Natural Selection & Evolution

Question 1

Define: Evolution

Answer 1

Changes in the heritable characteristic of organisms over generations

Question 2

Define: Natural selection

Answer 2

The process by which organisms that are better adapted to their environment survive, reproduce and pass on their advantageous alleles, causing advantageous characteristics to increase in frequency within a population

Question 3

What is Lamarckism?

Answer 3

The idea that an organism could pass on physical characteristics they acquired during their lifetime to their offspring (For example, if you lift weights, then the extra muscle mass would be passed on to your offspring)

Question 4

What is the definition of selection pressure

Answer 4

An external factor that influences the reproductive success of an individual

Question 5

Fill in the blank.

Natural selection can only take place when there is ________ __ _ _________

Answer 5

Variation in a population

Question 6

Variation results from small differences in DNA base sequences between individual organisms within a population.

What are the sources of these differences in DNA base sequences?

Answer 6

• mutation
• meiosis
• Random fertilization during sexual reproduction

Question 7

What does overproduction of offspring within a population lead to?

Answer 7

Competition for resources

Question 8

What does carrying capacity mean?

Answer 8

The maximum population size of a species that can be sustained by the resources available in that specific environment

Question 9

What would an insufficient amount of resources lead to?

Answer 9

A large number of offspring would fail to survive and reproduce

Question 10

Fill in the blank.

Overproduction of offspring and completion for resources promote _______ _________

Answer 10

Natural selection

Question 11

What is interspecific competition?

Answer 11

Competition between individual of different species

Question 12

What is intraspecific competition?

Answer 12

Competition between individuals of the same species

Question 13

Which plays a greater role in evolution?
Interspecific completion or intraspecific competition?

Answer 13

Intraspecific

(because individuals are more likely to interact with members of their own species. Individuals of the same species share the same niche and they are affected by the same abiotic and biotic factors.)

Question 14

List 7 abiotic factors

Answer 14

1. Light intensity (Plants for photosynthesis)
2. Temperature (Rate of photosynthesis)
3. Moisture levels (Plants and animals require water to survive)
4. Soil pH and mineral content (different species of plants are adapted to different soil pH levels and nutrient concentration levels)
5. Wind direction and intensity (Wind speed affects transpiration rate in plants)
6. Carbon dioxide levels (for plants. Required for photosynthesis)
7. Oxygen levels for aquatic animals (Some aquatic animals can only survive in water with high oxygen concentration)

Question 15

What is sexual selection?

Answer 15

A form of selection pressure that occurs due to the preference of one sex for certain characteristic in individuals of the other sex

Question 16

What is sexual dimorphism?

Answer 16

The distinct difference in size and appearance between the sexes of an animal species. (Commonly seen in birds of paradise where the male birds are brightly computed and perform intricate courtship displays)