Explanation

• Coronaviruses get their name from the crown-like shape of the viral particles, which have a distinctive "corona" or halo of protein spikes on their surface.
• These spikes give the virus its characteristic appearance under an electron microscope, resembling a crown or a halo.
• This is why the name "coronavirus" was chosen, as it reflects the virus's unique morphology.

Explanation

The epididymis is a tube-like structure located behind each testicle where sperm cells are stored, matured, and nourished before being transported to the vas deferens and eventually ejaculated.

Explanation

• In protein synthesis, the initiation of a polypeptide chain is typically started by an amino acid called methionine (Met).
• This is because methionine has a special tRNA (transfer RNA) that recognizes the start codon (AUG) on the mRNA (messenger RNA) and initiates protein synthesis.

Explanation

• Flukes (trematodes) and tapeworms (cestodes) are both types of parasitic flatworms (Platyhelminthes).
• They have a well-developed reproductive system, which allows them to produce large numbers of eggs and reproduce effectively in their host organisms.

Explanation

• Fishes are the first formed Chordates, which is a phylum of animals that includes vertebrates (animals with backbones) and some invertebrates (animals without backbones).
• Chordates are characterized by the presence of a notochord (a flexible, rod-like structure that provides support and stiffness) at some stage in their development.

Explanation

• The mesoglea is a thin, gelatinous layer of tissue in Hydra that lies between the outer epidermis and the inner gastrodermis.
• It is a cell-free, acellular layer that provides structural support and flexibility to the body.
• The mesoglea is composed of a matrix of glycoproteins and proteoglycans, but it does not contain any cells.

Explanation

• Turner's syndrome is a genetic disorder caused by a monosomy, where a person has only one copy of the X chromosome (45,X or 45,X0) instead of the usual two (46,XX or 46,XY).
• This results in a range of physical and developmental abnormalities.

Explanation

• Ticks and mites are members of the subclass Acari, which is a group of tiny arachnids that includes many parasitic species.
• Ticks are ectoparasites that feed on the blood of animals and humans, while mites include both free-living and parasitic species, with some feeding on skin, blood, or other bodily secretions.

Explanation

• Phylloquinone, also known as Vitamin K1, is essential for blood coagulation in the body.
• It plays a crucial role in the production of clotting factors II, VII, IX, and X, which are necessary for the formation of blood clots and stopping bleeding.

Explanation

Glycagon is a polypeptide hormone secreted by the pancreas (specifically, by the alpha cells of the islets of Langerhans) that raises blood glucose levels by stimulating the liver to convert stored glycogen to glucose and release it into the bloodstream.