Sertoli cells are characteristic of only mammalian testis for the nourishment of spermatozoan.

Hammerling proved that nucleus is the main controlling centre of cell while working on Acetabularia.

Kidney stones are commonly crystals of calcium oxalate and the patients are therefore, advised to avoid spinach, rhubarb and asparagus in their diet.

Respiration of frog is not very efficient as compared to mammals. The diaphragm is absent in frog whereas it is found in rabbit.

Iron is stored in bone marrow and liver in the form of ferritin and transferrin coming from food sources. They both are the important sites for the storage of iron.

Red muscles are the muscles in which dark bands or fibers are dominant, and they contain a large amount of myoglobin and mitochondria in it. Red muscle fibres are thin, dark red and possess a red haem protein called myoglobin. 

Pepsin acts in an acidic medium. The HCl present in the stomach provides the pH (1-2) necessary to ensure the activation of pepsinogen to active form pepsin.

Excitability, contractibility and toxicity are the properties of skeletal muscles. Rhythmicity is one of the property or feature of cardiac balance.

In mitosis, during late prophase or prometaphase, nuclear membrane completely disappear while mutant form is observed rarely.

Prolactin is the lactogenic hormone. It stimulates mammary growth and differentiation and milk production. Therefore, it indirectly controls growth.