Cellular Respiration and Fermentation

What type of respiration requires energy?

What type of respiration requires energy?

Aerobic

What type of respiration does not require energy?

Anaerobic

How much ATP does aerobic respiration make?

36

How much ATP does anaerobic respiration make?

2

What is the equation for cellular respiration?

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

What type of reaction is cellular respiration?

Exergonic, spontaneous, -∆G

What is the ∆G for cellular respiration?

-686 kcal/mol

Is oxidation exergonic or endergonic?

Exergonic

What are the steps of cellular respiration?

1. Glycolysis

2. Krebs Cycle/Citric Acid Cycle

3. Oxidative Phosphorylation

Where does glycolysis occur?

Cytoplasm/Cytosol

What are redox reactions?

oxidation-reduction reaction

Oxidation vs. Reduction

OIL RIG

• Oxidation is loosing (electrons)

• Reducing is gaining (electrons)

Is the conversion of NAD₊ to NADH oxidation or reduction?

• How does this happen?

Reduction

• Two hydrogens are added. The first is added to the molecule and the second is stripped of its electrons leaving a H⁺, or a proton.

What is the basic idea of what happens in gycolysis?

A 6-carbon glucose is broken into 2 3-carbon pyruvic acids through the use of 2 ATP as start-up energy

Describe the reactions and molecules involved in glycolysis.

• Glucose is phosphorylated twice and creates 2 molecules of G3P/PGAL

• NAD₊ is reduced to NADH (Hydrogens are oxidized)

• 4 ATP is produced through 2 steps of substrate-level phosphorylation

• The final molecule is pyruvate/pyruvic acid

What is substrate-level phosphorylation?

The phosphate is not free-floating, but donated from another molecule

What are the end products of glycolysis?

• 2 ATP (Makes 4, needs 2 to start = 4-2 = 2)

• 2 NADH

What happens in-between glycolysis and the citric acid cycle?

• What does this process also make?

The 2 pyruvic acids are transformed into 2 Acetyl CoA (with coenzyme A)

• It also makes 2 NADH and 2 CO₂

Where does the Kreb’s Cycle take place?

Mitochondrial Matrix

Describe the reactions and molecules involved in the citric acid cycle/krebs cycle.

• What does it make?

• 3-carbon Acetyl CoA combines with 4-carbon Oxaloacetate to make 6-carbon Citric Acid (7th carbon becomes CO₂)

• After many redox reactions and the creation of CO₂ as well as the usage of GDP → GTP conversion

  • Makes 3 NADH, 1 FADH₂, 1 ATP

    • x2 for both molecules

Where does oxidative phosphorylation occur?

Inner membrane of mitochondria

What are the parts of oxidative phosphorylation?

1. Electron Transport Chain (ETC)

2. Chemiosmosis

Describe the reactions and molecules involved in the electron transport chain.

• Electrons are passed down the chain, the energy level of each subsequent protein being lower that the last

• Each protein complex is reduced and the oxidized as it passed electrons

  • When the protein receieves an electron, its shape changes and an H⁺ (proton) is given off

Describe the reactions and molecules involved in chemiosmosis.

• ATP synthase(protein complex), produces ATP from ADP and inorganic phosphate

• For this, there must be a shape change in the ATP, which is achieved using the H⁺ from ETC, which flows through the synthase and back into the matrix

  • Makes chemiosmosis an energy-coupling mechanism

What is a protein motive force?

The force that spins the synthase protein

How much ATP is made in chemiosmosis?

34

Is ATP created as a direct result of ETC?

Nope, it’s a direct result from chemiosmosis

Do plants and bacteria do aerobic respiration?

Yup

How do bacteria achieve aerobic respiration?

They use their cell membranes to house the ETC proteins

Is the electrical gradient of ETC more positive or negative?

Positive