Question

Active transport of ions by a cell requires
A) High temperature
B) Low temperature
C) Alkaline pH
D) ATP

Answer 1

Hint:Active transport can be defined as the process by which molecules are transported from a region or lower concentration to higher concentration against a gradient utilising some energy.

Complete answer:
Let us analyse the options and find out the correct answer.

Option A: Even though the temperature is increased, there is no effect of it on the transport of molecules against the concentration gradient. Therefore, this is the incorrect option.
Option B: Low temperature has no effect on active transport as it does not help in transporting the molecules against the gradient. Therefore, this is the incorrect option.
Option C: Alkaline pH means a pH level between 7.35 to 7.45. But it is to be taken in consideration that, alkaline pH does no good for transportation of molecules against the concentration gradient. Therefore, this is the incorrect option.
Option D: As the molecules are being transported against the concentration gradient, i.e. from a lower gradient to a higher gradient, energy is required to transport. The energy is utilized as ATP as it is the energy currency of a cell. Therefore, this is the correct option.
During the process of active transport, a protein pump is used by the cell which uses ATP to move molecules.

Thus, the correct option is (D) ATP.

Note: Examples of active transport in the cell are,
Movement of calcium ions out of the cardiac muscles.
Uptake of glucose molecules by the cell is done using a Na - K pump which utilises ATP to transport glucose from outside the cell to inside the cell.