Metabolism Part II

donor; acceptor

Redox reactions involve the transfer of electrons from an electron _______ to an electron ______.

Donor

Donor or Acceptor?

stores less energy

acceptor

Donor or Acceptor?

stores more energy

E₀ (Standard Redox Potential)

a measure of how easily a chemical species can be reduced (gain electrons) under standard conditions.

negative

The more ______ the E₀ → the easier for electrons to be donated.

positive

The more _____ the E₀ → the better the electron acceptor.

negative

The grater the difference between E₀ of the donor and E₀ of the acceptor, the more ______ the delta G^o’.

Electron transport

used to build up H⁺ on one side

Electron transport system

Energy released from movement of H+ along gradient is used to synthesize ATP (when H+ is transported via the membrane-bound enzyme)

ATP Synthase

H+ is transported via the membrane-bound enzyme

anaerobic

acceptors can be SO₄^2-, NO₃^-, CO₂ in which respiration?

increases

Redox potential _____ along the mitochondrial electron-transport chain

Aerobic respiration

the final electron acceptor is O₂

anaerobic respiration

acceptors can be NO₃^-, SO₄^2-, CO₂

fermentation

If no oxygen is available or cells do not have ETC, they can obtain energy through the process called what?

Fermentation

What is not an efficient process and results in the formation of far fewer ATP molecules?

respiration

What produces more ATP molecules?

Fermentation or respiration (aerobic / anaerobic)

Fermentation

•Allow the release of energy from sugar

•Does not require oxygen

•Does not require TCA cycle

•Use organic molecules as electron acceptors

pyruvic acid

formed during Glycolysis

• each gains a hydrogen from NADH

NDA

Goal of fermentation:

reoxidize NADH to _____+

Fermentation

the process of breaking down sugars without using oxygen to generate energy

8

Theoretical Maximum Yield of ATP molecules of:

Glycolysis

24

Theoretical Maximum Yield of ATP molecules of:

Krebs cycle

Homolactic fermentation

ONLY lactic acid is formed

Heterolactic fermentation

other products other than lactic acid are formed

Aerobic respiration

Which of the following types of metabolism produces more ATP?

• Aerobic respiration

• Anaerobic respiration

• Fermentation