Week 2 Flashcards
Define metabolic pathways?
Biochemical reactions that occur in progression from the substrate to product, usually involving enzymes and cofactors
What is the difference between anabolic and catabolic pathways?
anabolic: builds molecules, use energy
catabolic: breaks down molecules, produce energy
What are the three steps of catabolism?
- digestion: break down of complex molecules to their component building blocks
- conversion of building blocks to acetyl CoA (or other simple intermediates)
- metabolism of acetyl CoA to Co2 and formation of ATP
What is an oxidation-reduction reaction?
The movement of electrons
Oxidised organic compounds
– Increased oxidation state or loss of electrons
Reduced organic compounds
– Decreased oxidation state or gain of electrons
How do enzymes control oxidation/reduction reactions
dehydrogenases remove hydrogen ions from energy-containing nutrients and donate them to oxygen to form water (and ATP is produced)
What do Niacin and riboflavin do?
help transport hydrogens from energy-yielding compounds to oxygen in metabolic pathways
What is the difference between anaerobic and aerobic respiration?
Anaerobic:
- no oxygen
- respiration of one glucose molecule= 2 ATP
Aerobic
- oxygen
- respiration of one glucose molecule= 32 ATP
What are the 4 steps of aerobic metabolism of glucose?
- Glycolysis (anaerobic step): Glucose is oxidized to pyruvate
- Pyruvate is metabolized to acetyl coenzyme A (CoA) by pyruvate dehydrogenase.
- Acetyl CoA enters citric acid cycle (CAC) producing NADH+ H+, FADH2, and CO2
- Electron Transport Chain: oxidative phosphorylation. ATP is derived from NADH + H+ and FADH2 as H+ travel down the concentration gradient from the intermembrane space via ATP synthase.
What is lipolysis?
Triglycerides broken down into free fatty acids and
glycerol
What is Beta-oxidation?
fatty acid oxidation
1 fatty acid made of 16 carbons makes how many ATPs?
106
how are fatty acid molecules turned into acetyl molecules?
beta-oxidation
Carbohydrates aid in fat metabolism to some extent. true or false?
true
What are the 5 stages of formation of ketone bodies?
- blood insulin drops
- lipolysis promoted and FA’s stores in adipose tissues are released
- FA’s taken up by the liver
- liver oxidized the FA’s to acetyl-CoA then to ATP
- when there is enough ATP, the liver cells combine 2 acetyl-CoA molecules together to form a 4 carbon molecule. this is further metabolized into ketone bodies
Define Ketogenesis
formation of ketones