Chapter 7 - Cellular Respiration & Fermentation

These flashcards cover key terms and concepts related to cellular respiration and fermentation from the lecture notes.

Redox Reactions

Reactions that involve the transfer of electrons between reactants, releasing energy that synthesizes ATP.

Oxidation

The process of losing electrons (the substance is oxidized).

Reduction

The process of gaining electrons (the substance is reduced).

Glycolysis

The splitting of glucose into two molecules of pyruvate, occurring in the cytoplasm, and does not require oxygen.

very little ATP formed by substrate level phosphorylation

pyruvate oxidation (pre-citric acid)

The conversion of pyruvate to acetyl-CoA, producing 2 NADH and 2 CO2, occurring in the mitochondria.

requires oxygen

1. 2 CO2 released

2. 2 NADH produced (e- released from NAD+)

3. results in 2 Acetyl CoA (highly reactive)

Citric Acid Cycle (Kreb’s Cycle)

A series of reactions in the mitochondria that completes the breakdown of glucose, producing 2ATP, 2NADH, and 2FADH2.

Substrate Level Phosphorylation

The process of forming ATP by directly transferring a phosphate group from an organic molecule to ADP.

Oxidative Phosphorylation

The process that generates ATP through the electron transport chain and chemiosmosis; creates 90% of ATP.

electron transport chain

A series of protein complexes that transfer electrons from electron donors (NADH and FADH2) to electron acceptors, ultimately producing ATP.

in cristrae

no ATP generated

O2 pulls e- down the chain

what happens to NAD and FAD in electron transport chain

reused in cellular respiration

electrochemical gradient

the energy in the electron transport chain is used for sending H+ from matrix into intermembrane space

Complex 1

NADH transfers e- directly (high energy level)

spans the entire membrane

Complex 2

FADH2 (lower energy level) transfers e-

doesn’t pump protons across, less energy needed

contributes less to gradient

Ubiquinone (Q)

mobile e- carrier…….. brings to complex 3

Complex 3

H+ pumped across membrane and to cyt C

Cytochrome C (cyt c)

carries e- to complex 4

complex 4

final H+ pumped and passes e- to O2

water is created

NAD+

An electron carrier involved in cellular respiration that is reduced to NADH.

FAD

An electron carrier that gets reduced to FADH2 during the citric acid cycle.

Chemiosmosis

The movement of ions (hydrogen ions) across a selectively permeable membrane down their electrochemical gradient, which generates ATP.

proton motive force

ATP synthase is used for

moving H+ across membrane generating ATP (adds phosphate to ADP)

hydrophilic tunnel bc protons are hydrophobic

NADH and FADH2 produce how much ATP?

NADH = 2.5 ATP

FADH2 = 1.5 ATP

ATP produced

1. 8 NADH = 20 ATP, 2FADH2 = 3ATP

1. big or little bus

   2 NADH or 2 FADH2 = 5 or 3 ATP

2. 28 or 26 ATP created