Biology Test 223

The protienous part of an enzyme is known as apoenzyme.

Active site of an enzyme is formed of R - group of selected amino acid Because R - group of amino acid is variable part of amino acid . Which make bond with substrate & weaken the bond of substrate & form products .

A small Km indicates that the enzyme requires only a small amount of substrate to become saturated. Hence, the maximum velocity is reached at relatively low substrate concentrations. A large Km indicates the need for high substrate concentrations to achieve maximum reaction velocity.

Meiosis was discovered and described for the first time in sea urchin eggs in 1876 by the German biologist Oscar Hertwig. It was described again in 1883, at the level of chromosomes, by the Belgian zoologist Edouard Van Beneden, in Ascaris roundworm eggs.The term meiosis was introduced by Farmer and Moore

The rough endoplasmic reticulum is especially prominent in cells such as hepatocytes. The smooth endoplasmic reticulum lacks ribosomes and functions in lipid synthesisand metabolism, the production of steroid hormones, and detoxification. The smooth ER is especially abundant in mammalian liver and gonad cells.

Axon is sorrounded by sheath called (neurolemma) of special connective tissue called Schwann cell and ensheathed axon is called nerve fibre

In science, the extracellular matrix (ECM) is a collection of extracellular atoms emitted by cells that give auxiliary and biochemical help to the encompassing cells. Bones in our body are living tissue.

The animals in the Arctic and Antarctic lives there because of their layers of blubber, which is adipose tissue. The camel's hump is not a water storage organ but a thick hump of fat containing adipose tissue to protect the animal's internal organ from the heat of the desert. 

Although the hyoid bone is free-floating, it is not technically a sesamoid bone. All sesamoid bones form directly from the connective tissue found in tendons and ligaments. By contrast, the hyoid bone forms from a cartilaginous precursor like most other bones in the body.

1) Oxyntic cell (parietal cell): secrete HCl.

2) Goblet cell secret mucus

3) Chief cell secret prorennin and pepsinogen both are proenzyme

4) Hepatic cell secret Bile.