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Question 1

Answer 1

Only enough ATP for 1 second

Question 2

Characteristics of anaerobic exercise and examples

Answer 2

• high intensity
• rapid generation of force
• short periods

• examples
- sprinting
- weight-lifting

Question 3

Characteristics of aerobic exercise and examples

Answer 3

• low intensity
• prolonged, sustained exercise

e.g.
- long-distance running
- swimming
- walking

Question 4

Approximate contribution of aerobic and anaerobic energy sources to total energy production in events of different durations involving maximal work

Answer 4

Longer = more aerobic and less anaerobic %
Shorter = less aerobic and more anaerobic %

The longer you exercise the more aerobic it must be

Question 5

The longer you exercise the more ______ it must be

Answer 5

The longer you exercise the more aerobic it must be

Question 6

What ways has muscle of regenerating ATP from ADP?

Answer 6

Anaerobic exercise: Does not require O2
• phosphocreatine
• glycogen

Aerobic exercise: Requires O2
• oxidation of glucose and fatty acids
(Oxidative phosphorylation to get ATP needs O2 as the terminal acceptor)

Question 7

Phosphocreatine features

Answer 7

• is “on site”, “fast fuel”
• 20 µmol per g muscle
• is a ‘high-energy phosphate’ compound (there is a bond
that can be hydrolysed to make ATP)
• phosphate can be transferred to ADP to make ATP

Made from Gly, Arg and Met (in liver but transferred to muscle)
20 µmol/g — lasts ~10 s
- Energy buffering system

Question 8

Answer 8

• creative can be converted back if ATP is available
• excess creative is excreted in urine (can test if kidneys are \
  functioning)

Question 9

Creatine

Answer 9

• there is a relationship between how much creative is in your muscles and how long you can stay on a bicycle
• but nothing to do with long distance running

Question 10

Glycogen - features of how it is a fuel in anaerobic exersie

Answer 10

• is an ‘on-site’ store of glucose in muscle
• is mobilised to glucose 1-phosphate by glycogen
phosphorylase
• glucose 1-phosphate is converted to glucose 6-
phosphate
• glucose 6-phosphate is the fuel for anaerobic glycolysis

Question 11

How glycolysis is activated via adrenaline on muscle cell

Answer 11

• Adrenaline binds to beta adrenergic receptors on muscle cells
• when the hormone binds, a protein is bound to the receptor (GTP binds to the receptor) and there is a conformational change that releases the protein
• this protein then interacts with membrane bound adenlyte cyclase which will convert ATP into cAMP
• the GTP attached to the protein is hydrolysed back to GDP and will detach from the adenlyte cyclase
• if the hormone is still bound to the receptor, the protein can reaccociate with the receptor and bind another GTP, and reaccocaite with adencyclease again and make more cAMP
• will build up cAMP as long as the adrenaline is bound the the receptor
• the cAMP activates a kinase which phosphrilayes another kinase etc, then glycogen phosphrilayse is activated and will cleave off a glucose from glycogen

Question 12

Adrenaline binds to beta adrenergic receptors on muscle cells which stimulates…

Answer 12

the mobilisation of glycogen to provide fuel for glycolysis

Question 13

Answer 13

• lactate is acidic, it builds up and the you get fatigue and the acidic it’s interrupts muscle contraction and slows down the key enzyme in the glycosidic pathway - phosphofukatkinisase

Question 14

Anaerobic Glycolysis features

Answer 14

• muscle glycogen source of fuel
• O 2 not required
• ATP generated by substrate-level-phosphorylation
• pyruvate reduced to lactate to regenerate NAD+
• ATP generation very rapid but for short time only
• lactate can cause muscle pH to drop, thus fatigue

Question 15

What is glycogen mobilisation stimulated by in excercising muscle?

Answer 15

by Ca++ and adrenaline (stress hormone)

(Calcium also helps with contraction)

Question 16

Regulation of glycolysis in exercising muscle - what’s happening with phosphofructokinase activity

Answer 16

phosphofructokinase activity is increased by allosteric
regulators:
+ AMP
+ Pi

Question 17

Where do we get AMP from? How do muscles make good use of ADP?

Answer 17

ADP + ADP = ATP + AMP
adenylate kinase (myokinase)

AMP can then and go and upregulate glycolysis to get things through glycolysis faster

Question 18

Aerobic Generation of ATP by oxidation of glucose and fatty acids

Answer 18

• blood supplies fuels
• blood supplies O2
• active citric acid cycle
• electron transport chain oxidative phosphorylation

Question 19

Why is the inner mitochondrial membrane less permeable the the outer in the mitochondria ?

Answer 19

Cos u don’t want protons to go across it

Question 20

What’s carnitine up to?

Answer 20

• there is an enzyme in inner mitochondrial membrane which covalently attached the acryl chain to carnatine
• protein called carnotineacyltransfertase carrier and moves it into the matrix where another enzyme cleaves the FA and acetyl-carnatine and re-estifys the CoA to the FA chain for beta oxidation
• carnatine then pushed back out for reloading

We can make carnatine in our bodies and is in our diet
- therefore taking a supplement wont doing anything unless ur removing from heart surgery

Question 21

Aerobic Generation of ATP by oxidation of glucose and fatty acids - marathon example

Answer 21

Balance of aerobic but save a little anarobic
- need to know how much anarobic u have to save for the last sprint dash

Question 22

Aerobically trained rely less on glycogen “top up”

Answer 22

• dip into glycogen content later allowing you to go further

Question 23

Answer 23

Glycogen keeps ya going for longer

Question 24

Which is anarobic and which is aerobic ? Type 1 fibres and type 2 fibres

Answer 24

Type 2 is anaerobic

Question 25

Answer 25

Question 26

Answer 26

Muscle is specialised for the function - develop correct muscle for training for the right excerise

Question 27

Muscle adaptations to endurance training

Answer 27

• Selective hypertrophy of Type I (aerobic) fibres • Increased number of blood capillaries per muscle fibre • Increased myoglobin content • Increased size and number of mitochondria; increased cristae • Increased capacity of mitochondria to generate ATP by oxidative phosphorylation • Increased capacity to oxidise lipid and carbohydrate

Answer 28

Question 29

Time course of training and detraining adaptations in mitochondrial density in skeletal muscle

Answer 29

Question 30

Performance enhancing drugs

Answer 30

• EPO doping (erythropoietin increases red blood cell count – give you more O2) – recombinant EPO • Anabolic steroids (more muscle) • Growth factors (more muscle) – recombinant IGF-1, GH

Question 31

Will gene therapy be appropriated? - improving muscle content

Answer 31

The below transcription factors control the genes (upregulate transcription) for development of mitochondria