BIOFOUND 3.4 Cellular Respiration pt 2

mitochondrion inner membrane

inside the outer membrane and has folds called cristae.

mitochondrion outer membrane

surrounds the entire organelle

mitochondrion intermembrane space

he area between the inner and outer membranes of the mitochondrion

mitochondrion cristae

located on the inner membrane of the mitochondrion, forming folds.

mitochondrion matrix

the space inside the inner membrane of the mitochondrion

inside the cytoplasm

where does glycolysis take place in the cell?

inside the mitochondrion

where does pyruvate processing take place in the cell?

inside the mitochondrion matrix

where does the citric acid cycle take place in the cell?

inside the inner membrane

where does electron transport and oxidative phosphorylation take place in the cell?

pyruvate is converted into acetyl-CoA, releasing CO2 and producing NADH.

what happens during pyruvate processing?

PDH (pyruvate dehydrogenase)

an enzyme complex that converts pyruvate into acetyl-CoA during pyruvate processing, producing NADH and releasing CO2 in the process.

pyruvate dehydrogenase kinase

an enzyme that inhibits pyruvate dehydrogenase by adding a phosphate group, reducing the conversion of pyruvate to acetyl-CoA.

by adding a phosphate group to it, which turns PDH off and stops the conversion of pyruvate to acetyl-CoA

how does kinase regulate the activity of PDH?

acetyl-CoA is broken down, releasing CO2, and producing energy-rich molecules like NADH, FADH2, and ATP

what happens during the citric acid cycle?

by inhibiting enzymes in the cycle when energy is high, preventing overproduction of energy and maintaining balance

how and why does NADH regulate the citric acid cycle?

when energy levels are high, slowing down the citric acid cycle to prevent excessive production of energy.

how and why does NADH regulate the enzyme irocitrate dehydrogenase?

the net effect of glucose breakdown in glycolysis

is the production of 2 ATP, 2 NADH, and 2 pyruvate molecules from 1 glucose molecule.

the net effect of glucose breakdown in pyruvate processing

the production of 2 acetyl-CoA, 2 NADH, and 2 CO2 molecules from 2 pyruvate molecules.

the net effect of glucose breakdown in the citric acid cycle

the production of 6 NADH, 2 FADH2, 2 ATP (or GTP), and 4 CO2 molecules from 2 acetyl-CoA molecules.

NADH donates electrons, which are passed through proteins, and in the process, NADH is converted back to NAD+, ready to be used again in glycolysis and other reactions.

how is the electron transport chain used to cycle NADH back to NAD+?

NADH is used to convert pyruvate into lactate (in lactic acid fermentation) or ethanol and CO2 (in alcoholic fermentation), regenerating NAD+ for use in glycolysis

how is fermentation used to cycle NADH back to NAD+?

electrons are passed through proteins, releasing energy to pump protons across the membrane, creating a gradient that helps produce ATP. This process occurs in the inner mitochondrial membrane.

what happens in the electron transport chain and where does it occur?

proton gradient

the difference in proton (H+) concentration across a membrane, which stores energy used to make ATP

when protons (H+) are pumped across a membrane by proteins in the electron transport chain, creating a higher concentration of protons on one side.

how is a proton gradient generated?

across the inner mitochondrial membrane

where is the proton gradient generated?

by allowing protons to flow back across the membrane through an enzyme called ATP synthase, which uses the energy to produce ATP.

how is the proton gradient used to make ATP?

oxidative phosphorylation

the process where energy from electrons is used to create a proton gradient, which drives ATP production in the mitochondria

ATP synthase

an enzyme that uses the flow of protons to produce ATP, the cell's energy currency.

it requires oxygen to function; without oxygen, the process can't occur efficiently

what is the major limitation of oxidative phosphorylation?

when oxygen is scarce, and pyruvate is converted into lactate, regenerating NAD+ so glycolysis can continue to produce ATP.

how does fermentation occur in human cells?