Respiration

Question 1

Describe glycolysis

Answer 1

Glucose is quite stable and therefore energy from aTP is needed to start the process. Pi from this ATP added glucose increasing reactivity of glucose so splits into 2x3C compounds.
Oxidised to pyruvate by removing 2 H atoms
Glucose has more energy so some is available to convert ADP back to ATP

Question 2

Describe Link Reaction

Answer 2

Pyruvate is decarboxylated and dehydrogenated
2C molecules bind with co-enzyme A to form acetyl coA
2 H released

Question 3

Describe Krebs cycle

Answer 3

Allows regeneration of 4C compounds
4C compounds and acetyl coA to form 6C.
CO2 and 2H released to form a 5C
CO2 and ATP released as well as 6 H
FAD --> red FAD by accepting 2H atoms

Question 4

Describe oxidative phosphorylation

Answer 4

Electron transport chain and chemiosmosis

Question 5

Describe electron transport chain

Answer 5

H atoms released from red NAD and red FAD enter chain and split into protons
electrons move down the transport chain releasing energy and is used by electron carriers to pump protons into intermembrane space
Conc gradient formed protons move down electrochemical gradient back into the matrix via ATP synthase
Movement of H+ across membrane which generates ATP is called chemiosmosis
H+ bind to oxygen, final electron acceptor
FAD and NAD return to krebs cycle

Question 6

Describe chemosmosis

Answer 6

Protons actively transported using energy from electrons
Inner membrane is impermeable to protons creating a conc gradient
H+ ions diffuse down through ATP synthase
ATP synthesis is catalysed
H+ ions change the shape of ATP synthase

Question 7

Describe production of lactate

Answer 7

without oxygen to accept H+ ions the red NAD are not oxidised so respiration cannot continue
However its possible to oxidise the reduced NAD
Pyruvate produced is reduced to lactate and the oxidised form of NAD is regenerated
Partially breaks down glucose for ATP

Question 8

How is a sprinter able to release sufficient enrgy for 100m sprint without enough oxygen

Answer 8

Energy is obtained from ATP which is already in muscle cells
ATP is also produced in glycolysis rapidly
Pyruvate is converted to lactate during anaerobic respiration
Fast twitch fibres

Question 9

What’s the effect of lactate build up?

Answer 9

pH cell falls inhibiting enyzmes due to affect its shapethat catalyse the glycolysis reaction

Question 10

Describe getting rid of lactate

Answer 10

Most lactate is converted back to pyruvate
Its oxidised directly to CO2 and water via krebs cycle releasing energy to synthesise ATP therefore oxygen uptake is greater than normal after exercise (oxygen debt)

Question 11

Describe the ATP/PC system

Answer 11

Immediate regeneration of ATP is achieved by CP stored in muscles. Hydrolysed to produce energy
CP+ADP –> Creatine +ATP