topic 7

Question 1

what is aerobic respiration

Answer 1

where a large amount of energy is released by splitting glucose

Question 2

what’s the overall equation for respiration

Answer 2

C6H12O6 + 6O2 ——–> 6CO2 + 6H2O + ENERGY
(GLUCOSE)

Question 3

what are the four stages of aerobic respiration

Answer 3

glycolysis, the link reaction, the Krebs cycle, oxidative phosphorylation

Question 4

what happen is glycolysis (simple)

Answer 4

makes pyruvate from glucose

Question 5

what are the two steps of glycolysis

Answer 5

phosphorylation and oxidation

Question 6

what happens during phosphorylation in glycolysis

Answer 6

glucose is phosphorylated by adding two phosphates from 2 molecules of ATP creating triose phosphate and ADP

Question 7

what happens during oxidation in glycolysis

Answer 7

triose phosphate is oxidised to form pyruvate. NAD collects the hydrogen forming NADH, 4ATP are produced but the net gain of ATP is two

Question 8

what happens in the link reaction (simple)

Answer 8

pyruvate is converted to acetyl coenzyme A

Question 9

how is pyruvate converted in the link reaction

Answer 9

pyruvate is decarboxylated, NAD is reduced collecting its hydrogen from pyruvate forming acetate, acetate is combined with coenzyme A to form acetyl coenzyme A

Question 10

how many times does the link reaction occur for each glucose molecule

Answer 10

twice

Question 11

what happens during the Krebs cycle (simple)

Answer 11

produces reduced coenzymes and ATP

Question 12

what happens during the third stage of the Krebs cycle

Answer 12

the 5C molecule is converted into a 4C molecule, decarboxylation nd dehydrogenation occur producing molecule of FADH and 2 molecules of NADH, ATP is produced by substrate phosphorylation

Question 12

what happens during the first step of the Krebs cycle

Answer 12

acetyl coA combines with oxaloacetate to form citrate

Question 13

what happens during the second step of the Krebs cycle

Answer 13

the citrate molecule is converted into a 5C molecule, decarboxylation occurs, dehydrogenation also occurs, the hydrogen is used to produce NADH

Question 14

what are the products of the Krebs cycle

Answer 14

1 cosenzyme A
oxaloacetate
2 CO2
1 ATP
3 NADH
1 FADH

Question 15

what happens during oxidative phosphorylation (simple)

Answer 15

lots of ATP is produced

Question 16

what are the two processes involved with oxidative phosphorylation

Answer 16

the electron transport chain and chemiosmosis

Question 20

how many molecules of ATP can be made from one glucose molecule

Answer 20

38

Question 21

what muscle is involved in movement

Answer 21

skeletal muscle

Question 22

what other body parts are included in movement

Answer 22

skeletal muscle, tendons, ligaments and joints

Question 23

how do skeletal muscles work

Answer 23

they contract and relax to move the bones at the joint, they work together in antagonistic pairs

Question 24

what are skeletal muscles made up of

Answer 24

they are made up of large bundles of long cells called muscle fibres

Question 25

describe muscle fibres

Question 26

what are myofibrils

Answer 26

long, cylindrical organelles found in muscle fibres

Question 27

what do myofibrils contain

Answer 27

thick myosin and thin actin filaments

Question 28

what are myofibrils made up of

Answer 28

many short sarcomeres

Question 29

what is the sliding filament theory and what does it explain

Answer 29

it explains muscle contraction, where the myosin and actin slide over one another to make sarcomeres contract- the myosin filaments themselves font contract and myosin and actin molecules stay the same length

Question 30

what is muscle contraction triggered by

Answer 30

an action potential

Question 31

how does the action potential cause muscle contraction

Answer 31

it triggers an influx of calcium ions, causing depolarisation, the calcium ions pulls out tropomyosin revealing the actin-myosin binding site. Ate moves the myosin head after it's attached to the binding site. this pulls the actin filament along.

Question 32

what are the features of slow twitch muscles

Answer 32

contract slowly, muscles used for posture, good for endurance activities, can work for long durations, lots of myoglobin and mitochondria

Question 33

what are the features of fast twitch muscles

Answer 33

contract quickly, used for fast movement, good for short bursts of exercise, get tired quickly, little mitochondria and myoglobin