Question

What is the name of a cycle which generates energy and splits water into hydrogen and Oxygen?
A. Glycolysis
B. Photophosphorylation
C. Citric acid cycle
D. Electron transport cycle

Answer 1

Hint: During photosynthesis, light energy transfers electrons from water to carbon dioxide to produce carbohydrates. In this process, the carbon dioxide is “reduced,” or receives electrons, and the water becomes “oxidized,” or loses electrons. Ultimately, oxygen is produced along with carbohydrate

Complete Answer:
Let us analyse the options to find the correct answer.

Option A: Glycolysis is the process in which one molecule of glucose is converted into two molecules of pyruvate, two hydrogen ions and two molecules of water. Through this process, the 'high energy' molecules of ATP and NADH are synthesised. The pyruvate molecules then proceed to the link reaction, where acetyl-coA is produced.

Option B: Photophosphorylation is the process of utilizing sunlight energy from photosynthesis to convert ADP to ATP. During the process water molecules are split into hydrogen and oxygen.

Option C: Tricarboxylic acid (TCA) cycle, also known as the Krebs or citric acid cycle, is the main source of energy for cells. The cycle uses chemical energy of acetyl coenzyme A (acetyl CoA) into the reducing power of NADH. It is an important part of aerobic respiration.

Option D: Electron transport chain is a series of complexes that transfer electrons from electron donors to electron acceptors via redox reactions. It couples this electron transfer with the transfer of protons across a membrane. The electron transport chain is built up of peptides, enzymes, and other molecules.

Hence the correct answer is option B.

Note: There are two types of photophosphorylation cycles - Cyclic and non cyclic. The importance of cyclic photophosphorylation is that it can synthesize ATP at low cost and only photosystem I is active in it.