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Flashcards in Definitions Deck (30)
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1

Exergonic reaction

Catabolic.
The products have LESS energy than reactants (so change in energy, ∆G, is -ve)

2

Endergonic reaction

Anabolic
The products have MORE energy than reactants (so change in energy, ∆G, is +ve)

3

Metabolic pathway

Sequence of consecutive biochemical reactions.
The product of one reaction becomes the reactant of another.

4

Reciprocal regulation

The activation of one pathway while the opposite pathway is suppressed.

5

Allosteric enzymes

Relating to or denoting the alteration of the activity of an enzyme by means of a conformational change induced by a different molecule.
(Where the product concentration increases and that increase in product causes the product to bind to the enzyme in a different location and changes the conformation of the enzyme's active site and it can inhibit or promote the enzyme)

6

Feedback inhibition

When concentration of a product rises above required level, excess concentration inhibits enzyme activity (allosteric enzyme).
Production is stopped.
When concentration of that product drops below required level, production continues again.

7

1st law of thermodynamics

Amount of NRG in universe is constant - cannot be created or destroyed

8

2nd law of thermodynamics

In all natural processes, the entropy (disorder) of the universe increases.

9

Phosphoryl Group Transfer

The name given to the chemical process of the transfer of the phosphoryl group (PO3) from a phosphate ester or anhydride to a nucleophile.

10

Energy Coupling

Transfer of energy from catabolism to anabolism, or transfer of energy from exergonic process to endergonic process.
Free energy (from ATP hydrolysis) is coupled or functionally linked to the energy needs of another chemical reaction

11

Anabolism

The synthesis of complex molecules in living organisms from simpler ones together with the storage of energy

12

Catabolism

The breakdown of complex molecules in living organisms to form simpler ones, together with the release of energy

13

Metabolism

The chemical processes that occur within a living organism in order to maintain life.

14

Glycolysis

The breakdown of glucose (6C) to two pyruvate (3C)

15

Kinases

Enzymes that catalyse the transfer of the terminal phosphoryl group from ATP to an acceptor nucleophile.
(Subclass of transferases).
Kinases require Mg2+ for it's activity.

16

Gluconeogenesis

Producing glucose from non-carbohydrate sources once glycogen stores are depleted.

17

Glycogenolysis

Release of glucose (from glycogen break down) for ATP production

18

Glycogenesis

Storage of energy rich glucose (into glycogen).

19

Phosphorylation reaction

When a phosphate group is ADDED to a molecule

20

Isomerisation reaction

One molecule is changed into another with exactly the same atoms, just different arrangement

21

Isomerases

Catalyses the conversion of a specified compound to an isomer

22

Mutases

Enzyme of the isomerase class that catalyzes the shifting of a functional group from one position to another within the same molecule

23

Substrate Level Phosphorylation

Transfer of phosphate from a phosphorylated molecule to ADP forming ATP (so phosphate group is REMOVED from molecule)

24

Glycogen synthase

Involved in MAKING alpha 1-4 bonds between glucose units.

25

Branching enzyme

Involved in MAKING alpha 1-6 bonds between glucose units at the branch point.

26

Glycogen phosphorylase

Involved in BREAKING alpha 1-4 bonds between glucose units. Breaks glycogen up into glucose subunits

27

Debranching enzyme

Involved in BREAKING alpha 1-6 bonds between glucose units at the branch point.

28

Hexokinase

Phosphorylates hexose sugars forming hexose phosphates.

29

Chemiosmotic Theory

Transmembrane differences in proton concentration are the reservoir for the energy extracted from biological oxidation reactions.

30

Kinase

An enzyme that catalyses the transfer of a phosphate group from ATP to a specified molecule