Bioenergetics (Chapters 5 & 6)

This set of flashcards covers key concepts in bioenergetics, including cellular respiration, photosynthesis, and fermentation.

What is the main purpose of cellular respiration?

To generate ATP through chemical reactions involving glucose and oxygen.

What is the equation for cellular respiration?

C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP.

What differentiates an aerobe from an anaerobe?

Aerobes require oxygen for growth, while anaerobes grow only in the absence of oxygen.

What is a facultative anaerobe?

An organism that can perform aerobic respiration but can switch to fermentation when oxygen is unavailable.

Define cellular respiration.

A series of redox reactions where cells generate ATP by transferring electrons from glucose to an electron acceptor.

What occurs during aerobic respiration?

Oxygen is the final electron acceptor in the process of ATP production.

What is glycolysis?

The breakdown of glucose into two pyruvate molecules, producing 2 ATP and 2 NADH.

Where does glycolysis occur?

In the cytoplasmic fluid of the cell.

What are the two major phases of glycolysis?

The energy investment phase and the energy liberation phase.

What is produced during the Krebs cycle?

2 ATP, 6 NADH, and 2 FADH2 per glucose molecule.

What role does the electron transport chain play in cellular respiration?

It transfers electrons through carriers to create a proton gradient for ATP synthesis.

What is chemiosmosis?

The process of ATP production that occurs due to the flow of protons down their concentration gradient through ATP synthase.

What is oxidative phosphorylation?

The production of ATP using the energy from a proton gradient to phosphorylate ADP.

What is fermentation?

An ATP-generating process that occurs in the absence of oxygen, allowing glycolysis to continue.

How does lactic acid fermentation function?

NADH donates electrons to pyruvate, regenerating NAD+ and producing lactic acid.

What is the maximum yield of ATP from one glucose molecule during aerobic respiration?

36 to 38 ATP.

What food molecules can be utilized for energy besides glucose?

Proteins, fats, and other organic molecules.

What happens to the byproducts of aerobic respiration?

CO2 is released as a waste product, and water is formed.

What is pyruvate grooming?

The process in which pyruvate is converted into acetyl CoA before entering the Krebs cycle, involving decarboxylation and the reduction of NAD+ to NADH.

Where does pyruvate grooming happen?

In the mitochondria of eukaryotic cells.

What is the 4 carbon molecule called that accepts 2- carbon acetyl CoA group in Krebs cycle?

Oxaloacetate

What is the 1st product in the citric acid cycle?

Citric acid

Where do electrons travel in ETC?

Through a series of protein complexes and electron carriers, ultimately reaching oxygen.

What makes H+ gradient? Where does the H+ gradient take place?

As electrons move down ETC- release energy (high to low energy) energy is used to pump H+ protons from matrix to inter membrane space

What are the primary electron donors?

NADH and FADH2

What is the final electron acceptor?

Oxygen, which combines with electrons and protons to form water.