Uptake of glucose in the intestines in humans can take place when ___:

Answer: [D] In all the above conditions

This question is based upon active transport process in which the movement of a substance against its concentration gradient (from low to high concentration). In all cells, this is usually concerned with accumulating high concentrations of molecules that the cell needs, such as ions, glucose and amino acids. If the process uses chemical energy, such as from adenosine triphosphate (ATP), it is termed primary active transport.

Secondary active transport involves the use of an electrochemical gradient. Active transport uses energy, unlike passive transport, which does not use any type of energy. Active transport is a good example of a process for which cells require energy. Examples of active transport include the uptake of glucose in the intestines in humans and the uptake of mineral ions into root hair cells of plants. Please note that glucose uptake can take place in any of the conditions mentioned in three statements. Method of glucose uptake differs throughout tissues depending on two factors; the metabolic needs of the tissue and availability of glucose. The two ways in which glucose uptake can take place are facilitated diffusion (a passive process) and secondary active transport (an active process which indirectly requires the hydrolysis of ATP).

This question is a part of GKToday's Integrated IAS General Studies Module