intermediary metabolism

Question 1

what is intermediary metabolism

Answer 1

• enzymatic processes in living cell
• degradation or synthesis of carb, lipid protein
• rreaction betwwen the absorption of feedstuff and excretion of end products
• energy produced in form of heat and atp

Question 2

biological oxidation

Answer 2

• oxidative process, mainly in mitochondria
• chemical energy atp, heat, co2, h2o production
• respiratory chain

Question 3

anabolism and catabolism

Answer 3

• metabolism is complete set of chem reactions
• catabolism: yields energy, ex: break down of food in bilological oxidation
  . anabolism: uses energy to construct components o cells

Question 4

metabolic pathways

Answer 4

• catabolism
• rate limiting step
• anabolism¨
• amphiobolic reactions

Question 5

catabolism

Answer 5

• degradation to form energy
• large number of substrates degraded to acetyl CoA, ending up in citric cycle
• electron transport system undergo oxidative phosphorylation

Question 6

rate limiting step

Answer 6

slowest reaction in a pathway

- detrmines rate of pathway

Question 7

energy comes from? (catabolic)

Answer 7

• reduced molecules -> oxdized molecules + energy

- net product is atp

Question 8

anabolism

Answer 8

• synthetic processes

- biosythesis uses common internediate like pyruvate, acetyl CoA

Question 9

amphibolic reactions

Answer 9

involve catabolism and anabolism

Question 10

three stages of energy extraction

Answer 10

1. formation of smaller molecules
2. formation of simple units
3. citric acid cycle, respiratory chain and oxidative phosphorylation

Question 11

formation of smaller molecules

Answer 11

• fats, proteins, polysaccharides
  . breaking down polymers into iindividual units in gastrointestinal tract
• fatty acids, glucose, amino acids

Question 12

formation of simple units

Answer 12

• primarily acetyl CoA in different organs

-

Question 13

citric acid cycle, respiratory chain and oxidative phosphorylation

Answer 13

• cc - NADH+H+ and FADH2 prod
• further oxidation of acetyl CoA in cc result in rc and oxp
• generating ATP

Question 14

compare combustion and biological oxidation

Answer 14

• similarity: end products are co2 and h2o
  . difference: bio ox 40% of produced energy is stored as chem energy atp
• combustion heat and light is produced

Question 15

two methods of producing atp from substrates

Answer 15

1. oxidative phosphorylation - forming atp by a proton motive force
2. substrate level phosphorylation - direct phosphorylation of adp from phosphorylated intermediates.

Question 16

phosphoanhydride bonds

Answer 16

large negative free energy change of hydrolysis, thus high energy bonds

Question 17

high energy bonds

Answer 17

• represented by ~ symbol
• ~P is a p group with high free energy of hydrolysis
• compounds with high energy bonds have high group transfer potential
• two can be removed from atp - adp - amp

Question 18

function of atp and amp

Answer 18

• atp serve as energy source, hydrolytic cleavage related to energy requiring reaction
• amp function as energy sensor and regulator of metabolism
• amp stimulates metabolic pathways to produce atp

Question 19

high energy bonds in phosphocreatine

Answer 19

• phosphocreatine has high energy phosphate linkage
• used in nerve and muscle cells for storage of ~p bonds
• creatine kinase catalyzes
• reversible reaction

Question 20

high energy bond in thioester

Answer 20

• thioester forms between a carboxylic acid and a thiol group
• thioesters are high energy linkages
• can react with carboxyl in acetic acid or fatty acid
• spontaneity of thioester cleavage is essential to role of coenzyme A as acyl group carrier

Question 21

energy change of phosphate hydrolysis

Answer 21

• phosphocreatine: -43.1 kj/mol
• thioester bonds: -31,48 kj/mol
• atp (to adp): -30.6 kj/mol