Metabolism Intro

Question 1

Metabolism Def

Answer 1

Sum of chemical reactions essential for life. 2 Types: Catabilic and Anabolic. All metabolic paths are linked (products produced in 1 are reactants in the other)

Question 2

Catabolic Reaction

Answer 2

Breakdown of large molecules to small releasing energy

Question 3

Anabolic Reaction

Answer 3

Forming large molecules out of small molecules. Requiring (taking in) energy

Question 4

Catabolism Stage 1

Answer 4

Hydrolysis (breaking of bonds) of large molecules into smaller molecules

Question 5

Catabolism Stage 2

Answer 5

Conversion of amino acids, fatty acids, glycerol or monosaccharides to Acetyl Co A (2 C chain)

Question 6

Catabolism Stage 3

Answer 6

Oxidation of acetyl Co. A. Oxidative phosphorylation (ATP generation). TCA cycle

Question 7

(Protein) Electron Carriers

Answer 7

NAD+, NADP+ and FAD. Undergo redox reactions in catabolic pathways (eg glycolysis, TCA)

Question 8

Amount of energy ATP Releases

Answer 8

-8 kCal/mol

Question 9

Free energy functions in cell

Answer 9

Mechanical (eg muscle contraction), transport (cell pumps), thermogenesis and biosynthetic (anabolic reactions)

Question 10

Anabolic forming of ATP

Answer 10

Oxidation of food stores

Question 11

Energetically Favourable Reactions

Answer 11

Substances go from high energy to low energy

Question 12

What encourages energetically unfavourable reactions in body

Answer 12

ATP and Enzymes. Enzyme inhibition and activation occur with different environmental changes to ensure metabolic pathways are only done to extent necessary

Question 13

Endergonic Reactions Def

Answer 13

Energetically unfavourable, positive delta G. Anabolic reactions (requires energy)

Question 14

Exergonic Reactions Def

Answer 14

Gavourable reaction, negative delta G. Catabolic, releases energy

Question 15

1st step of glucose metabolism

Answer 15

Glucose is phosphorylated (phosphate added) by glucokinase (hexokinase) to form glucose-6-phosphate. This is an unfavourable reaction made possible by ATP hydrolysis (adding of 2 delta G values in reaction results in net negative delta G)

Question 16

NAD+ and NADH relationship

Answer 16

NAD+ (oxidised) and NADH (reduced). A protein reactant is reduced and oxidised in relation to eachother (as NAD+ gains electrons and a proton the other reactant loses them)

Question 17

Last electron carrier in ETC

Answer 17

O2 (inner mitochondrial membrane)

Question 18

How do mitochondria signal other cells

Answer 18

Break down their Calcium stores

Question 19

What cell doesn’t contain mitochondria

Answer 19

Erythrocytes. ETS and TCA can’t happen

Question 20

TCA location

Answer 20

Matrix. Except for succinate dehydrogenase (enzyme shared with ETC) in membrane

Question 21

Amount of ATP per glucose produced in NADH pathways

Answer 21

38

Question 22

Amount of ATP per glucose produces in FADH pathways

Answer 22

36

Question 23

Where do products of TCA cycle end up

Answer 23

IN ETC

Question 24

What can be used as TCA cycle intermediates

Answer 24

amino acids

Question 25

Energy not converted to ATP in ETC Function

Answer 25

Thermogenesis, cell signaling (Ca store breakdown),

Question 26

Triglycerides as energy stores

Answer 26

High energy stores in adipose tissue. Breaks down to form acetyl co A and NADH

Question 27

Amino Acid as energy stores

Answer 27

Converted to pyruvate

Question 28

ATP production under anaerobic conditions

Answer 28

Only 2ATP per Glucose (Glycolysis only). Pyruvate converted to lactic acid

Question 29

Intermediate of glucose in glucogenesis

Answer 29

Oxaloacetate

Question 30

Intermediate fatty acids, cholesterol and ketone

Answer 30

Acetyl Co A

Question 31

Glucogenesis Def

Answer 31

Production of glucose from non-carbohydrate (protein and fat) substrates. Used to maintain blood glucose while fasting

Question 32

Amphibolic Def

Answer 32

Pathways that are both catabolic and anabolic. Eg TCA cycle

Question 33

Metabolic Pathway Regulation

Answer 33

Feedback (enzymes), phosphorylation, hormonal regulation (conc of hormones), allosteric regulation (changes enzyme function), substrate and oxygen availability

Question 34

Hypoxia Def

Answer 34

Low oxygen

Question 35

Anoxia Def

Answer 35

No oxygen

Question 36

Rate Limiting Enzyme Def

Answer 36

regulated by the most mechansims. Determines rate of enzyme eg phosphofructase 1

Question 37

Dehydrogenases Function

Answer 37

Removes H from 1 molecule and gives to other

Question 38

Kinase

Answer 38

Transfer phosphate from 1 molecule to another

Question 39

Consequnces of impaired enzyme action

Answer 39

Substrate accumulation (toxic), product deficency (disease), alternative product (toxic)