Cellular Respiration and Energy Production

Flashcards covering glycolysis, acetyl-CoA formation, Krebs cycle, electron transport chain, shuttles, anaerobic fermentation, ATP yield, and glycogen storage.

Where does glycolysis occur in the cell?

Cytoplasm (cytosol).

What are the net products of glycolysis per glucose molecule?

2 pyruvate, 2 NADH, and 2 ATP (net).

What are the three types of phosphorylation mentioned in energy metabolism?

Substrate-level phosphorylation, Oxidative phosphorylation, and Photophosphorylation.

Which carriers deliver electrons to the mitochondrial electron transport chain after glycolysis?

NADH and FADH2.

What is produced from pyruvate to enter the Krebs cycle, and what is released in this step?

Pyruvate is converted to Acetyl-CoA with release of CO2 and production of NADH.

Where does the Krebs cycle occur?

Mitochondrial matrix.

For each acetyl-CoA entering the Krebs cycle, what are the outputs?

2 CO2, 3 NADH, 1 FADH2, and 1 ATP (substrate-level).

What are the total outputs of the Krebs cycle per glucose molecule?

6 NADH, 2 FADH2, 2 ATP, and 4 CO2.

Where do NADH and FADH2 donate electrons, and what is the final electron acceptor?

Electron transport chain; final acceptor is O2 (forming water).

Name the two anaerobic pathways described and their end products.

Alcohol fermentation (produces CO2 and ethanol) and lactic acid fermentation (produces lactate).

What are the net products of alcoholic fermentation from glucose metabolism?

Net 2 ATP, 2 CO2, and 2 ethanol.

What are the net products of lactic acid fermentation from glucose metabolism?

Net 2 ATP and 2 lactate.

Name the two mitochondrial shuttles that transfer cytosolic NADH into mitochondria and their ATP yields.

Glycerol-3-phosphate shuttle (yields about 4 ATP from 2 NADH); Malate-Aspartate shuttle (yields about 6 ATP from 2 NADH).

What is the total ATP yield from aerobic respiration for most body cells, and what about liver, kidney, and heart?

About 36 ATP in most cells; about 38 ATP in liver, kidney, and heart.

Where is glycogen stored in the body according to the notes?

Liver and skeletal muscle.

During glycolysis, how many carbons are in glucose and in the resulting pyruvate molecules?

Glucose has 6 carbons; it becomes two pyruvate molecules (2 × 3 carbons).

What are the products of pyruvate conversion to Acetyl-CoA per glucose?

2 Acetyl-CoA, 2 CO2, and 2 NADH.

How does acetyl-CoA begin the Krebs cycle with oxaloacetate?

Oxaloacetic acid (4C) combines with acetyl-CoA (2C) to form citrate (6C).