Answer:
Carbon's characteristics include its ability to bond with oxygen, hydrogen, nitrogen, phosphorus and sulfur.
Explanation:
Carbon biochemical compounds are essential to all life on the planet. Because of its bonding ability, carbon can form single, double, or triple covalent bonds with other atoms.
Answer:
Pepsinogen is produced by chief cells and is activated by hydrochloric acid secreted by parietal cells.
Explanation:
Pepsinogen is a proenzyme produced in the chief cells (that are located in the stomach lining) that, when gets activated, is transformed into pepsin - a peptidase with the function to degrade proteins into amino acids.
The reason why pepsinogen is released inactive is that it would break down all of the cell's proteins because of its proteolytic nature. For this reason, it is released as a proenzyme and gets activated when reaches the acidic environment provided by the hydrochloric acid secreted by the parietal cells, also in the stomach lining.
If you meant "distributed" and not "disturbed" it is distributed through the water/ hydrologic cycle.
Answer:
The correct answer is a) It brings a transport liquid into close contact with all cells in the body.
Explanation:
The circulatory system helps in bringing the blood which is a transport liquid in close contact with the cells present in our body. This helps in gas exchange between cells and blood. The circulation of blood in the body occurs by the pumping of blood by the heart into arteries, veins, and capillaries.
This circulation of blood plays many other vital functions like transport of nutrients to the cells, transport of waste products from the cell to outside the body, transport of hormones, maintenance of body temperature, etc.
So all these processes become possible when transport liquid comes in contact with the cells. Therefore the right answer is a.
