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Flashcards in Introduction to Biochemistry Deck (32)
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1
Q

First law of thermodynamics

A

Energy is neither created nor destroyed

2
Q

Second law of thermodynamics

A

When energy is converted to a new form, some becomes unavailable to do work

3
Q

How is it possible for a +delta G reaction to occur

A

By pairing it with a -delta G reaction

4
Q

What are standard conditions

A

pH 7, 298 K, 1 atmosphere, I mol/l

5
Q

What delta value are readily reversible reactions near to.

A

Zero.

6
Q

What type of reactions are spontaneous, endergonic or exergonic

A

Exergonic

7
Q

What enzyme catalyses the conversion of glucose-6-phosphate to glucose-1-phosphate

A

Phosphoglucomutase

8
Q

NET gain of ATP from glycolysis

A

2 ATP

9
Q

What is the term given to the formation of new glucose from non-carbohydrate precursors

A

Gluconeogenesis. Remember, gluconeogenesis IS NOT simply the reverse of glycolysis

10
Q

What shape is a water molecule

A

Tetrahedral

11
Q

What type of substances do not dissolve in water - hydrophobic

A

Non-polar substances

12
Q

What characteristic of micelles allows them to dissolve in water

A

Their hydrophobic tails face inside, whereas their hydrophilic heads face outside

13
Q

What are stereoisomers

A

Non-superimposable mirror images of a molecule

14
Q

Give an example of a non-polar hydrophobic group

A

CH3 (methyl) groups

15
Q

What are the four ‘groups’ of amino acids

A

Polar, non-polar, acidic and basic

16
Q

In what direction do peptide chains extend in

A

From the N-terminal to the C-terminal

17
Q

What does the acid dissociation constant measure

A

The ability of an acid to donate a proton

18
Q

What is Ka

A

Ka = the acid dissociation constant. This equilibrium constant is a quantitative measure of the strength of an acid in a solution.

19
Q

What is the Henderson Hasselbalch equation used for

A

This equation links the Ka of an acid with the pH of a solution containing this acid. It can be used to calculate the properties of buffer solutions

20
Q

Under what circumstance will pH = pKa

A

When the concentration of an acid is equal to the concentration of conjugate base

21
Q

What are zwitterons

A

Electrically neutral molecules or ions

22
Q

At which point does a molecule have no net charge

A

The isoelectric point = pI

23
Q

Primary protein structure

A

The sequence of amino acids

24
Q

Secondary structure

A

The localised conformation of the polypeptide backbone

25
Q

Tertiary structure

A

3D structure of the polypeptide, including all of its sidechains

26
Q

Quaternary structure

A

The special arrangement of polypeptide chains in a protein with multiple subunits

27
Q

What are the 3 types of secondary protein structures

A

Alpha helix, beta sheets/stands and triple helix

28
Q

Symptom of weakened collagen

A

Bleeding gums

29
Q

What amino acid substitution causes sickle cell anaemia

A

Glutamic acid to valine

30
Q

Give 3 examples of conditions which arise when protein folding is slow and errors subsequently occur

A

Alzheimer’s, Parkinson’s and CJD

31
Q

Describe the structure of haemoglobin

A

4 subunits, two alpha and two beta chains, each with a haem group which can bind one oxygen each

32
Q

What is allosteric regulation

A

When the binding of one molecule changes the affinity for the other subunits (e.g. haemoglobin)