Cellular and molecular LF130

Question 1

Why does Glucose form an equilibrium of Alpha and beta glucose in solution

Answer 1

Breaks into a linear form where the OH and H groups on the terminal can freely rotate and then reattach to form a circular structure.

Question 2

Energy value of Fatty acids compared to glucose

Answer 2

Twice the energy value of glucose

Question 3

What is the name of the central carbon in an amino acid

Answer 3

‘Alpha carbon’

Question 4

Which direction are proteins read

Answer 4

N terminus to C terminus.

Question 5

Structure and bonding in a generic nucleotide

Answer 5

Phosphate group bonded to a sugar via phosphodiester bond, sugar bonded to base via glycosidic bond.

Question 6

Who drew the kingdom of animals in binomial classification and when

Answer 6

Carolus Linnaeus, 1735

Question 7

Who proposed the theory that different species come from previously extinct species and when

Answer 7

Charles darwin, 1837

Question 8

Who said ‘evolution is a change in allele frequency in a gene pool’

Answer 8

Theodosius Dobzhansky

Question 9

Which three things can be used to examine the lineage of a species

Answer 9

Behavioural and ecological information,
Molecular information
Morphological information

Question 10

Definition of Homologous traits

Answer 10

A similarity between traits because of shared ancestry. These traits are called derived traits

Question 11

Definition of apoptosis and an example

Answer 11

Separation to create separate digits e.g. a hand on a human undergoes apoptosis whereas a Fin on a whale does not.

Question 12

Definition of a synapomorphy

Answer 12

an apomorphy which is shared by more than one taxa.

Question 13

Definition of a clade in a cladistic tree

Answer 13

A node (ancestor) and all of its derived forms

Question 14

Definition of an Autapomorphy

Answer 14

A self derived characteristic: a derived trait that is unique to a given taxon

Question 15

Who deduced that there was a common ancestor, and when? Who revised this idea?

Answer 15

Carl Woese and George Fox in 1977, revision by W Ford Doolittle in 2000.

Question 16

Definition of microevolution (and the 3 main mechanisms by which it occurs) and macroevolution

Answer 16

Microevolution: Change in allele frequencies in a population of a species

(Natural selection, genetic drift, Gene flow)

Macroevolution: Change at or above the level of the species.

Question 17

What was Darwin’s hypothesis in ‘the origin of the species’

Answer 17

• For any particulate trait, individuals within a species are variable
• At least some of this variation is heritable
• Reproduction is not random, but is selected by nature: individuals that reproduce are those with the most favourable variations (survival of the fittest)

Question 18

Describe how genetic drift can be modelled via sampling error

Answer 18

In reality, not every sperm / ova is used in fertilisation. Therefore only a sample of sperm / ova are successful, therefore there is room for sampling error e.g. 50% of a population of sperm have gene A however when sampled, only 20% in the sample have gene A (random chance)

Question 19

Definition of gene flow

Answer 19

Movement of alleles between previously separate populations of the same species.

Question 20

Name of an enzyme lacking a cofactor

Answer 20

Apoenzyme

Question 21

Name of the complex between an apoenzyme and a cofactor

Answer 21

Holoenzyme

Question 22

What is the symbol for catalytic constant

Answer 22

Kcat

Question 23

What is the definition of Kcat

Answer 23

The number of molecules of substrate that one enzyme active site can turn into product per second.

E.g. for carbonic anhydrase, Kcat = 1,000,000s^-1

Question 24

Conditions that alter catalytic consgtants

Answer 24

pH, Temperature.

Question 25

Classes of enzymes and their functions, along with thie EC (enzyme commission number)

Answer 25

EC1: Oxidoreductases
Oxidation/reduction

EC2: Transferases
Transfer of a functional group from one substance to another

EC3: Hydrolases
Formation of two products from a substrate by hydrolysis

EC4: Lyases
Non-hydrolytic addition or removal of groups from substrates

EC5: isomerases
intramolecular rearrangement (isomerisation) e.g. triose-phosphate isomerase

EC6: ligases
ATP-Dependent joining of two molecules by synthesis of new bonds.

Question 26

Who created the ‘lock and key’ model for enzyme function

Answer 26

Emil fischer, 1890s

Question 27

Who produced the ‘induced fit’ model and when, and what is the induced fit model.

Answer 27

in 1958, Daniel koshland Jr. proposed that substrates cause a change in the 3-D relationship of the active site and these changed bring the catalytic groups into the proper orientation for reaction.