Photosynthesis and Respiration Questions

Main products of the light-dependent reactions in photosynthesis

ATP, NADPH, and oxygen (O₂)

Where does the Calvin Cycle take place in the chloroplast?

The stroma

Describe the role of chlorophyll in photosynthesis

Chlorophyll absorbs light energy and converts it into chemical energy during photosynthesis

How is ATP produced in the light-dependent reactions?

By chemiosmosis

Explain the significance of photolysis in photosynthesis

Photolysis is the splitting of water molecules into oxygen, protons, and electrons using light energy. This provides electrons for the photosystems and releases oxygen as a byproduct.

What is the role of rubisco in the Calvin Cycle?

Rubisco catalyzes the carbon fixation of CO₂ to RuBP

Compare and contrast cyclic and non-cyclic photophosphorylation

Cyclic photophosphorylation involves only photosystem I and produces ATP, but not NADPH or O₂. Non-cyclic photophosphorylation involves both photosystems I and II, producing ATP, NADPH, and O₂.

Explain how different environmental factors can limit the rate of photosynthesis

Light intensity, CO₂ concentration, and temperature. If these are not optimal, the rate of photosynthesis decreases

What are the four stages of aerobic respiration, in order?

Glycolysis, the link reaction, the Krebs cycle, and oxidative phosphorylation

Where does glycolysis take place, and what are its main products?

It takes place in the cytoplasm and produces pyruvate, ATP, and NADH

Describe the role of the electron transport chain in oxidative phosphorylation

Energy from electrons pumps protons from the mitochondrial matrix to the intermembrane space, creating a steep electrochemical gradient

What is oxidative phosphorylation?

The final, major ATP-producing stage of aerobic respiration in mitochondria

How is anaerobic respiration different in plants and animals?

In animals, anaerobic respiration produces lactate, while in plants and yeast, it produces ethanol and CO₂

Why is the Krebs cycle also known as the citric acid cycle?

Citric acid is the first compound formed when acetyl-CoA enters the cycle

Explain the role of NAD and FAD in cellular respiration

They act as electron carriers, accepting electrons and hydrogen ions during glycolysis, the link reaction, and the Krebs cycle. They transfer these electrons to the electron transport chain to drive ATP production.

How do the products of respiration differ between aerobic and anaerobic conditions?

Aerobic respiration produces CO₂, water, and up to 38 ATP molecules per glucose molecule, while anaerobic respiration produces fewer ATP molecules and lactic acid in animals or ethanol and CO₂ in plants and yeast