C1.2 Cell Respiration

What monomer is ATP?

nucleotide

What is the structure of an ATP molecule?

adenine base, five-carbon ribose sugar, three phosphate groups

What does ATP stand for?

Adenosine Triphosphate

How does energy release?

Breaking bonds between phosphates

What does ADP stand for?

Adenosine Diphosphate

Traits of ATP

1. soluble in water → can be in the cytoplasm

2. can be regenerated

3. cannot cross membranes → compartmentalized where it is needed

Functions of ATP

1. synthesize macromolecules → anabolic, endothermic reactions

2. active transport → moving against concentration gradient, protein pumps

3. movement → movement of all cell components, locomotion

How does the third phosphate break off ATP?

hydrolysis

Respiration

biochemical process that releases energy from carbon compounds to produce ATP

Gas exchange

the process of oxygen and carbon dioxide diffusing into and out of cells

Ventilation

breathing

Aerobic

with oxygen

Anaerobic

without oxygen

Differences between aerobic and anaerobic

Aerobic

• with oxygen

• mitochondria

• can utilize many more macromolecules as initial source

• produces H2O and CO2

• 30 ATP

Anaerobic

• cytoplasm

• without oxygen

• only use carbohydrates as initial energy source

• produce lactate in humans

• produce ethanol in yeast

• 2 ATP

Why do we do anaerobic?

necessary when you need ATP but don’t have enough O2, and because the NAD→NADH repeats the cycle

Oxygen debt

the amount of oxygen you must absorb following anaerobic respiration in order to break down the lactate

Aerobic respiration equation

glucose + O2 → CO2 + H2O + ATP + heat

Respirometer

measures oxygen consumption

Electron carriers

substances that are easily oxidized and reduced

What is NAD?

a molecule that carries electrons

reduction

gain of electron

oxidiation

loss of electrons

Four main steps of aerobic respiration

1. Glycolysis

2. Link rxn

3. Krebs cycle

4. Electron transport chain

Explain the process of glycolysis

• occurs in the cytoplasm

• anaerobic

• produces: net 2 ATP, 2 pyruvate, 2 NADH

where does glycolysis occur?

cytoplasm

explain each step of glycolysis

1. 6-carbon glucose molecule

2. 2 phosphate from 2 ATP attach to carbons (phosphorylation) which makes the glucose unstable

3. glucose splits in half (lysis)

4. NAD picks up H electron and becomes NADH (oxidation)

5. floating phosphates attach to other side of the 3-carbon chains

6. 2 ADP take the two phosphate and become 2 ATP (ATP formation)

7. pyruvate is made

describe the differences between the aerobic and anaerobic cell respiration

glucose → glycolysis → pyruvate

pyruvate (cytoplasm) → no oxygen → anaerobic → CO2 + no more ATP (2 total) + ethanol + lactic acid

pyruvate (mitochondria) → oxygen → aerobic → CO2 + lots of ATP + H20

Label all the parts of the mitochondria

matrix, intermembrane space, inner membrane, outer membrane

where does the lnk rxn occur?

matrix

where does the krebs cycle occur?

matrix

where does the electron transport chain occur?

inner membrane

what is the end product of the link rxn?

acetyl coA

decarboxylation

removal of carboxyl group

explain the process of the link rxn

1. pyruvate gets oxidized/NAD gets reduced and becomes NADH (pyruvate has 4 H’s left)

2. removes a carboxyl group (decarboxylation)

3. 2 carboxyl groups = acetyl

4. acetyl enters the matrix and bonds with coenzymeA creating acetylcoA

happens twice, for each pyruvate

explain the Krebs cycle

1. acetyl coA will bond with oxaloacetate (4 carbon molecule) to create citrate and coA leaves

2. NAD → NADH (reduction) and removes an original CO2

3. NAD → NADH (reduction) and removes an original CO2 (no more original CO2)

4. ADP and floating phosphate create ATP

5. FAD → FADH2

6. NAD → NADH creates oxaloacetate

7. cycle repeats again for second pyruvate

what are the products of the Krebs cycle?

• 3 NADH x2

• 2 CO2 ×2

• FADH2 ×2

• ATP x2

From glycolysis to the Krebs cycle, what are the products?

• 12 NADH

• loses original 6 CO2

how many H is made in each process?

2 NADH → glycolysis

2 NADH → link rxn

6 NADH → Krebs cycle

2 FADH2 → Krebs cycle

oxidative phosphorylation

use of oxygen as the final electron acceptor in the production of ATP

Chemiosmosis

movement of H+ from high to low across membrane