3.4.4 - Respiration

Question 1

Hydrolysis definition

Answer 1

The addition of water to break down molecules

Question 2

Reduction definition

Answer 2

The removal of oxygen from a molecule OR the addition of hydrogen/ electrons to a molecule

Question 3

Oxidation definition

Answer 3

The addition of oxygen to a molecule OR removal of hydrogen/ elections to a molecule

Question 4

Redox reaction definition

Answer 4

A chemical reaction that involves simultaneous oxidation and reduction

Question 5

Phosphorylation definition

Answer 5

The addition of a phosphate group to a molecule

Question 6

Coenzyme definition

Answer 6

A non-protein, organic molecule, essential for normal functioning of an enzyme

Question 7

Activation energy definition

Answer 7

The energy needed to start a reaction, enzymes lower this

Question 8

Differences between aerobic/ anaerobic respiration

Answer 8

Aerobic = requires oxygen, produces more ATP than anaerobic
Anaerobic = doesn't require oxygen, produces less ATP and doesn't need a mitochondria

Question 9

Why does the cell store energy at ATP?

Answer 9

ATP can be easily hydrolysed to release energy, cannot pass out of the cell and stores/ releases energy in small amounts

Question 10

Where does glycolysis occur?

Answer 10

In the cytoplasm of all living cells

Question 11

Chemicals needed for glycolysis?

Answer 11

Glucose
2 NAD
2 ATP

Question 12

Chemicals produced in glycolysis?

Answer 12

2 pyruvate
4 ATP
2 NADH

Question 13

Respiration definition

Answer 13

Controlled release of energy/ ATP from organic molecules

Question 14

4 stages of aerobic respiration?

Answer 14

1. Glycolysis
2. Link reaction
3. Kerbs cycle
4. Electron transport chain

Question 15

Respiration word equation?

Answer 15

Glucose + oxygen –> carbon dioxide + water (+38ATP)

Question 16

Products of anaerobic respiration?

Answer 16

For plants: Ethanol + CO2 + NAD

For animals: Lactate + NAD

Question 17

Link reaction equation?

Answer 17

Pyruvate + NAD + CoA –> AcetylCoA + NADH + CO2

Question 18

Where does the link reaction occur?

Answer 18

The matrix of the mitochondria

Question 19

Where does the Krebs cycle occur?

Answer 19

The matrix of the mitochondria

Question 20

Krebs cycle process?

Answer 20

Starts with a 4 carbon molecule
AcetylCoA is joined, to form a 6 carbon molecule
The 6 carbon molecule has 2 CO2 leave, as well as NADH, FADH and ATP produced (from NAD, FAD and ADP + Pi)
This occurs 2 rimes for every glucose molecule- they produce 2 pyruvates each

Question 21

Products from Krebs cycle?

Answer 21

2 ATP
4 CO2
2 NADH
2 FADH

Question 22

Where does the electron transport chain occur?

Answer 22

Between the matrix of the mitochondria and the inter membrane space

Question 23

Other name for electron transport chain

Answer 23

Oxidative phosphorylation

Question 24

Electron transport chain process?

Answer 24

The NADH and FADH go to specific binding sites, hydrogen actively transported to intermembrane space
NAD and FAD return to Krebs cycle / link reaction/ glycolysis
The hydrogen ions create a concentration gradient, so diffuse through the ATP synthetase, producing ATP from ADP + Pi
The hydrogen ions combine with the electron that has been transported down the chain and oxygen (the final electron acceptor) producing water

Question 25

Mitochondria adaptation for electron transport chain specifically?

Answer 25

Densely packed cristae, allowing for a greater SA:V, for attachment of enzymes/ proteins during process

Question 26

Why does cyanide harm body?

Answer 26

Cyanide is a non competitive inhibitor of the final enzyme in electron transport chain. This means that the hydrogen ions, oxygen and electrons cannot form water, so ‘backs up’, preventing respiration.

Question 27

Why anaerobic respiration occurs during exercise?

Answer 27

Oxygen is used up more readily than supplied and an oxygen debt occurs. It is essential for muscles to still work despite lack of oxygen (organism fleeing predator)
At some point lactate needs to be converted back to pyruvate, when oxygen is available again