The Aerobic System

Question 1

what is the type of reaction?

Answer 1

aerobic

Question 2

what is the fuel used?

Answer 2

glycogen/glucose and fats

Question 3

what are the stages in this system

Answer 3

S1: aerobic glycolysis
S2: Kreb’s Cycle
S3: electron transport chain

Question 4

what are the reaction sites?

Answer 4

S1: sarcoplasm
S2: mitochondrial matrix
S3: mitochondrial cristae

Question 5

what are the controlling enzymes?

Answer 5

GPP, PFK, co-enzyme A, and lipase

Question 6

what is the ATP yield?

Answer 6

S1: 2 ATP
S2: 2 ATP
S3: 34 ATP

Question 7

what are the by-products produced

Answer 7

CO2 and H2O

Question 8

what is the intensity of this system

Answer 8

low-moderate/submaximal

Question 9

what is the duration of this system?

Answer 9

180 seconds onwards

Question 10

sporting example from individual activity

Answer 10

marathon, open-water swimming

Question 11

sporting example from team game

Answer 11

rugby forward to last the duration of the match

Question 12

advantage of this system

Answer 12

• large supply of glucose and glycogen
• high ATP yield 38:1
• no fatiguing by-product

Question 13

disadvantages of system

Answer 13

• aerobic so have to wait for O2
• complex series of reactions
• can only work at submax intensity
• takes a long time to breakdown fat (20 mins)
• requires 15% more O2

Question 14

S1: aerobic glycolysis

Answer 14

1) GPP breaks down glycogen into glucose
2) PFK converts glucose to pyruvic acid + energy
3) link reaction converts pyruvic into acetyl coA
4) energy used to resynthesise 2 ATP

Question 15

S2: Kreb’s Cycle

Answer 15

1) acetyl coA from S1 + oxaloacetic acid form citric acid
2) produces CO2, hydrogen+, and energy which is used to resynthesis 2ATP

Question 16

S3: electron transport chain

Answer 16

1) hydrogen from S2 split into H+ and H-
2) H+ and O2 form h2o
3) H- carried by electron carriers NAD and FAD to release energy used to resynthesise 34 ATP

Question 17

how does the aerobic system use fats as fuel?

Answer 17

lipase breaks down tryglycerides to produce free fatty acids and glycerol - FFAs converted into acetyl coA - acetyl coA continues through Kreb’s Cycle and ETC

Question 18

lactate threshold and OBLA

Answer 18

• sudden increase in conc. of lactic acid in blood at the anaerobic threshold
• the intensity of exercise where blood lactate conc. reaches 4 mmol/l is called OBLA