Cellular Respiration & Energy Production: Mitochondria, Glycolysis, and Electron Transport Chain

A runner is jogging and their cells are producing energy using oxygen inside the mitochondria. Where is most of this energy production happening?

Mitochondria

During exercise, your body needs energy for muscle contraction. What is ATP mainly used for in this situation?

Metabolic reactions

A scientist studies how cells break down glucose using oxygen. Which equation represents this process?

C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP)

In a lab experiment, a molecule loses electrons during a reaction. What process is this called?

Oxidation

A molecule gains electrons during a chemical reaction. What is this called?

Reduction

A student compares energy levels of molecules. Which one stores the most energy?

Glucose

A biology class is studying energy production. Which stage produces the MOST ATP (about 36-38 total overall)?

Electron Transport Chain

During cellular respiration, NAD⁺ picks up electrons. What does it become?

NADH

A student writes the reaction: NAD⁺ + electrons + H⁺ → NADH. What type of molecule is NAD⁺?

Coenzyme

Where does glycolysis occur in a cell?

Cytoplasm

A cell is functioning without oxygen. Which process can still occur?

Glycolysis

A student observes that a process does not require oxygen. What type of process is glycolysis?

Anaerobic

After glycolysis, what molecule is produced?

Pyruvate

During glycolysis, energy is used first before more is made. What are the two stages called?

Investment & harvesting

A student tracks ATP use during glycolysis. How many ATP are used in the beginning?

2

At the end of glycolysis, how much ATP is gained overall?

2 ATP

Where do the Krebs cycle and prep step occur?

Mitochondrial matrix

Where does the Electron Transport Chain take place?

Inner mitochondrial membrane (cristae)

A student lists glycolysis inputs. Which is correct?

2 ATP, 2 NAD⁺, glucose → pyruvate

During the Krebs cycle, what is produced in one turn?

1 ATP, 3 NADH, 1 FADH2

A cell is preparing pyruvate for the Krebs cycle. What does pyruvate become?

Acetyl-CoA

A student studies how ATP is made. ADP combines with what to form ATP?

Phosphate (P)

Hydrogen ions build up and move through a protein to make ATP. What is this process called?

Chemiosmosis

A person is sprinting and not getting enough oxygen. What process will their muscles use?

Fermentation

A marathon runner has plenty of oxygen. Which system are their cells mainly using?

ETC (aerobic respiration)

What makes fermentation different from aerobic respiration?

Does not require oxygen and makes less ATP

If NADH is not dropped off in the ETC, what happens?

NADH builds up

If the mitochondria is damaged, what happens to glycolysis?

Continues normally

Why is the inner mitochondrial membrane important?

Holds ETC proteins

If a cell has no mitochondria, what process can still produce ATP?

Glycolysis