Respiration

Question 1

What evidence is there for evolution in relation to Respiration

Answer 1

All Respiration produces ATP

But different Respiratory substances

Question 2

What cells respire

Answer 2

All eukaryota

Question 3

What stages make up aerobic Respiration

Answer 3

Glycolysis
Link reaction
Krebs cycle
Electron transfer chain

Question 4

What stages are in anaerobic Respiration

Answer 4

Glycolysis

Oxidation of reduced NAD

Question 5

Describe glycosis

Answer 5

Glucose is phosphorylated to phosphorylated glucose using 2 ATP

Hydrolysis using water to produce triose phosphate

Oxidation to pyruvate using 2 ADP and 2 NAD per triose phosphate

Question 6

Why must glucose be phosphorylated in glycolysis

Answer 6

Glucose isn’t very reactive

Phosphorylation allows glucose to be hydrolysed and oxidised

Question 7

What is a coenzyme

Answer 7

Organic molecule need for some enzymes to function

Question 8

Describe the link reaction

Answer 8

Pyruvate is oxidised to acetate
Requires 1NAD and produces 1 co2

Combined with coenzyme a to produce acetyl Coenzyme a

Question 9

Where does glycolysis occur

Answer 9

Cytoplasm

Question 10

Where does the link reaction occur

Answer 10

Mitochondrial matrix

Question 11

How does pyruvate move from the cytoplasm to where the link reaction occurs

Answer 11

Active transport using carrier proteins

Question 12

What is the function of the link reaction

Answer 12

To link glycolysis and Krebs cycle

Question 13

Overall what is produced in glycolysis of one glucose

Answer 13

2 ATP
2 reduced NAD
2 pyruvate

Question 14

Overall what is produced by the end of the link reaction for one glucose

Answer 14

2 ATP
2co2
2 acteyl coenzyme A
4 reduced NAD

Question 15

Where does the Krebs cycle occur

Answer 15

In the mitochondrial matrix

Question 16

Describe the Krebs cycle

Answer 16

Acetyl coa is combined with oxaloacetate to produce citrate and coenzyme A

A series of redox reactions producing 1 ATP 3 reduced NAD and 1 reduced FAD and 2 co2 coverts citrate to oxaloacetate

Question 17

How is ATP produced in the Krebs cycle

Answer 17

Substrate level Phosphorylation

Question 18

Overall what is produced up to the Krebs cycle for one glucose

Answer 18

4 ATP 10 reduced NAD 2 reduced FAD 6co2

Question 19

What’s the importance of the Krebs cycle

Answer 19

Breaks down macro molecules into micro molecules (acetyl coa to co2)

Provides reduced coenzymes for the Etc

Regenerates oxaloacetate which would otherwise accumulate

Source of immediate compounds for manufacture of Amino acids and fatty acids

Question 20

Wher is the energy released in the Etc stored

Answer 20

In electrons as potential energy

Question 21

What does ETC stand for

Answer 21

Electron transfer chain

Question 22

What is need for the ETC

Answer 22

Reduced Coenzymes
Cytochromes
Oxygen
ATP synthase

Question 23

Describe how the ETC works

Answer 23

Reduced NAD releases electrons and protons

Electrons enter the ETC via Cytochromes. As electrons are passed along via redox reactions energy is released

Energy used to pump protons into intermembranal space where conc increase creating gradient

Protons diffuse down gradient back into matrix via ATP synthase using facilitated diffusion releasing energy required to synthesis ATP.

Protons and electrons recombine with oxygen to form water

Question 24

What theory is used to explain the ETC

Answer 24

Chemiosmotic theory

Question 25

By what method is ATP synthesised

Answer 25

Oxidative Phosphorylation

Question 26

Explain the importance of oxygen in the ETC

Answer 26

Acts as terminal/ final electron acceptor Wihtout it electrons would accumulate and reduced NAD would not be oxidised to NAD so links and Krebs stop working

Question 27

Describe how the movement of electrons in the ETC releases energy

Answer 27

Each successive cytochrome is a little lower in energy Electrons move down energy gradient Energy released in small amounts preventing heat loss

Question 28

What Respiratory substrates may be used

Answer 28

Lipids Proteins glucose

Question 29

Describe how lipids are used as Respiratory substances

Answer 29

Lipid is hydrolysed into fatty acids and glycerol Glycerol into triose phosphate into glycolysis Fatty acids into acetate into link reaction

Question 30

Why do lipids release more energy than glucose in Respiration.

Answer 30

Many H produced means many reduced coenzymes

Question 31

Describe the Respiration of protein

Answer 31

Hydrolyse into Amino acids Deaminiation to remove amine group Converted into 3 carbon or 4/5 carbon chains 3c =pyruvate 4/5c = kreb cycle intermediates

Question 32

Describe what conditions would cause anaerobic Respiration in plants mad fugi

Answer 32

Water logged fields

Question 33

Describe anaerobic Respiration in plants and fungi

Answer 33

Glucose converted into pyruvate in glycolysis Pyruvate reduced into ethanol and co2 oxidising the NAD to produced NAD for use in glycolysis

Question 34

Describe conditions in which anaerobic Respiration would occur in animals

Answer 34

Extrenuous exercise

Question 35

Describe anaerobic Respiration in animals

Answer 35

Glucose to pyruvate in glycolysis Reduction of pyruvate to lactate via oxidation of reduced NAD to produce NAD for use in glycolysis

Question 36

How many ATP molecules produced from 1 reduced NAD

Answer 36

3

Question 37

How many ATP molecules produced from 1 reduced FAD

Answer 37

2

Question 38

What advantage is there to anaerobic Respiration in muscles

Answer 38

Immediate energy source = lactate PH levels restored

Question 39

What are the consequences of anaerobic Respiration

Answer 39

Reduction of PH due to lactic acid Denature of protein Less efficient ATP production (rate of glycolysis increases to compensate)

Question 40

What occurs after anaerobic Respiration once oxygen is reintroduced

Answer 40

Lactate converted into pyruvate or glucose and then glycogen

Question 41

How do you measure the rate of Respiration

Answer 41

Rate of O2 uptake or co2 production Using cappilary tube with dye.

Question 42

What measurements are needed to record rate of Respiration

Answer 42

Distance travelled by dye Diameter of tube Time Mass of organism

Question 43

What causes the dye to move in calculating rate of Respiration

Answer 43

Reduced O2 volume decreases the pressure causing the dye to be drawn towards the organism KOH needed to absorb co2 which would otherwise displace the O2