U1.7 Evolution Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What is evolution?

A

The changes in organisms over generations as a result of genomic variations arising through mutations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is natural selection?

A

The weeding out of individuals of a species with a phenotype less suited to their environment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is natural selection the non-random increase in?

A

Frequency of DNA sequences that increase survival rates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is natural selection the non-random decrease in?

A

The frequency of DNA sequences that decrease survival rates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are changes in phenotype frequency in a population a result of?

A

Stabilising, directional, and disruptive selection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens in stabilising selection?

A

An average phenotype is selected for and extremes of the phenotype range are selected against.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What happens in directional selection?

A

One extreme of the phenotype range is selected for.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens in disruptive selection?

A

Two or more phenotypes phenotypes are selected for.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe natural selection in prokaryotes.

A

It is more rapid. Prokaryotes can exchange genetic material horizontally, resulting in faster evolutionary change than in organisms that only use vertical transfer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is horizontal gene transfer?

A

Where genes are transferred between individuals in the same generation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is vertical gene transfer?

A

Where genes are transferred from parent to offspring as a result of sexual or asexual reproduction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does horizontal gene transfer result in?

A

Rapid evolutionary change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a species?

A

A group of organisms capable of interbreeding to produce fertile offspring, and which does not normally breed with other groups.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is speciation?

A

The generation of new biological species by evolution as a result of isolation, mutation and selection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why are isolation barriers essential?

A

To prevent gene flow between sub-populations during speciation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What causes allopatric speciation?

A

Geographical barriers.

17
Q

What causes sympatric speciation?

A

Behavioural and ecological barriers.