Lecture 18: Introduction to Metabolism

Question 1

Metabolism

Answer 1

• an interconnected web of biochemical reactions

Question 2

Series of reactions are

Answer 2

categorized into different metabolic pathways

Question 3

Main purpose of metabolism (3)

Answer 3

1. Generate energy
2. Produce important molecules
3. Eliminate toxic chemicals

Question 4

Anabolism

Answer 4

• building of complex molecules from numerous simple ones with useful energy (ATP)

Question 5

Catabolism

Answer 5

• the breakdown of complex molecules (fuel) into numerous simple ones

Question 6

Adenosine Triphosphate

Answer 6

Question 7

ATP to ADP process

Answer 7

Question 8

ATP to AMP

Answer 8

Question 9

How is free energy released?

Answer 9

ATP hydrolysis

Question 10

ATP is commonly

Answer 10

hydrolyzed to ADP

Question 11

ATP can be used to drive….

Answer 11

thermodynamically unfavourable reactions

Question 12

ATP is the key intermediate between….. they can……

Answer 12

• Phosporyl group transfer reactions.
• Can accept/donate phosphoryl groups from/to important metabolites

Question 13

After stored ATP and creatine phosphate is used up, ATP is….

Answer 13

• regenerated through aerobic and anaerobic metabolism

Question 14

As muscle ATP decreases….

Answer 14

creatine phosphate acts as a phosphoryl buffer and replenish the ATP supply

Question 15

Creatine Phosphate

Answer 15

a reserve of high-energy phosphate groups that can be used to rapidly generate ATP (adenosine triphosphate) during intense physical activity.

Question 16

—– reactions releases energy

Answer 16

oxidation

Question 17

most energy comes from molecules that are most …

Answer 17

• reduced

Question 18

Carbons in carbohydrates and fats is….

Answer 18

oxidized to CO2 one carbon at a time, and the energy released is used to regenerate ATP from ADP and Pi

Question 19

Oxidation:

Answer 19

lose electron (gain C-O bonds)

Question 20

Reduction

Answer 20

• gain electrons (Lose C-O bonds)

Question 21

Redox reaction

Answer 21

Transfer of e- between two molecules

Question 22

To determine if a molecule is oxidized or reduced:

Answer 22

• determine oxidation number
• count bonds to oxygen

Question 23

Increase in oxidation numbers mean

Answer 23

oxidation

Question 24

Decrease in oxidation numbers mean

Answer 24

reduction

Question 25

FInding oxidation via electronegativity:

Answer 25

Question 26

FInding oxidation via number of oxygen bonds:

Answer 26

Question 27

Activated carrier (5)

What it is+ ex

Answer 27

Molecule carrying a group that can be readily donated to other molecules. They may carry:
- Phosphoryl groups: ATP
- Electrons for fuel oxidation: Nicotinamide adenine dinucleotide (NADH), flavin adenine dinucleotide (FADH2)
- Electron for biosynthesis: nicotinamide adenine dinucleotide phosphate (NADPH)
- Two-carbon units: acetyl-coenzyme A (acetyl-CoA)

Question 28

Activated carriers of electron for fuel oxidation: NADH

reactive site + what happens

Answer 28

• NAD+ is not carrying electrons, NADH is carrying electrons

Question 29

Activated carriers of electron for fuel oxidation: FADH2

reactive site + what happens

Answer 29

Question 30

Activated Carriers of two-carbon units: Acetyl-CoA

Answer 30

Question 31

—- is the precursor to many activated carriers

Answer 31

Vitamin B

Question 32

Activated carriers (ATP, NADH, NADPH, FADH2 and acetyl-CoA) are kinectically stable this means… + stability results in…(2)

Answer 32

• they react very slowly without specific catalyst enzymes, aka they dont react spontaneously.
• This stability results in enzymes controlling the flow of metabolism

Question 33

Metabolis is —– to maintain —- and to respond to —–

Answer 33

• highly regulated
• homeostatsis
• changing environmental conditions

Question 34

Regulation of metabolism (3)

Answer 34

Question 35

The energy status of a cell controls metabolism. What is energy charge?

formula+what high EC mean

Answer 35

• Measure of how much energy is in a cell (cell’s energy status)