1.7 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.

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

What does L.U.C.A. stand for?

A

Last universal common ancestor.

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

How do genomic variations arise?

A

Mutations.

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

Why processes does evolution involve?

A

Selection, gene transfer and speciation.

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

What is natural selection?

A

The non-random increase in frequency of DNA sequences that increase survival and the non-random reduction in the frequency of deleterious sequences.

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

Changes in phenotype frequency are as a result of?

A

Stabilising, directional and disruptive selection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
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
8
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
9
Q

What happens in disruptive selection?

A

Two or more phenotypes are selected for.

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

What are the two types of gene transfer?

A

Vertical and horizontal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
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
12
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
13
Q

Why is natural selection more rapid in prokaryotes?

A

They can exchange genetic material horizontally.

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

Does vertical gene transfer happen quickly or slowly?

A

Slowly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
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
16
Q

What is a species?

A

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

17
Q

What is the importance of isolation?

A

For speciation to occur, two subpopulations of the same species must become isolated from each other so that there is no gene done between the subpopulations.

18
Q

What’s the importance of isolation barriers?

A

They prevent gene flow between sub-populations during speciation.

19
Q

What is allopatric speciation?

A

Gene flow is prevented by a geographical barrier.

20
Q

What is sympatric speciation?

A

A form of speciation where two species arise within the same habitat. It occurs as a result of behavioural or ecological barriers.