B13

Question 1

What is Evolution

Answer 1

Evolution is the change in the inherited characteristics of a population over time through a process of natural selection which may result in the formation of a new species.

Question 2

What is the most widely accepted theory of evolution?

Answer 2

The theory of natural selection

Question 3

Describe the theory of natural selection

Answer 3

1. In a species all the individuals are different and show a wide range of variation
2. This variation is because of differences in their genes (continuous mutations).
3. Individuals with characteristics most suited to the environment (have an advantage)
   are more likely to survive and reproduce
4. The genes/alleles that allow these individuals to be successful (have an advantage)
   are passed to their offspring.

Question 4

Why did people not believe Darwin?

Answer 4

⚫ His theory challenged the idea that God made all living things on earth.
⚫ There was insufficient evidence at the time the theory was published to convince
Scientists at the time.
⚫ The mechanism of inheritance/genes was not known until 50 years after his theory
was published.

Question 5

What is selective breeding?

Answer 5

Selective breeding is the process by which humans breed plants and animals for particular genetic characteristics.

Question 6

Steps of selective breeding

Answer 6

1. Decide which characteristics are important (desirable characteristics) e.g. large muscle mass or blue flowers.
2. Choose parents that show these characteristics
3. Breed the two parents together.
4. Select the offspring that have the desired characteristics to breed the next generation.
5. Repeat the process continuously (over a number of years) until all of the organisms have the desired characteristic.

Question 7

Advantages of selective breeding

Answer 7

Can produce animals and plants with desired characteristics

Increased milk/meat yield from cattle

Can produce domesticated animals

Question 8

Disadvantages of selective breeding

Answer 8

Plants and animals may become more susceptible

More likely to suffer from genetic conditions

Question 9

What is genetic engineering?

Answer 9

Processing of modifying an organisms genome

Question 10

Stages of genetic engineering

Answer 10

Select
Isolate
Insert
Reproduce

Question 11

Advantages of genetic engineering

Answer 11

Fruit/veg have a lomger shelf life

Pest resistant

Question 12

Disadvantages of genetic engineering

Answer 12

Damage to food chains

Can be harmful if consumed