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What is gametogenesis? Gametogenesis Definition Gametogenesis is the biological process through which precursor cells undergo cell division and differentiation to form mature sex cells or gametes. Spermatogenesis 1. Formation of Spermatids Primary germinal cells or primordial cells refer to the male germinal cells that create sperm. The primordial cells undergo the following three steps in … Read more
Fertilization Definition External and Internal Fertilization Fertilizin and Antifertilizin Fertilizin Antifertilizin Process of Fertilization The two sequential steps of the fertilisation process are as follows: 1. The egg’s activation; 2. The amphimixis. 1. Activation of the Egg The process of activation of eggs is completed in following stages : (i) Movement of the sperm towards … Read more
Necrosis refers to irreversible cell damage and subsequent cell death resulting from pathogenic processes. It is an uncontrolled cell death that leads to enlargement of the cell organelles, plasma membrane rupture and final lysis of the cell, and intracellular contents leaking into the surrounding tissue, resulting in tissue injury. Unlike programmed cell death known as … Read more
Definition of Antimicrobial Agent Antimicrobial agent refers to those chemical or physical agents which are used to kill microorganisms or prevent their growth. There are present several types of microorganism which are responsible for infection or disease in animal or human body such as fungi, bacteria, virus, etc. Similarly, there are present different types of … Read more
What is a Signal Transduction Pathway? Definition of Signal Transduction Pathway A signal transduction pathway is a series of molecular events inside a cell that converts an external signal into a specific cellular response. Components of signal transduction Signal transduction involves several key components that are common in both plants and animals. These components include: … Read more
Virulence Definition Virulence define the intensity of a pathogen to cause disease. The Virulence varies among different microbial species. Virulence enables the microorganism to carry a specific character which can damage the tissue of the host cell. Virulence helps the microorganism to better survive its residency in the host. The virulence property of an organism varies … Read more
The Davson Danielli model (or the paucimolecular model) was an illustration that depicts the membrane in cells. It was developed in the year 1935 by Hugh Davson and James Danielli The model is a bilayer of phospholipids which is located within two layers of protein globular. the model is trilaminar as well as lipoproteinous.
Mesosomes and chondrioids are foldable into invaginations of the plasma membranes of bacteria. They are made through chemical fixation techniques that are used to prepare samples for electron microscopy.
Lysosomes are membranous, spherical sacs that are made up of enzymes. They are acidic hydrolase enzymes that are capable of digesting cellular macromolecules. The membrane of the lysosome helps keep its internal compartments acidic, and also separates the digestion enzymes and the cells’ other components. Lysosome enzymes are created by the proteins of the endoplasmic reticulum , which is then enclosed in vesicles created by the Golgi system. Lysosomes are created by budding out of in the Golgi complex.
What are Inclusion Bodies? Inclusion bodies are thick in size, spherical and aggregated proteins typically found inside the cells of protokaryotes thanks to the overexpression of heterologous proteins. Inclusion bodies comprise small particles that are freely suspended and floating in the cell wall. This is why they are also known as inclusions of the cytoplasm. … Read more
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