Introduction

Question 1

What is entropy?

Answer 1

disorder

Question 2

Is free energy change positive or negative in exergonic reactions?

Answer 2

negative

Question 3

In endergonic reactions, is total free energy of products more or less than in reactants?

Answer 3

more

Question 4

Which type of reactions, exergonic or endergonic, can occur spontaneously?

Answer 4

exergonic

Question 5

What happens to free energy released as you move closer to equilibrium?

Answer 5

increases

Question 6

In readily reversible reactions (those close to equilibrium) what is the free energy change value?

Answer 6

close to zero

Question 7

Which free energy change values are good in reactions which are control points?

Answer 7

large negative values

Question 8

What type of free energy change value does conversion of ATP to ADP have?

Answer 8

large negative

Question 9

Does the forward reaction of Glucose-6-phosphate into glucose-1-phosphate have a positive or negative value for free energy change?

Answer 9

positive

Question 10

Is water polar or non polar?

Answer 10

polar

Question 11

What are water molecules like?

Answer 11

bent, form a dipole, tetrahedral shape

Question 12

What charge does hydrogen have?

Answer 12

partial positive charge

Question 13

What shape are hydrogen bonds?

Answer 13

linear

Question 14

In micelle formation what do the balls represent?

Answer 14

hydrophilic heads

Question 15

In micelle formation what do the zag zag lines represent?

Answer 15

hydrophobic tails

Question 16

What are the bonds between amino acids?

Answer 16

peptide

Question 17

From which terminal to which does the direction go in the peptide chain?

Answer 17

N terminal to C terminal

Question 18

What is the character and shape of peptide bonds?

Answer 18

partial double bond character
Peptide bonds are planar
Peptide bonds are strong and rigid
-important for folding of proteins

Question 19

Are acids proton donors or acceptors?

Answer 19

donors

Question 20

What is pH?

Answer 20

Measurement of the amount of protons in a solution

Question 21

What do amino acids without charged side groups exist as in neutral solution?

Answer 21

zwitterions with no net charge

Question 22

How many titratable groups do zwitterions have?

Answer 22

2

Question 23

What is the isoelectric pH?

Answer 23

The pH at which a molecule has no net charge

Question 24

Can the ends of proteins be ionised?

Answer 24

Yes

Question 25

Can proteins act as buffers?

Answer 25

Yes e.g. haemoglobin

Question 26

What is primary structure?

Answer 26

the sequence of amino acid residues

Question 27

What is secondary structure?

Answer 27

localised conformation of the polypeptide backbone

Question 28

What is tertiary structure?

Answer 28

the three-dimensional structure of an entire polypeptide, including all its side chains

Question 29

What is quaternary structure?

Answer 29

spatial arrangement of polypeptide chains in a protein with multiple subunits

Question 30

What break alpha helixes?

Answer 30

proline residues

Question 31

What component of bone and connective tissue is the most abundant protein in vertebrates?

Answer 31

collagen triple helix

Question 32

What can lack of collagen cause?

Answer 32

bleeding gums, scurvy etc

Question 33

Which are soluble in water, fibrous or globular proteins?

Answer 33

globular

Question 34

What are examples of fibrous proteins?

Answer 34

keratin, collagen

Question 35

Where do amino acids with hydrophobic side-chains tend to cluster?

Answer 35

centre of globular proteins

Question 36

What change occurs in sickle cell anaemia?

Answer 36

Single nucleotide sequence change in coding region of the b chain of haemoglobin A Results in altered protein -valine in stead of glutamic acid

Question 37

Which proteins sometimes aid the folding process?

Answer 37

chaperones

Question 38

What is prion disease an example of?

Answer 38

folding polypeptide disease

Question 39

What does haemoglobin consist of?

Answer 39

four subunits two alpha and two beta chains each contains a haem group