Bioenergetics And Exercise Metabolism

Question 1

What is biogenetics

Answer 1

Flow and exchange of energy within a living system

Conversion of foods into usable energy for cell work

Question 2

What is metabolism

Answer 2

Sum of all chemical reactions that occur in the body

Question 3

What are anabolic reactions

Answer 3

Synthesis of molecules

Question 4

What are catabolic reactions

Answer 4

Breakdown of molecules

Question 5

Cellular chemical reactions:

Answer 5

Energy cannot be created or destroyed only transformed from one to another.

Endergonic: requires energy to be added to the reaction

Exergonic: releases energy

Question 6

What is a coupled reaction

Answer 6

Liberation of energy in an Exergonic reaction drives an endergonic reaction

Question 7

What is oxidation and reduction

Answer 7

Oxidation: removing an electron
Reduction:adding an electron

Question 8

What are enzymes

Answer 8

They are proteins that lower the energy of activation and accelerate chemical reactions

Question 9

How enzymes lower the energy of activation

Answer 9

1.Kinase: add a phosphate group
2.dehydrogenase: removal of hydrogen atoms
3.oxdiases: catalayzes oxidation reduction reactions involving oxygen
4.isomerases: rearrangement of the structure of molecules

Question 10

Describe anaerobic pathways

Answer 10

1. Does not involve oxygen
   2.phophocreatine breakdown and glycolysis

Question 11

Describe aerobic pathways

Answer 11

1.requires oxygen
2.oxidative phosphorylation
3.dependant on cardiovascular system and respiratory systems to provide oxygen

Question 12

Describe atp-pc system

Answer 12

Most rapid and simplest (one enzyme reaction) method of producing atp by phosphocreatine breakdown.

It has a limited capacity to produce energy, depleted after 10-15 seconds of all out activity

Question 13

Describe glycolysis

Answer 13

1.increases in the by products of atp that activates energy flux through reactions of glycoytix pathways
2.three fold higher than atp-pc system about 30-90 seconds.

Question 14

What needs to be available for glycolysis to continue

Answer 14

Adequate amounts of nad must be available to accept hydrogen

Question 15

Describe how NADH is formed

Answer 15

1. If sufficient oxygen is available hydrogen can be shuttled into mitochondria for atp production
   2.in the absence of oxygen, pyruvate can accept the hydrogens to form lactate

Question 16

What is the Krebs cycle

Answer 16

Completed oxidation of acetyl coa to provide electrons for the electron transports chain

Question 17

Describe how the Krebs cycle works

Answer 17

1.glycolysis generates 2 molecules of pyruvate
2.pyruvic acid enters the mitochondria and is converted to acetyl coa losing a carbon
3.acetyl coa combines with oxaloacetate to form citrate
4.series of reactions to generate oxaloacetate
5.each turn of the cycle, 1 atp molecule is synthesized from guanosine triphosphate with the release of high energy electrons

Question 18

What are rate limiting enzymes

Answer 18

1.found early in a metabolic pathway
2.activity is regulated by modulators

Question 19

What are the energy requirements at rest

Answer 19

1.almost 100% of atp produced by aerobic metabolism
2.blood lactate levels are low

Question 20

Describe rest to exercise transitions

Answer 20

1.ATP production increases immediately.
2.oxygen uptake rapidly increases
3. Initial atp production must be through anaerobic pathways which creates an oxygen deficit

Question 21

Why do endurance trained individuals have a lower oxygen deficit than untrained

Answer 21

1.better developed aerobic boienergetic capacity:
Greater regional blood flow to active muscle
2.increase mitochondrial volume in muscle fibres results in less lactate production at the beginning of exercise

Question 22

Excess post exercise oxygen consumption:

Answer 22

EPOC was coined to replace the term ‘oxygen debt’

Question 23

What is the rapid portion of EPOC

Answer 23

1. Resynthesis of stored PC in muscle
   2.replenishing muscle and blood oxygen stores

Question 24

What is the slow portion of EPOC

Answer 24

1.elevated heart rate and breathing increases oxygen demand
2.elevated body temp=increased metabolic rate
3.elevated blood levels of epinephrine and norepinephrine = increased metabolic rate
4.conversion of lactic acid to glucose