Metabolism and Energy

Question 1

what is metabolism

Answer 1

the set of chemical reactions that happen in living organisms to maintain life

Question 2

metabolism is usually divided into what two categories

Answer 2

catabolism

anabolism

Question 3

define catabolism

Answer 3

breaks down organic matter;. for example to harvest energy in cellular respiration

Question 4

define anabolism

Answer 4

uses energy to construct components of cells such as proteins and nucleic acids

Question 5

energy metabolism occurs via ___ production pathways

Answer 5

ATP

Question 6

energy (ATP) demand is set by the activation of muscle contraction

Answer 6

1) myosin ATPase type (the fiber type) and SERCA protein type
- MHC 1 or MHC IIx ect
- SERCA1a or SERCA2a

2) the peak force and mechanical nature of contraction
- isometric, isotonic ect

Question 7

when you start to do work your muscles use energy (ATP) at a rate that matches the work load demand of the activity. ATP demand is set by

Answer 7

the activation of muscle contraction

Question 8

typically the amount of ATP need to perform a standard workload is similar or different between trained or untrained individuals

Answer 8

similar between trained and untrained individuals

Question 9

what is ATP homeostasis

Answer 9

the balance of energy utilized by cellular ATPases and energy produced by metabolic pathways

Question 10

at rest ATP utilization =

Answer 10

0.01 umol ATP/g muscle/second

Question 11

during exercise ATP utilization =

Answer 11

10umol ATP/g muscle/second

Question 12

the net depolarization of ATP in muscle rarely goes below ___% why?

Answer 12

30

because ATP utilization pathways are tightly coupled to ATP metabolic pathways

Question 13

what are the three ways ATP is created (3 delivery systems)

Answer 13

1) high energy phosphate transfer (anaerobic pathways )
2) glycolysis (anaerobic pathway)
3) oxidative phosphorylation (aerobic pathways)

Question 14

does high energy phosphate transfer use O2

Answer 14

no

Question 15

what is high energy phosphate transfer

Answer 15

transfer of a phosphate group from phosphocreatine to ADP to regenerate ATP

Question 16

does glycolysis use O2

Answer 16

no

Question 17

what is glycolysis

Answer 17

degradation of glucose or glycogen (glycogenolysis)

Question 18

what is oxidative phosphorylation

Answer 18

complete combustion of fats and or CHOs

Question 19

does oxidative phosphorylation use O2

Answer 19

yes

Question 20

high energy phosphate transfer is anaerobic ____

Answer 20

alactic

Question 21

what are the steps of high energy phosphate transfer

Answer 21

ATPase
creatine kinase
adenylate kinase
AMP deaminase

Question 22

what is the ATPase reaction

Answer 22

ATP +H2O converts through ATPase to ADP +Pi +H + ATP

Question 23

what is the creatine kinase reaction

Answer 23

ADP +PCr + H ATP + Cr(PCr stores 3-4x greater then stored ATP)

Question 24

what is the adenylate kinase reaction

Answer 24

ADP + ADP ATP + AMP

Question 25

AMP deaminase reaction

Answer 25

AMP —> IMP + NH3

Question 26

what are the 2 segments of glycolysis

Answer 26

energy investment

energy generation

Question 27

glycolysis can power about ___ seconds of contraction

Answer 27

30 seconds

Question 28

if you start with glycogen how many ATP used in the energy investment stage of glycolysis is used

Answer 28

1

Question 29

what are the three stages of oxidative phosphorylation

Answer 29

1) formation of acetyl-CoA
2) oxidation of acetyl groups
3) oxidation of NADH and FADH2 in the electron transport chain

Question 30

explain the formation of acetyl-CoA

Answer 30

from carbohydrates via glycolysis or from fats via beta-oxidation or in extreme conditions from amino acids

Question 31

explain oxidation of acetyl groups

Answer 31

in krebs cycle to form NADH and FADH2

Question 32

explain oxidation of NADH and FADH2 in the electron transport chain

Answer 32

this process harnesses electrons to generate a proton gradient to power the formation of ATP from ADP and Pi

Question 33

what is the difference between untrained and trained HEPT

Answer 33

untrained
- accumulation of ADP is countered by HEPT + glycolysis (ADP accumulates)

trained
- HEPT + glycolysis are not relied upon quite as heavily after training

Question 34

why is HEPT + glycolysis not relied on as much in trained athletes

Answer 34

because oxidative phosphorylation is able to contribute to the removal of ADP sooner during exercise

Question 35

what is the difference between untrained and trained oxidative phosphorylation

Answer 35

untrained
- it is activated and makes enough ATP to fuel the contractions

trained
- activated much earlier!

Question 36

why does the oxidative phosphorylation activate much earlier in the trained state

Answer 36

due to an increase in mitochondria, an increased sensitivity of metabolic enzymes for ADP and an increase in oxygen delivery to working muscle. collectively these parameters contribute to a tight coupling of ADP production with ATP regeneration

Question 37

does oxidative phosphorylation remain elevated in both the train and untrained state after exercise stops?

Answer 37

yes

untrained
- in order to remove ADP by regenerating PCR

trained
- in order to remove ADP by regenerating PCR. however the total ADP content is less in a tightly coupled system so the oxygen debt is paid back much faster