Bio

Hive of Honey Bee

Hive is the house of honey bee, constructed by the worker bees with the help of wax, resin and gum. Wax is secreted from the wax gland present in the abdomen of the worker bees. Resin and gums are collected from different trees by the worker bees. The hive of honey bee compose of a …

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Structure and function of ribosomes

Ribosomes are minute spherical membrane less cytoplasmic organelles present in both prokaryotic and eukaryotic cells consisting of RNA and some special proteins and perform the key role in protein synthesis. Ribosomes are usually designated according to their rate of sedimentation. Structure and function of ribosomes is described bellow. Ribosomes contain 80-85% of the cell’s ribonucleic …

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Type IV Hypersensitivity reaction and it’s mechanism

Type IV hypersensitivity reaction result from inappropriate T-cell activation. It takes at least 3 days to develop its action for this reason it is also called delayed type hypersensitivity (DTH). It is the only hypersensitivity category, that is purely cell mediated rather than antibody mediated. Mentioned disorders: Contact dermatitis, Chronic transplant rejection, Multiple sclerosis, Granuloma …

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Type III Hypersensitivity Reaction and it’s Mechanism

In type III hypersensitivity reaction, antigen-antibody complex deposited on host cells induces complement fixation and enhance inflammatory reaction. It is mainly mediated by Ig-G antibodies complement protein and neutrophils. The reaction of antibodies with the soluble antigens, generates immune complexes. Generally, these reactions facilitate the clearance of antigens by phagocytes But some times the presence …

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