Ch 7: Metabolism Flashcards
anabolism
using energy to combine things
ex. condensation reactions w to from triglycerides, protein and poly/disaccharides
catabolism
breakdown of 2 things to produce energy
ex. hydrolysis
what do enzymes do?
- facilitate reactions
- remain unchanged after reaction: they are proteins
what do coenzymes do?
work with enzymes
- required for enzymes to function
- not proteins
where does the citric acid cycle occur?
in mitochondria
- aerobic process
what is the chemical structure of pyruvate?
3-C structure, used to make glucose, is also the byproduct of the breakdown of glucose during glycolysis
chemical structure of Acetyl CoA
2-C structure, can’t make glucose
- the breakdown produces ATP
all energy yielding nutrients are broken down to form what compound?
Acetyl CoA: its purpose is to make ATP in the mitochondria through the TCA
where does the electron transport chain occur?
in the mitochondria
- aerobic process
where does glycolysis occur?
what is the purpose?
an anaerobic process,
- happens in the cytosol
main purpose is to produce coenzymes for ETC
- also we get 2 pyruvate from 1 glucose splitting
LDH
lactate dehydrogenase
- near equilibrium reaction between lactate and pyruvate: whether is goes in one direction or the other depends on how much which one we have more of
- leads to anaerobic ATP production in the cytosol
PDH
pyruvate dehydrogenase
- pushes pyruvate to Acetyl CoA which goes to anaerobic production of ATP through TCA in the mitochondria
- irreversible process
2 fates of pyruvate:
1) make lactate (LDH) which becomes lactic acid
2) go into mitochondria and make ATP (PDH) through TCA
which metabolic reactions are not reversible?
what does this mean?
Acetyl CoA cannot produce pyruvate or amino acids
- this means that acetyl coA can produce fat but not protein
which metabolic reactions are reversible?
- pyruvate can be made into glucose in the liver
- amino acids can be made into pyruvate and vice versa
what things do we need to have in order to undergo aerobic ATP formation?
What is produced?
- ADP
- Pi
- O2
- NADH (coenzymes)
produced: water and CO2
can fatty acids yield glucose?
No, they go and produce acetyl coA instead
cause of inflammation (think oxygen)
if O2 doesn’t properly form to make H2O, it creates super oxides that can harm tissues
ketogenic vs glucogenic amino acids
ketogenic - amino acids that are converted into acetyl coA (non reversible)
glucogenic - amino acids that can be converted into glucose (and then to pyruvate) (reversible)
- thus can enter TCA directly
- these are most amino acids
ketosis
elevated ketoacids in the blood resulting in a lower pH
BUT if everything creates acetyl coA, does it matter where it comes from? No this the keto-diet is silly
2 options for Acetyl CoA
- it can enter the TCA cycle
- it can make fat
GLUT4
- is a glucose transporter
- mitochondria in cell will move towards a lipid droplet, toward capillaries where there is O2 or join one another throughout a muscle (fusion and fission) to replicate and share their DNA w one another
how long does it take to deplete glycogen stores in muscles when fasting?
24 hours
dangers of low carb diets?
-weight loss in not fat; it is water bc water is involved in the storage of carbs
how much ethanol is in a drink of alcohol?
15ml of ethanol
how does alcohol consumption disrupt the liver?
- causes an accumulation of NADH which is needed for ETC, this slows glycolysis and there is less acetyl coA for the mitochondria
- excess acetyl coA gets turned into fat resulting in a fatty liver = fibrosis = cirrhosis of the liver
- also decreases enzyme activity (ex. PDH)
health effects of alcohol consuption
arthritis (inflammation)
heart disease, cancer, etc.
