Topic 3 -4

Question 1

What is evolution by natural selection?

Answer 1

Living things vary, and those better adapted to their environment tend to survive and reproduce, passing on advantageous characteristics

These characteristics are said to be selected for.

Question 2

What causes genetic diversity in a population?

Answer 2

A variety of alleles caused by mutations

This diversity is essential for natural selection to occur.

Question 3

What happens to the reproductive efficiency of some individuals during environmental changes?

Answer 3

Natural selection reduces their reproductive efficiency

This can lead to some individuals passing on more alleles to the next generation.

Question 4

What is a niche in ecology?

Answer 4

The ‘role’ of the organism in the community

Organisms have evolved adaptations to occupy their specific niches.

Question 5

Give an example of a niche.

Answer 5

The sea anemone Anthopleura elegantissima in a food web on rocky shores

It feeds on small animals at high tide and remains stationary at low tide.

Question 6

What are adaptations?

Answer 6

Changes that make organisms suited to a new environment

Adaptations can be anatomical, behavioral, or physiological.

Question 7

What is an anatomical adaptation? Provide an example.

Answer 7

A physical (or structural) adaptation, such as the spines of a cactus

These adaptations help organisms survive in their environments.

Question 8

What is a behavioral adaptation? Provide an example.

Answer 8

A change in what an organism does, such as the sun-basking behavior of marine iguanas in the Galapagos

This behavior helps them regulate their body temperature.

Question 9

What is a physiological adaptation? Provide an example.

Answer 9

A change in internal functioning, such as the increased carrying capacity of hemoglobin in people who live at high altitude

This adaptation allows for better oxygen transport in low-oxygen environments.

Question 10

Fill in the blank: The frequency of advantageous alleles in a population increases over ______.

Answer 10

many generations

This process leads to adaptation in the population.

Question 11

True or False: Natural selection can lead to a complete failure to reproduce.

Answer 11

False

Often, it results in a reduction in reproductive success rather than a complete failure.