Which is true for both photosynthesis and cellular respiration?
a. they are simple chemical reactions.
b. they are complex chemical reactions.
c. they require light energy from the sun.
d. they require cells to use water.

Both the process photosynthesis and cellular respiration require cells to use water.

Further Explanation:

Photosynthesis is the process in which green plants compose their own food in the form of carbohydrates. Photosynthesis is a two-step process that comprises of the light-dependent and dark reactions. In the light-dependent reactions, the energy is generated while in the dark reactions, the energy is used up.

The sunlight is trapped by the chlorophyll that is present in the leaves. Carbon dioxide is also obtained from the environment. The process results in the formation of starch and oxygen as a byproduct. These substances are then released by the chlorophyll. The energy in the form of ATP and NADH remains in the chloroplast and is used up in the Calvin cycle.

Cellular respiration is a chemical process by which energy is produced in the form of ATP (adenosine triphosphate). It occurs in three steps, namely; glycolysis, citric acid cycle and electron transport chain.

1. Glycolysis: in this cycle, the glucose is broken down into a smaller substance called pyruvate in the absence of oxygen. It occurs in the cytoplasm of the cell.

2. Citric acid cycle: In this, three-carbon pyruvic acid molecules produced during the glycolysis cycle are decarboxylated. The two carbon molecules from acetyl CoA enters the cycle. This reaction occurs in a closed-loop, including eight steps.

3. Electron transport chain: The electron transport chain is a sequence of proteins and other molecules present in the inner membrane of the mitochondria. The transfer of electrons occurs in a chain of the redox reaction. The energy formed during the reaction is preserved in the form of a protein gradient. This protein gradient is used in the formation of ATP by the process called chemiosmosis. The combination of ETC and chemiosmosis is called oxidative phosphorylation. Thus, both the process involves water either as a reactant or produces as a byproduct.

Learn more:

1. Learn more about carbohydrate monomer

2. Learn more about core muscle stabilization

3. Learn more about energy storage?

Answer Details:

Grade: High School

Subject: Biology

Topic: Respiration

Keywords:

Photosynthesis, cellular respiration, dark reaction, process, oxygen, water, glucose, carbon dioxide, animal, plant, light-dependent reaction, oxidized, reduced.