D.

prothoracic gland

Prothoracic gland is also known as moult gland in some arthropods and Y organ or ventral gland in crustaceans. It secretes moulting hormone called ecdysone or ecdysome, which is steroid and stimulates moulting or ecdysis during metamorphosis in insects.

B.

atmosphere

Sol- gel theory of amoeboid movement was first given by Hyman, later supported by Pantin (1923) and Mast (1926). According to this theory, amoeboid locomotion is due to change in the viscosity of cytoplasm.

C.

malleus, incus and stapes

The middle ear cavity in mammals characteristically contains a chain of three little bones or ear ossicles extending between the tympanic membrane and the fenestra ovalis. These are called malleus (hammer), incus (anvil) and stapes (stirrup) because of their characteristic shapes.

B.

ADH

Antidiuretic hormone (ADH) controls the tubular permeability and concentration of sodium in the extracellular fluid. It regulates the osmotic pressure of body fluids by causing the kidneys to increase water reabsorption.

It associates with the renal pressure system and then regulates the fluid volume of body through the agency of hypothalamic osmoreceptors.

D.

fibroin

Silk fibre is formed of two proteins namely fibroin and sericin.