FOUNDATION-metabolism Flashcards
what is glycogenesis?
glucose——->glycogen
what is glycogenolysis?
glycogen——->glucose
what is glycolysis?
glucose——–>pyruvate
what is gluconeogenesis?
amino acids and fatty acids——>glucose
what is the process that converts fatty acids to acteyl CoA and what does this then enter?
BETA OXIDATION
-goes on to enter krebs cycle
which process is the only one that can occur anaerobically as well as aerobically?
glycolysis
which pathway comes off from Glucose-6-phosphate, and what does it convert?
pentose phosphate
-converts NADP+ into NADPH
where is glucose stored?
liver and muscles as glycogen
where is glucose released from in a state of hypoglycaemia?
only the liver
where are triglycerides stored?
liver and adipose tissue
where does glycolysis take place?
cytoplasm
how many ATP molecules are gained in glycolysis?
2ATP
what are the products of glycolysis?
pyruvate
where does the krebs cycle take place?
inner mitochondrial matrix
what is the beginning reaction of the krebs cycle?
oxaloacetate + acetyl group=citrate (6c)
how is ATP made in the krebs cycle?
substrate phosphorylation
where does oxidative phosphorylation take place?
-inner mitochondrial membrane
what is oxygens role in oxidative phosphorylation?
final electron transporter
which step in the respiration chain generates the most ATP?
oxidative phosphorylation
-34 atp molecules
what is catabolism?
breakdown of molecules
-mostly oxidative=release energy
eg oxidative phosphorylation
what is anabolism?
requires energy to reduce substances and build them into larger molecules
eg protein synthesis
what is energy coupling?
one system provides energy to power another system
what are exergonic reactions?
release energy into the surrounding environment
what are endogenic reactions?
takes energy from the surrounding environment
how does fatty acid chain length affect what can happen in lipolysis?
- short and medium fatty acids can enter mitochondria directly
- long chain fatty acids are shuttled into mitochondria a using a carnitive carrier-proteins
what is the molecule that amino acids, fatty acids, glucose and glycerol metabolised into after digestion?
Acetyl CoA
what is an amphibolic reaction? Give an example.
both anabolic and catabolic
eg Krebs cycle
what are the products of the krebs cycle?
- 2atp
- FADH2/ NADH-for ETC
what is the role of FADH2/ NADH in oxidative phosphorylation?
- oxidation (FADH2—>FAD and NADH—>NAD) drive movement of e- down etc
- drives H+ across membrane
- H+ leave intermembrane space via ATPsynthase
- ADP +Pi—–>ATP
what are the steps of glucose in carbohydrate metabolism?
GLUCOSE—->PYRUVATELACTATE
(anaerobic)
OR
GLUCOSE—–>PYRUVATE—->ACETYL COA—->TCA—->ETC
what are the other products of carbohydrate metabolism?
glucose into…
- glycogen (glucose-1-phosphate pathway)
- nucleic acid (pentose-phosphate pathway)
- amino acid synthesis (via pyruvate and TCA)
- glycerol of FAs
- cholesterol-acetyl coA
which process breaks down triglycerides into glycerol and fatty acids?
lipolysis
what occurs after lipolysis?
- fatty acids enter mitochondria (depending on size if too long then using carnitive proteins) as acyl CoA
- acyl CoA is oxidised in beta oxidation
- –>each cycle of beta oxidation reduced FA chain by 2 carbons-producing 2c acetyl CoA
- —>also produces reduced products to enter ETC
- —>continues until only 2c acetyl coa is left
- acetyl coa either converts into ketone bodies or enters TCA
outline the 2 types of amino acids
- glucogenic
- ketogenic
some can be both
what is the role of glucogenic aas?
convert to glucose via pyruvate
what is the role of ketogenic aas?
convert to acetyl CoA or ketone bodies-depending on body’s need
where are essential amino acids obtained?
diet
where are non-essential aas derived?
diet
transamination
what happens to excess amino acids?
catabolised to urea after deamination
what happens to the carbon skeleton of amino acids after transamination?
oxidised to co2 via TCA (glucogenic--->pyruvate--->acetyl coa) or forms glucose or forms ketone bodies
what is transamination?
process by which amino groups are removed from amino acids and transferred to acceptor keto-acids to generate the amino acid version of the keto-acid and the keto-acid version of the original amino acid.
describe features of metabolism in a fed state
- glycogenesis (more glucose stored as glycogen)
- glycolysis (glucose broken down into ATP)
- lipogenesis (triglyceride synthesis from FFAs)
- AA synthesis
which hormone promotes metabolism?
insulin
describe the features of metabolism in a starving state
- glycogenolysis-more glucose
- gluconeogenesis-more glucose
- lipolysis in adipose release FFAs and glycerol
- glycerol—>glucose
- moreoxidation of FFAs and ketone bodies for more energy
- protein/ aas—>glucose
