Anaerobic respiration

Question 1

what are the 2 types of anaerobic respiration

Answer 1

1) Alcohol fermentation- occurs in yeast cells
2) lactate fermentation- occurs in mammals

BOTH these places take place in the cytoplasm
BOTH start with glycolysis

Question 2

lactate fermentation

Answer 2

NADH transfers hydrogen to pyruvate to form lactate and NAD, which the NAD can then be used in glycolysis

Question 3

what happens if there is too much lactate and how does the body counteract this?

Answer 3

• too much lactate is toxic
• The liver takes up the lactate from the blood stream and converts it back into glucose, this process is called gluconeogenesis.

Question 4

what is gluconeogenesis

Answer 4

when there is too much lactate , it is converted into glucose

Question 5

Alcoholic Fermentation

Answer 5

-CO2 is removed from pyruvate to form ethanal
- NADH transfers hydrogen to ethanal to form:
ethanol and NAD

The NAD can then be reused in glycolysis

Question 6

why are the lactate and alcoholic fermentation processes both important, when oxygen levels are low?

Answer 6

This is because both processes regenerate NAD, so glycolysis can continue.

Question 7

why is ATP yield in anaerobic respiration lower than in aerobic respiration?

Answer 7

• This is because anaerobic respiration only has one energy releasing stage ( glycolysis) , this stage produces 2 ATP per glucose molecule
• krebs , oxidative phosphorylation need oxygen , so cant occur during anaerobic respiration.

Question 8

respiratory substrate def

Answer 8

Any biological molecule that can be broken down in respiration to release energy.

Question 9

why do different molecules have different energy values?

Answer 9

• most ATP is made in oxidative phosphorylation, which requires hydrogen atoms from NADH and FADH
• So respiratory substrates that contain more hydrogen atoms per unit of mass , PRODUCE MORE ATP when respiring.

Question 10

what is the order of energy values for different respiratory substrates? ( Highest to lowest)

Answer 10

• lipids………..proteins………carbohydrates
  lipids= 39.4
  proteins= 17
  carbs= 15.8

Question 11

Respiratory quotient formula

Answer 11

RQ= volume of CO2/ volume of O2

Question 12

respiratory quotient values for different respiratory substrates

• why do lipids and proteins have an RQ value lower than one?

Answer 12

lipids=0.7
proteins= 0.9
carbohydrates=1

• This is because more oxygen is needed to oxidise these lipids and proteins.

Question 13

what does a high RQ value mean ( higher than 1)

Answer 13

that the organism might be short on oxygen, and has to respire anaerobically and aerobically.