Unit 1-Evolution

Question 1

Changes in organisms over generations as a result of genomic variations.

Answer 1

Evolution

Question 2

Exchange of genetic material

Answer 2

Gene transfer

Question 3

When genes are transferred down generations (from parents to offspring via sexual or asexual reproduction)

Answer 3

Vertical gene transfer

Question 4

When genes are transferred across from an individual to others in the same generation

Answer 4

Horizontal gene transfer

Question 5

Genes transferred from parent to offspring as a result of sexual or asexual reproduction

Answer 5

Vertical gene transfer

Question 6

Prokaryotes such as bacteria can exchange genetic information through this type of gene transfer

Answer 6

Horizontal gene transfer.

Question 7

Non-random increase in frequency of DNA sequences that increase survival

Answer 7

Natural selection

Question 8

Non-random increase in frequency of DNA sequences that increase the reproductive success of the species

Answer 8

Sexual selection

Question 9

This type of selection favours the middle characteristics in a range of variation

Answer 9

Stabilising selection

Question 10

Favours an extreme characteristic away from the middle.

Answer 10

Directional selection

Question 11

Favours two extreme characteristics at the expense of the middle.

Answer 11

Disruptive selection

Question 12

Gene frequency changes by mutation but the effect on the phenotype is minor and gives no change or selective advantage.

Answer 12

Neutral mutation

Question 13

Caused by a phenotype which increases the chances of survival

Answer 13

Selective advantage

Question 14

A group of organisms that can interbreed and produce fertile offspring

Answer 14

Species

Question 15

The formation of a new biological species

Answer 15

Speciation

Question 16

Speciation is a result of

Answer 16

1. Isolation
2. Mutation
3. Selection

Question 17

New species arise due to isolation of a population by geographical barriers.

Answer 17

Allopatric speciation

Question 18

New species arise despite occupying the same geographical area.

Answer 18

Sympatric speciation

Question 19

Examples of geographical barriers

Answer 19

Features such as rivers or mountain ranges

Question 20

Ecological barriers

Answer 20

Isolated by occupying different habitats or breeding areas, pH and salinity

Question 21

Behavioural barriers

Answer 21

Different timings, locations or mating dances may result in members of a population, not being able to mate with each other.