respiration module 5

what are the 3 Co-enzymes in respiration

coA

FAD

NAD

function of coA

Accepts acetate ( 2 C) forming acetyl coA during link reaction

Acetyl coA breaks down → 2C ( kreb cycle)

what vitamins synthesis the co-enzymes

NAD → B3

FAD → B2

coA → B5

Function of FAD

helps dehydrogenases in krebs cycle

how many ATP molecules does FAD produce in oxidative phosphorylation ?

1.5 ATP

differences between NAD and NADP

NADP contains additional phosphate group on ribose sugar

definition of a coenzyme 

non protein molecule that allows a enzyme to work

what do FAD and NAD act as

hydrogen carriers to other molecules

mitochondrion structure ( Image)

adaptation of Mitochondrion

folded cristae increases SA : Vol ratio to maximise respiration 

what are the 4 stages of Aerobic respiration

1) Glycolysis

2) the Link reaction

3) Krebs cycle

4) Oxidative phosphorylation

acronym to remember stages of Respiration

Girls Lick Kids Often

where does Glycolysis occur

Cytoplasm

where does the Link reaction and krebs cycle

 matrix of Mitochondrion 

role of respiration

 makes ATP to releases energy from respiratory substrates

examples of respiratory substrates

glucose

fatty acids

amino acids

Why does glycolysis occur in cytoplasm

glucose cant cross outer mitochondrion membrane

pyruvate can

why does glycolysis happen in both anaerobic and aerobic respiration

anaerobic process → doesn’t require Oxygen

function of glycolysis

makes pyruvate from glucose

how many carbons does pyruvate contain

3 C

what type of process is Phosphorylation 

active process requires ATP 

glycolysis process

Glucose → Hexose phosphate → Hexose bisphosphate →  2x TP → 2x Pyruvate 

How to remember glycolysis intermediates 

Gross → glucose 

people → Phosphate ( Hexose)

beat  → Bisphosphate ( Hexose)

To → TP

Porn → Pyruvate 

Which stages of Glycolysis does phosphorylation happen

Glucose → hexose Phosphate → Hexose Biphosphate

what happens to TP in Glycolysis

TP gets oxidised → loses 2 H⁺ to form Pyruvate

2 H⁺ reduce 2 NADs to 2 NADH

what are the products of Glycolysis

2 ATP

2 NADH

2 pyruvate

Glycolysis how many ATPs are made and why

2 ATP

phosphorylation of Glucose to Hexose Bisphosphate → use 2 ATP

Oxidation of TP to pyruvate makes 4 ATP

2 stages of glycolysis 

active phosphorylation of Glucose to Hexose Bisphosphate  

Oxidation of TP to 2 pyruvates 

what do the products of Glycolysis go

2 NADH → Oxidative phosphorylation

2 pyruvate → actively transported to Link reaction

2 ATP → used for energy 

where does Oxidative phosphorylation occur

Inner mitochondrial membrane

function of the Link reaction

Converts Pyruvate → Acetyl coA

how many carbons does acetate contain?

2C

what happens in the Link reaction

Pyruvate is decarboxylated and Oxidised 

loses Carbon → forms CO₂

loses H⁺ → forms NADH

forms acetate which combines to CoA 

forming Acetyl CoA 

how many times does the Link reaction and krebb cycle for 1 molecules of glucose

Twice

products of Link reaction

2x Acetyl CoA → goes to krebs cycle

2 NADH

2 CO₂

what happens to all NADH and FADH formed

go to oxidative phosphorylation

what happens to CO₂ formed in Link reaction

excreted as a waste product 

which stages of Respiration produce CO₂

Link reaction

Krebs cycle

stages of Krebb cycle

Formation of Citrate

Formation of 5 carbon compound

Regeneration of oxaloacetate

Krebb cycle formation of citrate

acetate (2C) combines with oxaloacetate (4C)→ citrate ( 6C)

CoA leaves back to link reaction

Krebb cycle Formation of 5 carbon compound

citrate ( 6C) is decarboxylated and dehydrogenated → 5 carbon compound

produces CO₂

H⁺ forms NADH

Krebb cycle Regeneration of Oxaloacetate 

5 carbon compound converted to Oxaloacetate

decarboxylation → loses CO₂

dehydrogenation → 2 NADH and 1 FADH

ATP is formed ( substrate level phosphorylation)

when does substrate level phosphorylation happen in respiration

Krebs cycle 

how many times does the krebs cycle turn for 1 glucose molecule

twice

products of 1 turn of krebs cycle

1 coA

Oxaloacetate

2 CO₂

1 ATP

3 NADH

FADH

Oxidative phosphorylation process

NADH and FADH are oxidised → H₂ → 2H⁺ + 2e⁻

e⁻ move along electron transport chain → releases energy for electron carriers to pump protons from matrix to intermembrane space 

creates a proton electrochemical gradient 

protons move back into mitochondrial matrix through ATP synthase causes

ATP synthase to convert ADP + Pi → ATP 

( process is chemiosmosis)

at end of chain protons electrons and O₂ combine to form water ( 2 H₂O)

Role of O₂ in respiration

what is the final electron acceptor in Oxidative phosphorylation

Krebbs cycle image

Link reaction image

Glycoly sis Reaction Image

how many ATP molecules are made for each 1 molecule of glucose 

28 ATP

why does substrate level phosphorylation happen in Krebb cycle

Phosphate group combines with ADP from intermediate

Oxidative phosphorylation image

2 quantitative changes in intermembrane space as a result of oxidative phosphorylation

PH decreases → more acidic 

increase in Positive charge → higher H⁺ conc 

why does aerobic respiration yield fewer molecules than theoretical maximum

ATP is used in the shuttle mechanism transport NADH into membrane

proton leakage from matrix to intermembrane 

Structural features of mitochondria that show its evolved from bacteria

Double membrane

Mitochondria has DNA and ribosomes

what stage of respiration happens in anaerobic and aerobic respiration

Glycolysis

what are the two types of Anaerobic respiration

Alcoholic fermentation

Lactate fermentation

similarities between Alcoholic and lactate fermentation

Both occur in cytoplasm

both produce 2 ATP

glycolysis occurs in both

differences between Alcoholic and lactate fermentation

Alcoholic → occurs in yeast cells, produces ethanol, produces CO₂ 

Lactate → Occurs in mammals, produces lactate and produces ethanal intermediate

what happens to excess lactate in body

Converted into glucose by gluconeogenesis in liver 

Why can glycolysis occur without O₂

Glycolysis requires NAD

Production of lactate regenerates NAD

How is lactate formed in Lactate fermentation

NADH ( from glycolysis) reduces pyruvate → forms lactate and NAD.

Advantages of Glycolysis being anaerobic

small amounts of ATP can be produced keeping biological processes (Muscle contractions ) going

Lactate fermentation ( Image)

Advantages of Anaerobic respiration

provides a Survival Advantage in low O₂ environments

Produces ATP quickly

allows for muscle contractions ( No O₂)

Regenerates NAD so glycolysis can continue

How is ethanol formed in Alcoholic fermentation 

Pyruvate loses CO₂ → forms ethanal → NADH reduces ethanal → Ethanol + NAD ( reused in glycolysis)

Alcoholic fermentation ( Image)

Why does Anaerobic respiration have a lower ATP yield then Aerobic

Anaerobic respiration → only glycolysis occurs ( produces 2 atp)

No krebs cycle and Oxidative phosphorylation → require O₂

Why does NADH produce more ATP then FADH

NADH → Electrons flow through more electron carriers then FADH

why is lactate ( lactate acid) toxic?

Denature enzymes and proteins → muscle fatigue

decrease cell pH

Why is lactate fermentation unsustainable ?

ATP is used to convert Lactate into Glucose 

net loss of ATP

What are respiratory substrates 

Biological molecules that can be broken down in respiration to release energy

How can triglycerides ( Lipids) be used as Respiratory substrates

Broken down into glycerol + 3 fatty acids

glycerol → pyruvate enters krebb cycle

fatty acids undergo beta oxidation → acetyl CoA → generates many ATP

Disadvantages of using proteins as respiratory substrate

less proteins for enzymes → less enzymes

deamination uses ATP - decreases net ATP production

what are the respiratory substrates

Carbohydrates

proteins

Lipids

where do proteins and lipids enter respiration

In krebs cycle

what is the RQ of the respiratory substrates

Carbohydrates → 1

Lipids → 0.7

Proteins → 0.8 - 0.9

How can proteins be used as Respiratory substrates

broken down into amino acids ( deamination) → Pyruvate

(Respiratory substrate ) Hydrogen atom amount and ATP production relationship

Higher the Hydrogen atoms per unit mass = More NADH and FADH → more ATP generated

Respiratory quotient equation

(Molecules of CO₂ released / Molecules of O₂ consumed)

Uses of a respiratory quotient

Tell us type of respiratory substrate used

type of respiration ( anaerobic or aerobic)

what does a RQ of 1 or below show

Aerobic respiration

What does a RQ of 1 or above show

Respiring anaerobically and aerobically

why do plants have Low RQ 

CO₂ released in respiration is being used in photosynthesis 

Similarities between Yeast and mammal respiration

Both use glucose

NADH gets oxidised

Why do lipids have the highest energy value released

Most hydrogen atoms per unit mass of respiratory substrate ( named)

what does Beta Oxidation produce

FADH

NADH

What does Q10 mean / show

every 10°C increase the rate x2

what does a negative distance on respirometer mean

liquid/ meniscus moves backwards/downwards

RQ value and C-H bond ratio

Lower the C-H bonds = the higher the RQ value

( less energy required to break bonds)