What is Menstrual Cycle? Definition of Menstrual Cycle The menstrual cycle is a monthly series of physiological changes in the female reproductive system, characterized by the maturation and release of an ovum from the ovaries and the preparation of the uterine lining for potential implantation of a fertilized egg. If fertilization does not occur, the … Read more
What is Sperm Cell? Definition of Sperm Cell A sperm cell, or spermatozoon, is the male reproductive cell in sexual reproduction, produced in the testes through the process of spermatogenesis. It is a haploid cell containing half the number of chromosomes and is designed to fertilize a female egg cell, leading to the formation of … Read more
What is Skin? Definition of Skin Skin is the body’s largest organ, serving as a protective outer layer that covers and shields internal organs, muscles, and bones. It regulates body temperature, enables sensory perception, synthesizes vitamins, and acts as a barrier against pathogens and environmental damage. Gross Structure of Skin The skin’s composition varies across … Read more
What is Double Circulation? Types of Circulatory Systems In the animal kingdom, circulatory systems are fundamental for the transport of nutrients, gases, and waste products. There are primarily two types of circulatory systems: the open circulatory system and the closed circulatory system. Each of these systems has distinct mechanisms and efficiency levels, catering to the … Read more
Human teeth play a crucial role in the process of digestion, enabling the breakdown of food into smaller, manageable pieces before swallowing. Unlike some animals that can consume food in one large gulp, humans rely on their teeth to perform various functions essential for effective mastication. This article provides an overview of the structure, types, … Read more
What is Lung? Location of Lungs The lungs are essential respiratory organs located symmetrically on either side of the thoracic cavity. Their specific positioning and anatomical features enable efficient gas exchange within the body. Structure of Lung The lungs are vital organs characterized by their roughly cone-shaped structure. They exhibit a unique anatomy that facilitates … Read more
What is Urethra? Definition of Urethra The urethra is a tube that carries urine from the bladder to the outside of the body. In males, it also transports semen during ejaculation. Structure of Urethra The urethra is a fibrous and muscular tube that serves as the conduit for urine from the urinary bladder to the … Read more
What is Smooth Muscle? Definition of Smooth Muscle Smooth muscle is an involuntary, non-striated muscle tissue found primarily in the walls of hollow organs and blood vessels, responsible for functions such as regulating blood flow and propelling substances through organs. Characteristics of smooth muscle Smooth muscle tissue, distinct from its skeletal and cardiac counterparts, exhibits … Read more
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