If a type of transport uses metabolic energy then which of t

If a type of transport uses metabolic energy, then which of the following statements also applies to that type of transport? Please select (a), (b), (c), (d), or (e).

(a) Substances are moved against the concentration gradient.

(b) Substances are not moved via a transport protein.

(c) An equilibrium will be established.

(d) Diffusion will occur.

(e) Substances are moved from high concentration to low concentration.

Solution

the answer is (a) substance are moved against the concentration gradient.

explanation: these type of transport is known as the active transport.

as compared to passive transport, in which the molecules move along the concentration gradient that is from ts region of its higher concentration to the region of its lower concentration and no energy input is required in this process and is driven by simple thermal energy.

in active transport the molecule moves against the concentration gradient i.e. from lower to higher concentration and the process is done against the normal flow it requires metabolic energy i.e. the energy from the respiration which is achieved by the hydrolysis of ATP. these is achieved by certain protein carriers that bind the molecule on its lower concentration side , energy obtained by the respiration then changes the shape of the carrier thus it releases the molecule on the other side of higher concentration gradient.

eg: these type of active transport occurs in the villi of animals during digestion when maximum food is absorbed by the villi the concentration of food molecule inside the villi increases to a amount that no more food molecule can diffuse in at this point of time. since more food molecule are still required the food molecules are transport against the concentration gradient by active transport by utilizing energy.