group of animals, including vertebrates, where the anus forms before the mouth during embryonic development.
  • Diphyodont: An organism that has two successive sets of teeth, such as humans (milk teeth and permanent teeth).
  • Dominance: A behavioral condition in which one individual in a social group asserts control or influence over others.
  • Dimorphism: The occurrence of two different forms among the individuals of a species, usually referring to sexual dimorphism (differences between males and females).
  • Dugong: A large marine mammal, closely related to the manatee, known for grazing on underwater grasses.
  • Dodo: An extinct flightless bird that was endemic to the island of Mauritius.
  • Diploid: A cell or organism having two sets of chromosomes, one from each parent.
  • Diploblastic: Refers to animals that develop from two germ layers (ectoderm and endoderm) during embryonic development, such as jellyfish.
  • Detoxification: The process by which an organism removes or neutralizes toxins.
  • Dendrite: The branched projections of a neuron that receive signals from other neurons.
  • Decapod: A group of crustaceans, such as crabs, lobsters, and shrimp, characterized by having ten limbs.
  • Deforestation: The removal of large areas of forest, leading to habitat loss and changes in ecosystem dynamics.
  • Decomposer: An organism, typically bacteria or fungi, that breaks down dead or decaying organic material, recycling nutrients back into the ecosystem.

Zoology Terms Starting With E

  • Ecdysis: The process of shedding or molting the outer layer of skin, as seen in reptiles, insects, and other arthropods.
  • Echinoderm: A phylum of marine animals characterized by radial symmetry and a calcareous skeleton, including starfish and sea urchins.
  • Ectotherm: An organism that relies on external sources of heat to regulate its body temperature, commonly referred to as a cold-blooded animal.
  • Ecosystem: A community of living organisms interacting with their physical environment, functioning as a unit.
  • Ecotype: A genetically distinct population within a species that is adapted to specific environmental conditions.
  • Ectoparasite: A parasite that lives on the surface of its host, such as fleas or lice.
  • Efferent: Refers to nerves that carry impulses away from the central nervous system to effectors like muscles or glands.
  • Elasmobranch: A subclass of cartilaginous fish that includes sharks, rays, and skates.
  • Embryogenesis: The process by which an embryo forms and develops from a fertilized egg.
  • Endangered Species: A species at risk of extinction due to a significant decline in its population or habitat.
  • Endemic: Refers to a species that is native to a specific geographic area and found nowhere else.
  • Endoparasite: A parasite that lives inside the body of its host, such as tapeworms.
  • Endoskeleton: An internal skeleton made of bone or cartilage that provides support and protection to an organism.
  • Endosymbiosis: A symbiotic relationship in which one organism lives inside the body or cells of another organism.
  • Eocene: A geological epoch that occurred from about 56 to 34 million years ago, characterized by the emergence of modern mammals.
  • Epidermis: The outermost layer of cells covering an organism, particularly in animals and plants.
  • Epiphyte: A plant that grows on another plant for physical support but is not parasitic, often found in tropical rainforests.
  • Epithelium: A type of tissue that lines the surfaces and cavities of organs and structures throughout the body.
  • Erythrocyte: A red blood cell that carries oxygen from the lungs to the rest of the body.
  • Eutherian: A group of mammals characterized by having a placenta, which allows for a longer gestation period.
  • Exoskeleton: A rigid external covering that provides both support and protection to an organism, as seen in arthropods.
  • Extant: A term used to describe species that are still living and not extinct.
  • Extinct: A term used to describe species that no longer exist.
  • Extracellular Matrix: A complex network of proteins and other molecules that provides structural and biochemical support to surrounding cells.
  • Exudate: A fluid that leaks out of blood vessels into nearby tissues, usually as a result of inflammation.
  • Eusociality: The highest level of social organization in animals, where individuals of the same species cooperate in caring for the young, have a division of labor, and have overlapping generations.
  • Ecomorph: A form or structure of an organism that is adapted to a specific environmental niche.
  • Endotherm: An organism that generates its own heat to maintain its body temperature, commonly referred to as a warm-blooded animal.
  • Ectoderm: The outermost layer of cells or tissue in an embryo, which develops into the skin and nervous system.
  • Epidemiology: The study of the distribution and determinants of health-related states or events in populations, and the application of this study to control health problems.
  • Echolocation: The use of sound waves and echoes to determine the location of objects, used by animals such as bats and dolphins.
  • Electrophoresis: A technique used to separate molecules, such as DNA or proteins, based on their size and charge by applying an electric field.
  • Ecophysiology: The study of the physiological responses of organisms to their environment.
  • Erythropoiesis: The process of producing red blood cells in the bone marrow.
  • Eutrophication: The process by which a body of water becomes overly enriched with nutrients, leading to excessive growth of algae and depletion of oxygen.
  • Epizootic: A disease that occurs at a higher-than-normal rate within an animal population.
  • Endocrine Glands: Glands that secrete hormones directly into the bloodstream, such as the thyroid and adrenal glands.
  • Excretion: The process by which waste products of metabolism and other non-useful materials are eliminated from an organism.
  • Ecdysteroid: A group of hormones that play a role in molting and metamorphosis in arthropods.
  • Exuviae: The remains of an exoskeleton left behind after ecdysis or molting.

Zoology Terms Starting With F

  • Fertilization: The process by which male and female gametes unite to form a zygote, initiating the development of a new organism.
  • Filoplume: A type of feather found in birds, typically associated with sensory functions and located near the base of other feathers.
  • Fossorial: Refers to animals that are adapted to digging and living underground, such as moles.
  • Frugivore: An animal that primarily eats fruit.
  • Fungi: A kingdom of organisms that includes yeasts, molds, and mushrooms, which decompose organic matter and recycle nutrients in ecosystems.
  • Fasciola: A genus of parasitic flatworms, also known as liver flukes, that infect the livers of various mammals, including humans.
  • Fauna: The collective animal life of a particular region, habitat, or geological period.
  • Flagellum: A whip-like structure that enables certain cells, such as sperm or some single-celled organisms, to move.
  • Fibrinogen: A soluble plasma protein that is converted into fibrin during blood clotting.
  • Filter Feeder: An aquatic animal that feeds by filtering small particles or organisms from the water, such as whales or clams.
  • Follicle: A small secretory cavity, sac, or gland, such as a hair follicle or ovarian follicle.
  • Foregut Fermentation: A digestive process seen in some herbivores where fermentation of plant material occurs in a specialized stomach chamber before reaching the small intestine.
  • Formicidae: The scientific family name for ants, a diverse and widespread group of social insects.
  • Foramen: A natural opening or hole in a bone that allows the passage of nerves or blood vessels.
  • Fovea: A small pit or depression in the retina of the eye, where visual acuity is highest.
  • Fusiform: Spindle-shaped; tapering at both ends, commonly used to describe the body shape of certain fish and other animals.
  • Fecundity: The potential reproductive capacity of an individual or population, often measured by the number of eggs produced.
  • Forelimb: The front limb of an animal, equivalent to an arm or wing.
  • Flagellate: A type of protozoan that moves using one or more flagella.
  • Flight Feathers: The strong feathers on the wings and tail of birds that are essential for flight.
  • Furcula: Also known as the “wishbone,” it is a forked bone found in birds, formed by the fusion of two clavicles.
  • Facultative Parasite: An organism that can live both as a parasite and independently of a host.
  • Free-Living: Refers to organisms that do not rely on a host for survival, as opposed to parasitic organisms.
  • Fibrillation: Rapid, irregular, and unsynchronized contraction of muscle fibers, particularly in the heart.
  • Flatworm: A group of simple, soft-bodied invertebrates belonging to the phylum Platyhelminthes, many of which are parasitic.
  • Frontal Bone: The bone forming the front part of the skull and the upper part of the eye sockets.
  • Fusiform Muscle: A type of muscle that is spindle-shaped with a central belly that tapers toward both ends, found in certain limbs.
  • Fibrin: An insoluble protein formed from fibrinogen during the clotting of blood; it forms a fibrous mesh that impedes blood flow.
  • Fluke: A parasitic flatworm of the class Trematoda, typically found in the liver or lungs of vertebrates.
  • Fibrillation: Rapid, irregular contractions of muscle fibers, especially in the heart.
  • Fascia: A band or sheet of connective tissue that supports and surrounds muscles and other organs.
  • Femur: The thigh bone, the longest and strongest bone in the body, found in the hind limbs of vertebrates.
  • Flagellated Cell: A cell equipped with one or more flagella for movement or sensory functions.
  • Folivorous: Refers to animals that primarily consume leaves.
  • Fat Body: A tissue in insects and some other arthropods that stores nutrients and functions similarly to the liver in vertebrates.
  • Fovea Centralis: A small, central pit in the retina responsible for sharp central vision.
  • Fibrinogen: A plasma protein that is essential for blood clotting, converting into fibrin in response to injury.
  • Foetus: The developing offspring within the uterus of a mammal after the embryonic stage and before birth.
  • Foraging: The behavior of searching for and exploiting food resources.
  • Fossil: The preserved remains or traces of organisms from the past, typically found in sedimentary rocks.

Zoology Terms Starting With G

  • Gametogenesis: The process by which gametes (sex cells) are produced in an organism.
  • Ganglion: A structure containing a number of nerve cell bodies, typically linked by synapses.
  • Gastrovascular Cavity: A central cavity in some invertebrates that functions in both digestion and circulation.
  • Genotype: The genetic constitution of an individual organism.
  • Germ Layer: One of the three primary layers of cells (ectoderm, mesoderm, endoderm) in the embryo.
  • Gestation: The period of development from the fertilization of the egg to the birth of the offspring.
  • Gill: A respiratory organ found in many aquatic organisms that extracts oxygen from water.
  • Gizzard: A muscular, thick-walled part of a bird’s stomach for grinding food, typically with grit.
  • Glycogen: A form of stored glucose; primarily found in the liver and muscles.
  • Gnathostome: Jawed vertebrates.
  • Gonad: An organ that produces gametes; a testis or ovary.
  • Gonopore: An opening through which gametes are released.
  • Granivore: An animal that primarily eats seeds.
  • Gravid: Carrying eggs or young; pregnant.
  • Gregarious: Living in flocks or loosely organized communities.
  • Guard Hair: The long, coarse hair that forms the outer layer of an animal’s coat.
  • Gular: Pertaining to the throat.
  • Gymnosperm: A group of seed-producing plants that includes conifers.
  • Gynandromorph: An organism that contains both male and female characteristics.
  • Gynogenesis: A form of asexual reproduction that requires the presence of sperm but not its genetic contribution.
  • Gyrencephalic: Having a brain with convolutions or folds.
  • Gizzard: A muscular, thick-walled part of a bird’s stomach for grinding food, typically with grit.
  • Glycogen: A form of stored glucose; primarily found in the liver and muscles.
  • Gnathostome: Jawed vertebrates.
  • Gonad: An organ that produces gametes; a testis or ovary.
  • Gonopore: An opening through which gametes are released.
  • Granivore: An animal that primarily eats seeds.
  • Gravid: Carrying eggs or young; pregnant.
  • Gregarious: Living in flocks or loosely organized communities.
  • Guard Hair: The long, coarse hair that forms the outer layer of an animal’s coat.
  • Gular: Pertaining to the throat.
  • Gymnosperm: A group of seed-producing plants that includes conifers.
  • Gynandromorph: An organism that contains both male and female characteristics.
  • Gynogenesis: A form of asexual reproduction that requires the presence of sperm but not its genetic contribution.
  • Gyrencephalic: Having a brain with convolutions or folds.
  • Gizzard: A muscular, thick-walled part of a bird’s stomach for grinding food, typically with grit.
  • Glycogen: A form of stored glucose; primarily found in the liver and muscles.
  • Gnathostome: Jawed vertebrates.
  • Gonad: An organ that produces gametes; a testis or ovary.
  • Gonopore: An opening through which gametes are released.

Zoology Terms Starting With H

  • Habitat: The natural home or environment of an animal, plant, or other organism.
  • Hemoglobin: A protein in red blood cells that carries oxygen.
  • Herbivore: An animal that feeds on plants.
  • Hermaphrodite: An organism that has both male and female reproductive organs.
  • Hibernation: A state of inactivity and metabolic depression in endotherms.
  • Hindgut: The posterior part of the digestive system.
  • Homeostasis: The ability to maintain a stable internal environment.
  • Homologous Structures: Anatomical features that are similar in different species because of common ancestry.
  • Hominid: A member of the biological family Hominidae, which includes humans, chimpanzees, gorillas, and orangutans.
  • Hormone: A regulatory substance produced in an organism to stimulate specific cells or tissues into action.
  • Hybrid: The offspring of two plants or animals of different species or varieties.
  • Hydrostatic Skeleton: A structure found in many ectothermic organisms and soft-bodied animals consisting of a fluid-filled cavity, the coelom, surrounded by muscles.
  • Hyperplasia: An increase in the number of cells in an organ or tissue.
  • Hypothalamus: A region of the brain that controls body temperature, hunger, and other homeostatic systems.
  • Hemocoel: The primary body cavity of most invertebrates, containing circulatory fluid.
  • Heterotroph: An organism that cannot synthesize its own food and is dependent on complex organic substances for nutrition.
  • Heterozygous: Having two different alleles of a particular gene or genes.
  • Holometabolous: Undergoing complete metamorphosis, with distinct larval, pupal, and adult stages.
  • Homoeothermic: Maintaining a constant body temperature regardless of environmental temperature.
  • Humerus: The bone of the upper arm or forelimb.
  • Hydrophilic: Having an affinity for water.
  • Hydrophobic: Repelling water.
  • Hymenoptera: An order of insects that includes bees, wasps, and ants.
  • Hypoxia: A deficiency in the amount of oxygen reaching the tissues.
  • Hemiptera: An order of insects also known as true bugs, including aphids and cicadas.
  • Hepatic: Relating to the liver.
  • Heterocercal: Having unequal upper and lower lobes, typically referring to the tail fin of some fish.
  • Heterodont: Having teeth of different types.
  • Heterotrophic: Obtaining food by consuming other organisms.
  • Holoblastic: Referring to a type of cleavage in which the entire egg is divided into smaller cells.
  • Holotype: The single specimen upon which the description and name of a new species is based.
  • Humerus: The bone of the upper arm or forelimb.
  • Hydrophilic: Having an affinity for water.
  • Hydrophobic: Repelling water.
  • Hymenoptera: An order of insects that includes bees, wasps, and ants.
  • Hypoxia: A deficiency in the amount of oxygen reaching the tissues.
  • Hemiptera: An order of insects also known as true bugs, including aphids and cicadas.
  • Hepatic: Relating to the liver.
  • Heterocercal: Having unequal upper and lower lobes, typically referring to the tail fin of some fish.
  • Heterodont: Having teeth of different types.

Zoology Terms Starting With I

  • Ichthyology: The branch of zoology that deals with fishes.
  • Imago: The final and fully developed adult stage of an insect.
  • Immune System: The body’s defense system against infections and diseases.
  • Insectivore: An animal that primarily feeds on insects.
  • Instar: A developmental stage of arthropods, such as insects, between each molt until sexual maturity is reached.
  • Integument: The natural outer covering of an organism, such as skin or a shell.
  • Intertidal Zone: The area between the high tide and low tide marks.
  • Invertebrate: An animal lacking a backbone.
  • Iridophore: A type of chromatophore that reflects light, producing iridescent colors.
  • Isopod: A type of crustacean with a flattened body and seven pairs of legs.
  • Ichthyosaur: An extinct marine reptile that resembled a fish.
  • Immunology: The study of the immune system.
  • Incisor: A type of tooth adapted for cutting.
  • Indeterminate Growth: Growth that is not terminated; the organism continues to grow throughout its life.
  • Inflorescence: The arrangement of flowers on a plant.
  • Ingestive: Pertaining to the intake of food.
  • Insect: A class of arthropods with a three-part body, three pairs of legs, and usually two pairs of wings.
  • Insulin: A hormone that regulates blood sugar levels.
  • Integumentary System: The organ system that includes skin, hair, nails, and associated glands.
  • Intracellular: Located or occurring within a cell.
  • Intraspecific: Occurring within a species.
  • Invasive Species: A non-native species that spreads widely in a new habitat.
  • Iridescence: The phenomenon of certain surfaces that appear to change color as the angle of view or the angle of illumination changes.
  • Isogamy: A form of sexual reproduction involving gametes of similar morphology.
  • Isotope: Variants of a particular chemical element that differ in neutron number.
  • Isotonic: Having the same osmotic pressure as another fluid.
  • Ivermectin: A medication used to treat many types of parasite infestations.
  • Ichthyofauna: The fish population of a particular region.
  • Immunocompromised: Having an impaired or weakened immune system.
  • Incubation: The process of keeping eggs warm until they hatch.
  • Indigenous: Native to a particular region or environment.
  • Inoculation: The introduction of a pathogen or antigen into a living organism to stimulate the production of antibodies.
  • Insecticide: A substance used for killing insects.
  • Interbreeding: Breeding between individuals of different populations or species.
  • Intercellular: Located or occurring between cells.
  • Interneuron: A neuron that transmits impulses between other neurons.
  • Intraspecific Competition: Competition among members of the same species.
  • Invertebrate Zoology: The study of animals without backbones.
  • Irritability: The ability of an organism to respond to stimuli.
  • Isoptera: An order of insects that includes termites.

Zoology Terms Starting With J

  • Jacobson’s Organ: A chemoreceptor organ found in many animals, used for detecting pheromones.
  • Jellyfish: A free-swimming marine coelenterate with a gelatinous umbrella-shaped bell and trailing tentacles.
  • Jugular: Pertaining to the throat or neck.
  • Juvenile: The stage of an organism’s life cycle between the larval stage and adulthood.
  • Jugal Bone: A bone in the skull of vertebrates, also known as the cheekbone.
  • Jugal Arch: The bony arch of the cheek.
  • Jugal Point: The point where the jugal bone meets the maxilla.
  • Jugal Process: A projection of the jugal bone.
  • Jugal Suture: The joint between the jugal bone and the maxilla.
  • Jugal Symphysis: The junction where the two halves of the jugal bone meet.
  • Jugal Tubercle: A small rounded projection on the jugal bone.
  • Jugal Ridge: A raised line on the jugal bone.
  • Jugal Crest: A prominent ridge on the jugal bone.
  • Jugal Notch: A notch in the jugal bone.
  • Jugal Foramen: An opening in the jugal bone.
  • Jugal Fossa: A depression in the jugal bone.
  • Jugal Groove: A groove in the jugal bone.
  • Jugal Canal: A canal in the jugal bone.
  • Jugal Sinus: A cavity in the jugal bone.
  • Jugal Cavity: A hollow space in the jugal bone.
  • Jugal Plate: A flat part of the jugal bone.
  • Jugal Lamina: A thin layer of the jugal bone.
  • Jugal Septum: A partition in the jugal bone.
  • Jugal Spine: A spine-like projection on the jugal bone.
  • Jugal Tuberosity: A roughened area on the jugal bone.
  • Jugal Process of the Maxilla: A projection of the maxilla that articulates with the jugal bone.
  • Jugal Process of the Temporal Bone: A projection of the temporal bone that articulates with the jugal bone.
  • Jugal Process of the Zygomatic Bone: A projection of the zygomatic bone that articulates with the jugal bone.
  • Jugal Process of the Frontal Bone: A projection of the frontal bone that articulates with the jugal bone.
  • Jugal Process of the Parietal Bone: A projection of the parietal bone that articulates with the jugal bone.
  • Jugal Process of the Nasal Bone: A projection of the nasal bone that articulates with the jugal bone.
  • Jugal Process of the Lacrimal Bone: A projection of the lacrimal bone that articulates with the jugal bone.
  • Jugal Process of the Palatine Bone: A projection of the palatine bone that articulates with the jugal bone.
  • Jugal Process of the Vomer: A projection of the vomer that articulates with the jugal bone.
  • Jugal Process of the Sphenoid Bone: A projection of the sphenoid bone that articulates with the jugal bone.
  • Jugal Process of the Ethmoid Bone: A projection of the ethmoid bone that articulates with the jugal bone.
  • Jugal Process of the Inferior Nasal Concha: A projection of the inferior nasal concha that articulates with the jugal bone.

Zoology Terms Starting With K

  • Karyotype: The number and appearance of chromosomes in the nucleus of a eukaryotic cell, used to study genetic disorders.
  • Keratin: A fibrous protein that forms the main structural component of hair, feathers, claws, and the outer layer of skin.
  • Keystone Species: A species that plays a crucial role in maintaining the structure of an ecological community, affecting many other organisms in the ecosystem.
  • Kinesis: A non-directional movement response of an organism to a stimulus, where the speed of movement is related to the intensity of the stimulus.
  • Kin Selection: An evolutionary strategy that favors the reproductive success of an organism’s relatives, even at a cost to the organism’s own survival and reproduction.
  • Kidney: An organ in vertebrates that filters blood to remove waste products and produce urine.
  • Kleptoparasitism: A form of feeding where one animal takes food that another has caught or collected.
  • Krill: Small, shrimp-like marine crustaceans that are a key food source for many larger marine animals, such as whales.
  • Karyogamy: The fusion of two nuclei within a cell, typically occurring during fertilization.
  • Keratinocyte: A type of cell that makes up the majority of the epidermis, responsible for producing keratin.
  • Karyolysis: The dissolution or disintegration of a cell nucleus, often as a result of cell death.
  • Kinesis: A random movement of an organism in response to a stimulus, where the rate of movement changes with stimulus intensity.
  • Knot: A large flock of birds, especially shorebirds, that gather in a tight group.
  • Kelp: Large brown seaweeds (algae) that form underwater forests and provide habitat for many marine organisms.
  • Kin Recognition: The ability of an organism to distinguish between its relatives and non-relatives, often to avoid inbreeding.
  • Killer Whale: A large predatory marine mammal, also known as orca, that is part of the dolphin family.
  • Karyorrhexis: The fragmentation of a cell’s nucleus during cell death.
  • Keratinization: The process by which cells produce keratin and become part of the outermost layer of skin, hair, or nails.
  • Karyoplasm: The substance within the nucleus of a cell, also known as nucleoplasm.
  • Kangaroo Rat: A small, nocturnal rodent adapted to desert environments, known for its ability to survive without drinking water.
  • Krebs Cycle: A series of chemical reactions used by all aerobic organisms to generate energy through the oxidation of acetyl-CoA.
  • Karyomere: A small, membrane-bound structure containing a nucleus or part of a nucleus.
  • Koinobiont: A type of parasitoid that allows its host to continue growing after being parasitized, eventually killing it.
  • Karyotype Analysis: A laboratory technique used to visualize and analyze the number and structure of chromosomes in a cell.
  • K-strategist: An organism that produces fewer offspring, with a high investment in parental care, and typically has a longer lifespan.
  • Keratinous: Composed of or resembling keratin, such as the scales of reptiles or the beaks of birds.
  • Kinetic: Relating to or resulting from motion, often used to describe the movement of organisms in response to stimuli.
  • Kakapo: A large, flightless parrot native to New Zealand, known for its nocturnal habits and critically endangered status.
  • Kleptothermy: A behavior where an organism conserves energy by sharing body heat with others, such as reptiles basking together.
  • Karyogram: A diagram or photograph of an individual’s chromosomes arranged in homologous pairs.

Zoology Terms Starting With L

  • Larva: The immature, juvenile form of an animal that undergoes metamorphosis, typically found in insects, amphibians, and some other groups.
  • Lichen: A symbiotic association between a fungus and an alga or cyanobacterium, often found on rocks and trees.
  • Lipid: A group of naturally occurring molecules that include fats, oils, and hormones, essential for storing energy and forming cell membranes.
  • Litter: The offspring born at one time to a mammal, especially in species that have multiple births.
  • Lymph: A clear fluid that circulates through the lymphatic system, carrying cells that help fight infection.
  • Leukocyte: A white blood cell involved in the body’s immune response, defending against infections and foreign substances.
  • Lepidoptera: The order of insects that includes butterflies and moths, characterized by their scaled wings.
  • Lateral Line: A sensory organ in fish and some amphibians that detects vibrations and movements in the water.
  • Lithosphere: The rigid outer layer of the Earth, including the crust and upper mantle, where many organisms live.
  • Locomotion: The movement or ability to move from one place to another, essential for finding food, mates, and escaping predators.
  • Lysozyme: An enzyme that breaks down bacterial cell walls, found in many animal tissues and secretions, such as saliva and tears.
  • Lactation: The production and secretion of milk by female mammals to nourish their young.
  • Lignin: A complex organic polymer found in the cell walls of plants, providing structural support and protection.
  • Locus: The specific location of a gene or DNA sequence on a chromosome.
  • Lumbricus: A genus of earthworms, commonly found in soils, that play a key role in decomposing organic matter.
  • Leptocephalus: The transparent, leaf-shaped larval form of eels and some other fish.
  • Lophophore: A crown of ciliated tentacles found in certain invertebrate animals, used for feeding and respiration.
  • Lynx: A medium-sized wild cat known for its tufted ears, short tail, and solitary behavior, found in the northern hemisphere.
  • Limnetic Zone: The well-lit, open surface waters of a lake, away from the shore, where photosynthesis occurs.
  • Lateralization: The specialization of certain functions, such as speech or handedness, in one hemisphere of the brain.
  • Leptin: A hormone produced by fat cells that regulates energy balance by inhibiting hunger.
  • Lithophore: An organism that lives on or within rocks, often seen in harsh environments such as deserts.
  • Lophodont: Refers to molar teeth with ridged surfaces, adapted for grinding plant material, found in some herbivores.
  • Lysosome: A membrane-bound organelle in cells that contains enzymes for breaking down waste materials and cellular debris.
  • Lancelet: A small, elongated marine animal that is a member of the subphylum Cephalochordata, closely related to vertebrates.
  • Lotic: Pertaining to or living in flowing water, such as rivers and streams, as opposed to still water.
  • Labyrinth: A complex structure in the inner ear of vertebrates, involved in maintaining balance and hearing.
  • Lecithotrophic: Refers to embryos or larvae that are nourished by yolk rather than by a direct connection to the mother.
  • Leucism: A genetic condition resulting in reduced pigmentation, causing animals to appear pale or white, but not affecting the eyes.
  • Luminescence: The emission of light by a substance or organism, often seen in bioluminescent animals like fireflies and deep-sea creatures.

Zoology Terms Starting With M

  • Macrophage: A type of white blood cell that engulfs and digests cellular debris, foreign substances, and pathogens.
  • Mandible: The lower jawbone in vertebrates.
  • Mammal: A class of warm-blooded vertebrates characterized by the presence of mammary glands, hair, and three middle ear bones.
  • Marsupial: A subclass of mammals, most of which carry and nurse their young in a pouch.
  • Metamorphosis: A biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal’s body structure.
  • Mimicry: The resemblance of one organism to another or to an object in its surroundings for concealment and protection from predators.
  • Mitochondrion: An organelle found in large numbers in most cells, where the biochemical processes of respiration and energy production occur.
  • Mollusk: A large phylum of invertebrate animals that includes snails, slugs, mussels, and octopuses.
  • Monotreme: A primitive order of egg-laying mammals, including the platypus and echidna.
  • Morphology: The study of the form and structure of organisms and their specific structural features.
  • Mycology: The branch of biology concerned with the study of fungi.
  • Myelin: A fatty substance that surrounds the axon of some nerve cells, forming an electrically insulating layer.
  • Myofibril: A basic rod-like unit of a muscle cell.
  • Myriapod: A group of arthropods that includes centipedes and millipedes.
  • Myxomatosis: A disease caused by the Myxoma virus, affecting rabbits.
  • Macula: An oval-shaped pigmented area near the center of the retina in the human eye.
  • Malpighian Tubule: A type of excretory and osmoregulatory system found in some insects.
  • Mandibulate: Having mandibles or jaw-like structures.
  • Mantle: A significant part of the anatomy of mollusks, which secretes the shell.
  • Maxilla: The upper jawbone in vertebrates.
  • Melanin: A pigment that gives the skin, hair, and eyes their color.
  • Mesoderm: The middle layer of an embryo in early development.
  • Metabolism: The set of life-sustaining chemical reactions in organisms.
  • Microbiome: The collection of all the microorganisms living in association with the human body.
  • Microscope: An instrument used to see objects that are too small to be seen by the naked eye.
  • Mimic: An organism that resembles another organism or object.
  • Mitochondrial DNA: The DNA located in mitochondria, inherited only through the mother.
  • Molt: The process of shedding an old exoskeleton or skin to allow for growth.
  • Monogamy: A mating system in which one male mates with one female exclusively.
  • Mutualism: A type of symbiotic relationship where both species benefit.

Zoology Terms Starting With N

  • Nacre: Also known as mother-of-pearl, it is the iridescent substance forming the inner layer of the shell of some mollusks.
  • Nematode: A phylum of worms also known as roundworms.
  • Nephridium: An excretory organ in many invertebrates.
  • Neurotransmitter: Chemicals that transmit signals across a synapse from one neuron to another.
  • Niche: The role or function of an organism or species within an ecosystem.
  • Nidification: The process of building a nest.
  • Notochord: A flexible rod made out of a material similar to cartilage. If a species has a notochord, it is, by definition, a chordate.
  • Nucleus: The membrane-bound structure in a cell that contains the genetic material.
  • Nymph: An immature form of some invertebrates, particularly insects, which undergoes gradual metamorphosis before reaching its adult stage.
  • Nocturnal: Active during the night.
  • Neoteny: The retention of juvenile features in the adult animal.
  • Neurogenesis: The process by which new neurons are formed in the brain.
  • Neurotoxin: A toxin that acts on the nervous system.
  • Nictitating Membrane: A transparent or translucent third eyelid present in some animals.
  • Nidicolous: Referring to animals that stay in the nest for a long time after hatching.
  • Nidifugous: Referring to animals that leave the nest shortly after hatching.
  • Nematocyst: A specialized cell in the tentacles of a jellyfish or other coelenterate, containing a barbed or venomous coiled thread.
  • Nephrons: The functional units of the kidney.
  • Neuroglia: The supportive tissue of the nervous system.
  • Nematocyst: A specialized cell in the tentacles of a jellyfish or other coelenterate, containing a barbed or venomous coiled thread.
  • Neurolemma: The outermost nucleated cytoplasmic layer of Schwann cells that surrounds the axon of the neuron.
  • Neuroplasticity: The ability of the brain to change continuously throughout an individual’s life.
  • Nidicolous: Referring to animals that stay in the nest for a long time after hatching.
  • Nidifugous: Referring to animals that leave the nest shortly after hatching.
  • Nematocyst: A specialized cell in the tentacles of a jellyfish or other coelenterate, containing a barbed or venomous coiled thread.
  • Nephrons: The functional units of the kidney.
  • Neuroglia: The supportive tissue of the nervous system.
  • Neurolemma: The outermost nucleated cytoplasmic layer of Schwann cells that surrounds the axon of the neuron.
  • Neuroplasticity: The ability of the brain to change continuously throughout an individual’s life.
  • Nidicolous: Referring to animals that stay in the nest for a long time after hatching.

Zoology Terms Starting With O

  • Oogenesis: The process of egg cell (ovum) development in female animals.
  • Osmoregulation: The process by which animals regulate the balance of water and salts in their bodies.
  • Omnivore: An organism that eats both plant and animal matter.
  • Oviparous: Referring to animals that lay eggs, with little or no other embryonic development within the mother.
  • Ocelli: Simple eyes or eye-like spots found in some invertebrates, used to detect light and dark.
  • Operculum: A bony plate that covers the gills of fish, protecting them and aiding in respiration.
  • Ontogeny: The development of an individual organism from fertilization to maturity.
  • Olfaction: The sense of smell, used by many animals to detect odors in their environment.
  • Osteichthyes: A class of fish known as bony fish, characterized by a skeleton primarily composed of bone.
  • Osteocyte: A mature bone cell that maintains bone tissue.
  • Ornithology: The scientific study of birds.
  • Ommatidia: The individual visual units that make up the compound eyes of arthropods.
  • Osmosis: The movement of water molecules through a semi-permeable membrane from a region of lower solute concentration to higher concentration.
  • Oestrus: The period of sexual receptivity and fertility in female mammals, often referred to as being “in heat.”
  • Omohyoid: A muscle in the neck of vertebrates that plays a role in swallowing and speech.
  • Oral Disc: The mouth region in certain invertebrates, such as cnidarians, often surrounded by tentacles.
  • Osmoconformer: An organism that maintains its internal environment isosmotic to its external environment, common in many marine invertebrates.
  • Opisthosoma: The posterior part of the body in arachnids and some other arthropods, commonly referred to as the abdomen.
  • Olfactory Bulb: A neural structure involved in the sense of smell, located in the forebrain of vertebrates.
  • Operant Conditioning: A learning process through which the strength of a behavior is modified by reinforcement or punishment.
  • Oogenesis: The production of eggs or ova in female animals, typically occurring in the ovaries.
  • Ocellus: A small, simple eye found in invertebrates, capable of detecting light intensity but not forming images.
  • Osteology: The study of the structure and function of the skeleton and bones.
  • Ovoviviparous: Referring to animals that produce eggs that develop and hatch within the mother’s body, with the young being born live.
  • Orbital Cavity: The bony socket that contains the eye, also known as the eye socket.
  • Oocyte: An immature egg cell that undergoes development during oogenesis.
  • Osmotroph: An organism that absorbs dissolved organic compounds through osmosis, commonly seen in fungi and some protists.
  • Ossification: The process by which bone is formed, renewed, and repaired in animals.
  • Osteoblast: A type of cell responsible for bone formation.
  • Osmotic Pressure: The pressure required to prevent the flow of water across a semi-permeable membrane due to osmosis.

Zoology Terms Starting With P

  • Parasitism: A symbiotic relationship where one organism (the parasite) benefits at the expense of another (the host).
  • Pheromone: A chemical substance produced and released by an animal, affecting the behavior or physiology of others of its species.
  • Photosynthesis: The process by which plants, algae, and some bacteria convert light energy into chemical energy, producing oxygen as a byproduct.
  • Plankton: Small and microscopic organisms drifting or floating in the sea or freshwater, forming the base of many aquatic food chains.
  • Polymorphism: The occurrence of different forms, types, or morphs within a species, often seen in the coloration or structure of animals.
  • Predation: The act of one organism (the predator) hunting and consuming another organism (the prey).
  • Phylum: A major taxonomic group of animals or plants, ranking above class and below kingdom.
  • Pinniped: A member of the group of marine mammals that includes seals, sea lions, and walruses, characterized by their flippers.
  • Parthenogenesis: A form of asexual reproduction where an egg develops into an individual without fertilization.
  • Pelage: The fur, hair, or wool covering the body of a mammal.
  • Photoreceptor: A specialized cell or structure that responds to light, such as those found in the retina of the eye.
  • Plastron: The ventral (bottom) part of a turtle or tortoise shell.
  • Polygyny: A mating system in which a male has multiple female partners.
  • Phylogeny: The evolutionary history and relationships among individuals or groups of organisms.
  • Pinnate: Referring to a feather-like or compound structure with parts arranged on either side of a central axis, such as in the wings of birds.
  • Polymorphonuclear: Referring to white blood cells with a multi-lobed nucleus, such as neutrophils.
  • Pheromone: A chemical signal released by an animal that influences the behavior of other members of the same species.
  • Porifera: The phylum of aquatic invertebrates known as sponges, characterized by their porous bodies.
  • Plumage: The feathers covering a bird’s body, often used for flight, insulation, and display.
  • Proboscis: An elongated, flexible appendage on the head of an animal, used for feeding or sensing, as seen in insects like butterflies and mosquitoes.
  • Polyandry: A mating system in which a female has multiple male partners.
  • Protostome: A major group of animals characterized by the mouth forming before the anus during embryonic development.
  • Placenta: An organ that develops in the uterus during pregnancy in mammals, facilitating the exchange of nutrients and waste between mother and fetus.
  • Pectoral Fin: One of the paired fins located on the sides of a fish, used for steering and stabilization during swimming.
  • Photoperiodism: The physiological reaction of organisms to the length of day or night, affecting behaviors such as reproduction and migration.
  • Phagocytosis: The process by which a cell engulfs and digests solid particles, such as bacteria or debris, seen in immune cells like macrophages.
  • Plasmodium: A genus of parasitic protozoa that causes malaria in humans and other animals.
  • Prehensile: Capable of grasping or holding objects, often referring to tails or limbs in animals like monkeys and opossums.
  • Pupa: The life stage of some insects undergoing transformation between larva and adult, as seen in butterflies and beetles.
  • Parapodia: Paired, lateral appendages found in some annelid worms, used for locomotion and sometimes respiration.

Zoology Terms Starting With Q

  • Quadrate: A bone in the skull of most vertebrates that connects the jaw to the skull.
  • Quadriceps: A large muscle group that includes the four prevailing muscles on the front of the thigh.
  • Quadruped: An animal that walks on four legs.
  • Quarantine: A period of isolation to prevent the spread of disease.
  • Quaternary Structure: The structure formed by several protein molecules (polypeptide chains), usually called protein subunits.
  • Quill: The hollow, sharp spines of a porcupine or the large feathers of a bird.
  • Quorum Sensing: A system of stimuli and response correlated to population density.
  • Quiescence: A state of inactivity or dormancy.
  • Quillwort: A type of aquatic plant that resembles a quill.
  • Quokka: A small marsupial found in Australia.
  • Quoll: A carnivorous marsupial native to Australia and New Guinea.
  • Qubit: A unit of quantum information.
  • Quagga: An extinct subspecies of plains zebra.
  • Quinone: A class of organic compounds that are derived from aromatic compounds.
  • Quagga Mussel: An invasive species of freshwater mussel.
  • Quillwort: A type of aquatic plant that resembles a quill.
  • Quercetin: A plant pigment (flavonoid) found in many plants and foods.
  • Quillback: A type of freshwater fish.
  • Quercus: The genus of trees and shrubs commonly known as oaks.
  • Quinone: A class of organic compounds that are derived from aromatic compounds.

Zoology Terms Starting With R

  • Radial Symmetry: Symmetry around a central axis, as in a starfish or a tulip flower.
  • Radiata: A taxonomic rank used to classify animals with radial symmetry.
  • Radula: A tongue-like organ covered with teeth that mollusks use to scrape food into their mouths.
  • Raptor: A bird of prey, such as an eagle or hawk.
  • Receptor: A protein molecule that receives and responds to a neurotransmitter or hormone.
  • Recombination: The process by which genetic material is broken and joined to other genetic material.
  • Regeneration: The process of renewal, restoration, and growth.
  • Reptile: A class of cold-blooded vertebrates that includes snakes, lizards, crocodiles, and turtles.
  • Respiration: The process of inhaling oxygen and exhaling carbon dioxide.
  • Retina: The light-sensitive layer of tissue at the back of the inner eye.
  • Rhinoceros: A large, thick-skinned herbivorous mammal with one or two horns on its snout.
  • Ribosome: A complex molecular machine found within all living cells that produces proteins.
  • Rodent: A mammal of the order Rodentia, characterized by a single pair of continuously growing incisors in each of the upper and lower jaws.
  • Roe: The eggs of fish and certain marine animals.
  • Ruminant: A mammal that chews cud regurgitated from its rumen, such as a cow or sheep.
  • Raptor: A bird of prey, such as an eagle or hawk.
  • Receptor: A protein molecule that receives and responds to a neurotransmitter or hormone.
  • Recombination: The process by which genetic material is broken and joined to other genetic material.
  • Regeneration: The process of renewal, restoration, and growth.
  • Reptile: A class of cold-blooded vertebrates that includes snakes, lizards, crocodiles, and turtles.
  • Respiration: The process of inhaling oxygen and exhaling carbon dioxide.
  • Retina: The light-sensitive layer of tissue at the back of the inner eye.
  • Rhinoceros: A large, thick-skinned herbivorous mammal with one or two horns on its snout.
  • Ribosome: A complex molecular machine found within all living cells that produces proteins.
  • Rodent: A mammal of the order Rodentia, characterized by a single pair of continuously growing incisors in each of the upper and lower jaws.
  • Roe: The eggs of fish and certain marine animals.
  • Ruminant: A mammal that chews cud regurgitated from its rumen, such as a cow or sheep.
  • Raptor: A bird of prey, such as an eagle or hawk.
  • Receptor: A protein molecule that receives and responds to a neurotransmitter or hormone.
  • Recombination: The process by which genetic material is broken and joined to other genetic material.

Zoology Terms Starting With S

  • Species: The basic unit of biological classification, a group of organisms capable of interbreeding and producing fertile offspring.
  • Symbiosis: Interaction between two different organisms living in close physical association, typically to the advantage of both.
  • Spermatogenesis: The process by which sperm cells are produced and developed.
  • Sessile: Describes an organism that is fixed in one place; immobile.
  • Scavenger: An animal that feeds on dead or decaying organic matter.
  • Sclerite: A hardened body part or plate, often found in arthropods.
  • Siphon: A tube-like structure through which water enters and leaves the bodies of certain aquatic animals.
  • Spermatophore: A capsule or mass created by males of various species, containing spermatozoa and transferred to the female’s reproductive tract.
  • Subspecies: A taxonomic category that ranks below species, usually a fairly permanent geographically isolated race.
  • Saprozoic: Feeding on decaying organic matter.
  • Sclerotization: The process of hardening of the cuticle in arthropods.
  • Spicule: A small, needle-like structure found in sponges and other invertebrates.
  • Siphonophore: A colonial marine organism made up of specialized individual animals (zooids).
  • Spermatheca: A sac in the female reproductive system of some invertebrates where sperm is stored after mating.
  • Sclerophyll: A type of vegetation with hard leaves adapted to dry climates.
  • Saprobes: Organisms that obtain food from decaying organic matter.
  • Spermatocyte: A cell in the testes that undergoes meiosis to form spermatids.
  • Siphuncle: A tube-like structure in cephalopods used to regulate buoyancy.
  • Sclerite: A hardened body part or plate, often found in arthropods.
  • Spermatid: An immature male sex cell formed from a spermatocyte that can develop into a spermatozoon.
  • Saprozoic: Feeding on decaying organic matter.
  • Sclerotome: The part of a somite in a vertebrate embryo that gives rise to bone or other skeletal tissue.
  • Siphonoglyph: A ciliated groove in the pharynx of sea anemones and some corals.
  • Spermatogenesis: The process by which sperm cells are produced and developed.
  • Saprozoic: Feeding on decaying organic matter.
  • Sclerotization: The process of hardening of the cuticle in arthropods.
  • Spicule: A small, needle-like structure found in sponges and other invertebrates.
  • Siphonophore: A colonial marine organism made up of specialized individual animals (zooids).
  • Spermatheca: A sac in the female reproductive system of some invertebrates where sperm is stored after mating.
  • Sclerophyll: A type of vegetation with hard leaves adapted to dry climates.

Zoology Terms Starting With T

  • Taxonomy: The science of classification of organisms.
  • Trophic Level: The position an organism occupies in a food chain.
  • Tympanum: A membrane in the ear of some animals, such as frogs, that vibrates in response to sound waves.
  • Torpor: A state of decreased physiological activity in an animal, usually by a reduced body temperature and metabolic rate.
  • Tarsus: The part of the leg of an insect or other arthropod that is attached to the tibia.
  • Tegument: The outer body covering of certain invertebrates, such as nematodes.
  • Trophic Cascade: A series of changes in the population sizes of organisms at different trophic levels in a food chain, usually caused by the addition or removal of a key predator.
  • Tympanic Membrane: Another term for the eardrum.
  • Taxis: Movement of an organism in response to a stimulus such as light or the presence of food.
  • Trachea: The windpipe; a tube that connects the pharynx and larynx to the lungs.
  • Tendril: A slender, thread-like appendage of a climbing plant, often growing in a spiral form, that stretches out and twines around any suitable support.
  • Tuber: A thickened underground part of a stem or rhizome, serving as a food reserve and bearing buds from which new plants arise.
  • Tunic: A covering or layer of tissue, especially one that encloses an organ or body part.
  • Tympanum: A membrane in the ear of some animals, such as frogs, that vibrates in response to sound waves.
  • Torpor: A state of decreased physiological activity in an animal, usually by a reduced body temperature and metabolic rate.
  • Tarsus: The part of the leg of an insect or other arthropod that is attached to the tibia.
  • Tegument: The outer body covering of certain invertebrates, such as nematodes.
  • Trophic Cascade: A series of changes in the population sizes of organisms at different trophic levels in a food chain, usually caused by the addition or removal of a key predator.
  • Tympanic Membrane: Another term for the eardrum.
  • Taxis: Movement of an organism in response to a stimulus such as light or the presence of food.
  • Trachea: The windpipe; a tube that connects the pharynx and larynx to the lungs.
  • Tendril: A slender, thread-like appendage of a climbing plant, often growing in a spiral form, that stretches out and twines around any suitable support.
  • Tuber: A thickened underground part of a stem or rhizome, serving as a food reserve and bearing buds from which new plants arise.
  • Tunic: A covering or layer of tissue, especially one that encloses an organ or body part.
  • Tympanum: A membrane in the ear of some animals, such as frogs, that vibrates in response to sound waves.
  • Torpor: A state of decreased physiological activity in an animal, usually by a reduced body temperature and metabolic rate.
  • Tarsus: The part of the leg of an insect or other arthropod that is attached to the tibia.
  • Tegument: The outer body covering of certain invertebrates, such as nematodes.
  • Trophic Cascade: A series of changes in the population sizes of organisms at different trophic levels in a food chain, usually caused by the addition or removal of a key predator.
  • Tympanic Membrane: Another term for the eardrum.

Zoology Terms Starting With U

  • Ulna: One of the two long bones in the forearm, located on the side opposite the thumb.
  • Umbilical Cord: A flexible cord-like structure containing blood vessels that connects a fetus to the placenta.
  • Ungulate: A hoofed mammal.
  • Urea: A waste product formed in the liver, filtered out of the blood by the kidneys, and excreted in urine.
  • Ureter: A tube that carries urine from the kidney to the bladder.
  • Urethra: The duct through which urine is discharged from the bladder to the outside of the body.
  • Urinalysis: A test of urine to detect and manage a wide range of disorders.
  • Urochrome: A pigment that gives urine its yellow color.
  • Urogenital: Relating to the urinary and genital organs.
  • Urolithiasis: The formation of urinary stones.
  • Uropygium: The fleshy protuberance at the posterior end of a bird’s body, where the tail feathers are attached.
  • Urticaria: A skin condition characterized by red, itchy welts, also known as hives.
  • Uterus: The organ in female mammals where offspring are conceived and in which they gestate before birth.
  • Uvea: The middle layer of the eye, containing the iris, ciliary body, and choroid.
  • Uvula: The small fleshy extension at the back of the soft palate that hangs above the throat.
  • Ultrasound: Sound waves with frequencies higher than the upper audible limit of human hearing, used in medical imaging.
  • Ubiquitin: A small protein that tags other proteins for degradation.
  • Uropod: A posterior appendage in crustaceans used for swimming.
  • Urostyle: A long bone formed from fused vertebrae at the base of the vertebral column in some amphibians.
  • Uracil: One of the four nucleobases in the nucleic acid of RNA.

Zoology Terms Starting With V

  • Vacuole: A membrane-bound organelle in cells that stores nutrients, waste products, and other materials.
  • Vagus Nerve: A cranial nerve that controls heart rate, digestive tract, and other functions.
  • Vampire Bat: A bat species that feeds on the blood of other animals.
  • Vascular: Relating to the blood vessels or the circulatory system.
  • Vector: An organism that transmits a pathogen from one host to another.
  • Venom: A toxic substance produced by some animals, such as snakes and spiders, used to immobilize or kill prey.
  • Ventral: Pertaining to the underside or belly of an animal.
  • Vertebra: One of the series of small bones forming the backbone.
  • Vertebrate: An animal with a backbone.
  • Vestigial: Referring to an organ or part that is greatly reduced from the original ancestral form and is no longer functional or is of reduced or altered function.
  • Villi: Small, finger-like projections that extend into the lumen of the small intestine to increase surface area for absorption.
  • Viviparous: Giving birth to live young that have developed inside the body of the parent.
  • Vocal Cords: Folds of tissue in the throat that are key in creating sounds through vocalization.
  • Volvox: A genus of chlorophyte green algae that forms spherical colonies.
  • Vomer: A thin, flat bone forming part of the nasal septum.
  • Vulpine: Relating to or resembling a fox.
  • Ventral Fin: A fin located on the underside of a fish.
  • Vesicle: A small structure within a cell, consisting of fluid enclosed by a lipid bilayer.
  • Vibrissae: Whiskers or long, stiff hairs on the face of some mammals, used as tactile sensors.
  • Vermiform: Resembling or having the form of a worm.

Zoology Terms Starting With W

  • Worm: A general term for many different elongated, soft-bodied invertebrates, including annelids, nematodes, and flatworms.
  • Whiskers: Sensory hairs, also known as vibrissae, found on the faces of many mammals, used to detect nearby objects.
  • Wattle: A fleshy, often brightly colored piece of skin hanging from the neck or throat of some birds and mammals.
  • Weaning: The process by which a young mammal gradually transitions from mother’s milk to solid food.
  • Wingspan: The distance from the tip of one wing to the tip of the other wing in birds, bats, or insects.
  • Waterfowl: Birds that live on or around water, including ducks, geese, and swans.
  • Whale: A large marine mammal of the order Cetacea, characterized by a streamlined body, flippers, and a blowhole for breathing.
  • Wildebeest: A large antelope of the genus Connochaetes, native to Africa, known for its annual migration.
  • Woodpecker: A bird of the family Picidae, known for pecking at wood to find insects and create nesting sites.
  • Wormhole: A term used in zoology to describe the burrows or tunnels created by worms and other burrowing animals.
  • Webbing: The skin that connects the toes of certain animals, such as ducks, frogs, and bats, aiding in swimming or flight.
  • Wing: A specialized limb found in birds, bats, and insects, adapted for flight.
  • Water Strider: An insect of the family Gerridae, known for its ability to walk on the surface of water.
  • Whiptail: A lizard of the genus Cnemidophorus, known for its long, slender tail.
  • Wool: The soft, curly hair of sheep and some other mammals, used as a textile fiber.
  • Whelp: A term for the young of certain carnivorous mammals, such as wolves or dogs.
  • Wasp: An insect of the order Hymenoptera, often known for its narrow waist and sting.
  • Whale Shark: The largest species of shark and the largest living fish, known for its filter-feeding habits.
  • Wallaby: A small or mid-sized marsupial of the family Macropodidae, similar to kangaroos.
  • Worm Cast: The soil or sand excreted by earthworms, often seen as small mounds on the ground.

Zoology Terms Starting With X

  • Xylem: The tissue in vascular plants responsible for the conduction of water and nutrients from the roots to the rest of the plant.
  • Xenarthra: A superorder of placental mammals that includes armadillos, sloths, and anteaters, characterized by extra joints in their vertebral columns.
  • Xiphoid Process: The small, cartilaginous extension of the lower part of the sternum in vertebrates, often becoming ossified in adults.
  • Xenograft: A transplant of tissues or organs between different species, often used in medical research.
  • Xenopus: A genus of African aquatic frogs, often used as a model organism in biological research.
  • Xenobiotic: A chemical substance that is foreign to the biological system, often referring to pollutants or drugs.
  • Xanthophyll: A yellow pigment found in the leaves of plants and in the feathers of some birds, contributing to coloration.
  • Xenophagy: The consumption of foreign or unusual food, often observed in certain animal species.
  • Xiphosura: An order of arthropods that includes horseshoe crabs, known for their hard, horseshoe-shaped carapace.
  • Xenodiagnosis: A method of diagnosing parasitic infections by exposing a vector (such as an insect) to a potentially infected host and then examining the vector for the presence of the parasite.
  • Xerus: A genus of ground squirrels found in Africa, known for their burrowing behavior.
  • Xanthelasma: A condition characterized by yellowish deposits of fat underneath the skin, often around the eyes.
  • Xenotime: A rare earth phosphate mineral sometimes studied in paleontology and geology for its fossil content.
  • Xanthophores: Cells that contain yellow pigments, contributing to the coloration of fish, amphibians, and reptiles.
  • Xenogamy: Cross-pollination between flowers of different plants, a term also applicable in animal reproduction involving different species.
  • Xiphosuran: Refers to the group of marine arthropods within the order Xiphosura, commonly known as horseshoe crabs.
  • Xenopus laevis: A species of African clawed frog widely used as a model organism in developmental biology and genetics.
  • Xiphoid: Resembling a sword; often referring to anatomical structures with a pointed or elongated shape, like the xiphoid process.
  • Xenotransplantation: The transplantation of organs or tissues between different species, such as from animals to humans.
  • Xylophagy: The feeding behavior of certain animals, like termites and some beetles, that consume wood as their primary food source.

Zoology Terms Starting With Y

  • Yolk: The nutrient-rich portion of an egg, which provides nourishment to the developing embryo.
  • Yolk Sac: A membranous sac attached to an embryo, providing early nourishment in many vertebrates.
  • Yeti Crab: A type of deep-sea crab known for its hairy pincers, found near hydrothermal vents.
  • Yellow Perch: A species of freshwater fish, native to North America, known for its distinctive yellow and green coloration.
  • Yellow Fever: A viral disease transmitted by mosquitoes, affecting primates and humans, characterized by jaundice.
  • Y Chromosome: The sex chromosome typically associated with male characteristics in many animals, including humans.
  • Yolk Plug: A structure formed during the development of amphibians, where the yolk is partially exposed on the surface of the embryo.
  • Yersinia: A genus of bacteria, some species of which are known to cause diseases such as the plague.
  • Yellow Jacket: A type of wasp known for its aggressive behavior and painful sting, often found in North America.
  • Yolk Stalk: A tubular structure that connects the yolk sac to the embryo, providing nutrients during early development.
  • Yak: A long-haired domesticated bovid found in the Himalayan region, known for its ability to survive in high altitudes.
  • Yolkless Egg: An egg that lacks a yolk, often seen in some parasitic animals or certain species of fish.
  • Yearling: An animal that is one year old, particularly used to describe young horses or cattle.
  • Yellow-Bellied Marmot: A species of marmot native to the mountainous regions of North America, recognizable by its yellowish belly.
  • Yolk Protein: A type of protein found in the yolk of eggs, providing essential nutrients to the developing embryo.
  • Yellow-Billed Cuckoo: A bird species known for its distinctive yellow bill and migratory behavior in North America.
  • Ypsiliform: Shaped like the letter Y; used to describe certain anatomical structures in animals.
  • Yellowfin Tuna: A species of tuna known for its bright yellow fins, commonly found in tropical and subtropical oceans.
  • Yank: A sudden pull or jerk, sometimes used to describe the quick movements of animals in response to stimuli.
  • Yaffle: The characteristic call of the green woodpecker, often used to describe the bird’s laughing-like sound.

Zoology Terms Starting With Z

  • Zoology: The scientific study of animals, including their behavior, structure, physiology, classification, and distribution.
  • Zooplankton: Tiny floating animals, including both larval stages and adult forms, that drift in water bodies.
  • Zygote: The cell formed by the fusion of two gametes, marking the beginning of a new organism’s development.
  • Zoonosis: A disease that can be transmitted from animals to humans.
  • Zygodactyl: A foot structure in birds where two toes face forward and two face backward, as seen in parrots.
  • Zooxanthellae: Symbiotic algae that live within the tissues of corals, providing them with energy through photosynthesis.
  • Zebra: A species of African equids known for their distinctive black-and-white striped coats.
  • Zonary Placenta: A type of placenta characterized by a belt-like zone of attachment between the mother and fetus, found in some carnivores.
  • Zygomatic Arch: The bony arch on the side of the skull, beneath the eye, formed by the zygomatic bone and other bones.
  • Zoogeography: The study of the geographical distribution of animal species and populations on Earth.
  • Zymogen: An inactive enzyme precursor that requires a biochemical change to become an active enzyme.
  • Zygospore: A thick-walled resting spore formed by the fusion of two similar gametes in some fungi and algae.
  • Zebrafish: A small freshwater fish species used as a model organism in biological research due to its genetic similarity to humans.
  • Zonotrichia: A genus of sparrows, known for their distinctive songs and wide distribution in the Americas.
  • Zoophagy: The practice of feeding on other animals, a term often used to describe carnivorous plants and animals.
  • Zygomatic Bone: The bone that forms the prominent part of the cheek and contributes to the orbit of the eye.
  • Zosteropidae: A family of birds known as white-eyes, characterized by a distinctive ring of white feathers around their eyes.
  • Zonation: The distribution of different plant and animal species in distinct horizontal layers or zones, especially in ecosystems like mountains and oceans.
  • Zoospore: A motile, flagellated spore found in some algae, fungi, and protozoa, capable of movement.
  • Zygomorphic: Referring to flowers or other structures that are symmetrical along one plane only, often seen in orchids and some animals.

Latest Questions

Start Asking Questions

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Adblocker detected! Please consider reading this notice.

We've detected that you are using AdBlock Plus or some other adblocking software which is preventing the page from fully loading.

We don't have any banner, Flash, animation, obnoxious sound, or popup ad. We do not implement these annoying types of ads!

We need money to operate the site, and almost all of it comes from our online advertising.

Please add biologynotesonline.com to your ad blocking whitelist or disable your adblocking software.

×