week 2 Flashcards
define energy
ability to do work
what are the 3 forms of energy and describe them
mechanical energy: mvmt of an object of potential to move
chemical energy: energy stored in the bonds of a molecule
thermal energy: energy due to the vibrations of molecules
what CAN energy do and what can energy NOT do
2nd law of thermodynamics:
energy CAN be transformed (converted) or transferred (passed on)
1st law of thermodynamics:
energy CAN NOT be created or destroyed
what units is energy measured in
the same units as work: joules and calories
list some examples of biological work
- muscle contraction
- synthesizing things
- pumping ions against their electrochemical gradient
define anabolism vs. catabolism
anabolism: building things up
catabolism: breaking things down
define endergonic vs. exergonic
endergonic: energy absorption
exergonic: energy release
define metabolic rate (MR)
energy cost per unit time
what are the 3 macronutrients that we eat, digest, store and harness energy from
- carbohydrates
- fats/lipids
- protein
what is MR influenced by
- maximal MR
- increased/decreased activity MR
- thermogenesis
- resting MR (RMR)
- basal MR (BMR)
is the conversion of ATP to ADP exergonic or endergonic
it is exergonic because ATP is releasing energy
what are the three different energy systems that we can use to resynthesize ATP
anaerobic pathways:
1. phosphagen system
- immediate system
- very fast but runs out quick
- energy from phosphocreatine
2. anaerobic glycolysis
- short-term system
- fast but makes a mess
- energy from CHO
aerobic pathways:
3. cellular respiration
- long-term system
- slow, steady, reliable
- energy from CHO, lipids, protein
true or false: all energy systems are running at all times
true!
what is the law of conservation of mass
matter is conserved, but transformed
what is the 1st law of thermodynamics
energy is conserved, but transformed
what is the 2nd law of thermodynamics
in all transformations, some USABLE energy will always be lost as heat
describe the phosphagen system
system with the highest power but the lowest capability. it is the primary pathway for strength, power and sprint
what is the creatine kinase reaction and where does each aspect of it come from
PCr + ADP -> ATP + Cr
PCr: phosphate donor and the energy source
creatine kinase is the enzyme that helps to catabolize PCr
- P is released
- Energy is released
Energy is used to bind P to ADP, forming ATP
Cr is leftover and can get recycled back into PCr
what is the myokinase reaction
ADP + ADP -> ATP + AMP
myokinase is the enzyme
AMP = adenosine monophosphate
define glycolysis
the catabolism (breaking down) of sugar (glucose)
involves splitting of a glucose molecule into two pyruvate molecules
net release of energy, which is used to resynthesize ATP
what pathway is used w/ sufficient oxygen vs. w/ insufficient oxygen
sufficient O2: aerobic glycolysis
insufficient O2: anaerobic glycolysis
REVIEW GLYCOLYSIS
what is phosphorylation
adding Pi to any molecule
describe the investment phase
cost: 2 ATP/glucose or 1 ATP if using glycogen
Pi transferred from ATP to glucose - energy released from cleaving ATP is transferred to higher-energy intermediate
REVIEW SUBSTRATE LEVEL PHOSPHORYLATION
REWATCH 2ND WEEK 2 SLIDESHOW FOR GLYCOLYSIS STUFF
describe the pay-off phase
makes 2 ATP/pyruvate, 4 ATP/glucose, and 4 ATP if using glycogen
Pi is transferred from the intermediate molecule to ADP. The energy released from the conversion of higher to lower energy intermediate used transferred to ATP
describe phosphofructokinases role in glycolysis
in glycolysis, PFK is the rate-limiting enzyme
- ADP and Pi activate PFK - indicate we are short on ATP
- ATP and PCR inhibit PFK - indicate we are well stocked
- citrate inhibits PFK - a sign that fats are being metabolized
- H+ inhibits PFK - not a helpful signal - just a consequence of acidity
what are 2 things that influence glycolytic rate?
- substrate availability
- NAD+ availability
