D.3 - Agents of Evolution

Question 1

Mechanisms of evolution

Answer 1

Natural/ Established process by which evolution takes place

1. Genetic Drift - Founder and Bottleneck Effect
2. Gene Flow
3. Non-random mating
4. Mutations
5. Natural Selection - Directional, Stabilizing, Disruptive (all graphs), Sexual (not a graph)

Question 2

Directional selection

Answer 2

A single extreme phenotype is favoured, causing allele frequency to shift in 1 direction

Question 3

Stabilizing Selection

Answer 3

Favours average phenotype, selecting AGAINST extreme phenotypes

Question 4

Disruptive Selection

Answer 4

BOTH extreme phenotypes are favoured over average ones

Question 5

Bimodal Distribution

Answer 5

Organisms exist with either 1 or 2 features, as opposed to a single range of characteristics

Question 6

Selective Breeding

Answer 6

Selecting mates for breeding purposes based on desired phenotypes

Question 7

Accidental Selection

Answer 7

the process of evolution of a particular group in a species due to circumstances like a natural disaster

Question 8

Industrial Melanism

Answer 8

Evolutionary change of predominant COLOUR of organism due to environmental impact (i.e. pollution) of industrial revolution (peppered moth)

Question 9

Biological Magnification

Answer 9

Toxins that accumulate in tissues of prey continue to get accumulated in tissues of predator (because they eat infected prey)

Question 10

Gene Mutations

Answer 10

Change in sequence of DNA, which occurs during replication

Question 11

Mutagens

Answer 11

Chemical substance or type of radiation that can cause a disruption to normal processes of DNA replication

Question 12

Genetic Drift

Answer 12

Random changes to gene frequences in gene pool of population/ species

Question 13

Bottleneck Effect

Answer 13

Population declines to low number (due to environmental disaster, overhunting, etc) then rebounds. Original decrease in gene pool results in decreased genetic diversity.

Question 14

Gene Flow

Answer 14

Change in gene frequencies of population caused by introduction of phenotypes from another population (occurs when members of 1st pop inbreed with members of 2nd pop)

Question 15

Immigration

Answer 15

Entering a popualtion

Question 16

Emigration

Answer 16

Exiting a population

Question 17

Genetic Distance

Answer 17

Measure of how closely organisms are related genetically. More similar the genomes, more related they are.

Question 18

Founder Effect

Answer 18

Small sample of population is seperated from rest of population resulting in decreased diversity.

Question 19

Non-random Mating

Answer 19

Occurs when probability of two individuals in a population mating, is not the same for all possible pairs.

Question 20

Inbreeding

Answer 20

Individuals are more likely to mate with close relatives than with distant relatives.

Question 21

Sexual Selection

Answer 21

Male or female gains unique desired characteristics (mates chosen on presumption that the better the outward appearance, the stronger the genetics)