Metabolism Overview

Question 1

Metabolism

Answer 1

collection of couples and interlinked series of reactions which start with a specific mol and convert it to another

Question 2

What is the function of metabolism? (2)

Answer 2

~ extract biologically useful energy from the cell’s environment
~ synthesis building blocks of cells

Question 3

Catabolic reaction

Answer 3

~ breakdown
~ extraction of biologically useful forms of energy
e.g. fuel –> CO2 + H2O + energy

Question 4

Anabolic reaction

Answer 4

~ build-up/generate complex mols from simple ones

~ requires energy input

Question 5

Name the 6 types of enzyme catalysed reactions.

Answer 5

~ Oxidation-reduction - electron transfer
~ Ligation reaction - energy dependent
~ Group transfer
~ Isomerisation
~ Hydrolysis - adding water to break a bond
~ Lyase catalysed reactions - ATP independent

Question 6

Lyase

Answer 6

An enzyme that catalyses the breakdown of bonds [C=C or C ring]

Question 7

Describe the two types of lyases.

Answer 7

~ ANABOLIC - add group to C=C –> C-C

~ CATABOLIC - remove group from C-C –> C=C

Question 8

Name 3 ‘activated carriers’ and what they carry.

Answer 8

~ ATP - phosphate group
~ FADH2 - electrons
~ Acetyl CoA - acetyl unit

Question 9

Co-factor

Answer 9

a substance whose presence is essential for enzyme activity

Question 10

Activated carriers are… (3)

Answer 10

~ conserved through evolution
~ thermodynamically unstable
~ kinetically stable w/o catalysts

Question 11

What happens to the activated carriers w/o their catalysts?

Answer 11

~ NADH + FADH2 = resists oxidation + release of e-

~ ATP + Acetyl CoA = hydrolysed slowly - thus easy to transport

Question 12

What is ATP used for? (4)

Answer 12

~ motion
~ active transport
~ biosynthesis
~ signal amplification

Question 13

Which form are all C mol. converted to and why?

Answer 13

~ oxidised to CO2

~ as contains least energy