Unit 3: Cellular Energetics

These flashcards cover key concepts from the lecture notes on cellular energetics, including enzyme function, photosynthesis, cellular respiration, and the impact of environmental factors on enzyme activity.

What must be compatible for an enzyme-mediated chemical reaction to occur?

The shape and charge of the substrate must be compatible with the active site of the enzyme.

What is the function of enzymes in biological processes?

Enzymes are biological catalysts that facilitate chemical reactions in cells by lowering the activation energy.

What happens if a mutation causes a negatively charged amino acid in the active site?

The charge at the active site would be wrong, preventing the substrate from binding, and the enzyme would not function.

What is activation energy?

The amount of energy required for a chemical reaction to happen.

How does high temperature affect enzyme activity?

High temperature can denature enzymes, disrupting their structure and function.

What is the result of increasing the temperature beyond optimal for an enzyme?

It can lead to changes in the enzyme’s structure, decreasing its ability to catalyze reactions.

What does the term 'denaturation' refer to?

Denaturation is the disruption of protein structure, eliminating the ability to catalyze reactions.

What is the role of competitive inhibitors?

Competitive inhibitors bind to the active site of the enzyme, preventing the substrate from binding.

What processes are involved in photosynthesis?

Photosynthesis converts carbon dioxide and water into carbohydrates and oxygen using light energy.

What is the equation for cellular respiration?

6 O2 + Glucose → 6 H2O + 6 CO2.

Where does the Krebs cycle occur?

The Krebs cycle takes place in the mitochondrial matrix.

What is NADH and its role in cellular respiration?

NADH carries electrons to the electron transport chain inside the mitochondria.

What is meant by 'oxidative phosphorylation'?

The process where ATP is produced from ADP and inorganic phosphate during cellular respiration.

What happens during fermentation?

Fermentation allows glycolysis to continue in the absence of oxygen, producing organic molecules like alcohol and lactic acid.

What is the significance of the proton gradient in cellular respiration?

The proton gradient drives ATP synthesis via ATP synthase during oxidative phosphorylation.