B5.2 Natural Selection And Evolution

Question 1

What is phylogenetics?

Answer 1

The study of evolutionary relationships

Question 2

Give 3 advancements that have improved classification

Answer 2

• Developments in microscopy
• Developments in biochemistry
• New DNA evidence

Question 3

Describe the process of natural selection

Answer 3

• Populations are naturally varied due to random genetic mutations
• Some of these mutations provide a selective advantage
• These organisms survive and reproduce, passing on the successful genes

Question 4

Define evolution

Answer 4

Evolution is a change in the genetic makeup of a population over time due to natural selection

Question 5

Give 2 pieces of evidence for evolution

Answer 5

• Fossils

- Antibiotic resistance

Question 6

Describe how antibiotic resistance arises

Answer 6

• A random genetic mutation causes a bacterium to become resistant to the antibiotic
• When the antibiotic is used, all the bacteria that do not have the mutation are killed
• The population containing just the resistant bacteria then begins to grow

Question 7

Describe how two new species develop from one species

Answer 7

• A population is split where members of the population are isolated
• The environments become different and so natural selection will occur differently
• The two groups will become different enough that they cannot breed to produce fertile offspring anymore

Question 8

Why was Darwin’s theory only slowly accepted?

Answer 8

• Most people still believed God created all the life on earth
• There was insufficient evidence to support his theory

Question 9

Define artificial classification

Answer 9

A system that groups organisms together using observable characteristics. They do not take evolutionary relationships into account.

Question 10

Define natural classification

Answer 10

A system that groups organisms together based on similarities and differences in DNA. Evolutionary links are established.