Biology Quiz 4

The smallpox vaccine is made from a virus called vaccinia, which is a poxvirus similar to smallpox, but less harmful. It contains live vaccinia virus, not a killed or weakened virus like many other vaccines. Other live virus vaccines currently used include measles, mumps, rubella, and chickenpox.

Barr body is the inactive X-chromosome in the somatic cells of mammalian females. Human females have two X chromosomes, while males have one X and one Y. In all of the female somatic cells, which don't take part in sexual reproduction, one of the X chromosomes is active, and the other is inactivated in a process called lyonization, becoming the Barr body.

The starfish has respiratory organ but does not have brain. They have a complex nervous system that allows them to make a decision. This nervous system is centralized in the ring around the mouth.

colour blindness, inability to distinguish one or more of the three colours red, green, and blue. A man with colour blindness will see red as Green.

The vector of disease sleeping sickness is tsetse fly. Sleeping sickness (African Trypanosomiasis) is caused by microscopic parasites of the species Trypanosoma brucei. It is transmitted by the tsetse fly (Glossina species).

The adult human brain weighs on average about 1200–1400 gm which is about 2% of the total body weight.

Iodoform (triiodomethane) is a yellow, crystalline solid belonging to the family of organic halogen compounds. It is used as an antiseptic component of medications for minor skin diseases.

Xenobiotics which are inherently resistant to microbial attack are called as Recalcitrant.

A diuretic, also called water pill, is a medicine which promotes the secretion of urine. It is a medication designed to increase the amount of water and salt expelled from the body as urine.

Yawning occurs when CO₂ concentration in the blood is high, and Oxygen (O₂) concentration is low. The yawn acts as a boost to the O₂ levels.