Answer:
The correct option is<u> slight increase in salt concentration in the
</u>
<u>environment.</u>
Explanation:
The main function of contractile vacuole in the body of a paramecium is to pump out excess water. But an increase in salt concentration in the environment will let the water move inside the cell by osmosis. Hence, the contractile vacuole will not perform its function and will not be able to regulate osmoregulation.
Other options are incorrect because slight changes in the temperature or pH won't affect the contractile vacuole and it will still be able to perform its function.
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.
Answer:
D. It absorbs photons from the sun and gives energy to electrons.
Answer: molecule
Explanation: common knowledge
Hydrogen bond. Although other ones are equally as important such as a dipole-induced dipole
