Unit 7 Natural Selection (AP Bio)

H-W Equilibrium

100

The variables q² , q, P², and P stand for...

Homozygous recessive, recessive allele, Homozygous Dominant, dominant allele 

200

In a population of 100 birds, 30 of these birds have short wings, which is recessive. What is the frequency of q²

.3

300

A population of 200 individuals has 20 individuals who show a recessive trait. What is the frequency of the recessive allele? 

.316

400

A population of 500 individuals has 250 that show a recessive trait. What is the frequency of heterozygous individuals? 

.42

500

Hardy-Weinberg relies on five key principles to maintain equilibrium and reflect that no evolution is occurring. List three of these principles. 

1. No Natural Selection

2. No mutations 

3. No Genetic Drift

4. Large Sample Size

5. Random Mating 

Natural Selection

100

Concept defined as "struggle for existence" 

Competition 

200

Define a "niche."

A role within an ecosystem 

300

Define fitness 

how well an organism fits that niche 

400

If there is an open niche within an environment...

An organism will adapt to fill that niche 

500

Define Directional Selection 

There is favoritism for one particular phenotype (Long necks in giraffes) 

Speciation

100

Allopatric Speciation 

geographic separation causes reproductive isolation

200

Sympatric Speciation 

species live in the same area but are reproductively isolated for another reason

300

List three examples of Pre-zygotic Barriers 

1. Temporal Isolation

2. Behavioral Isolation

3. Geographic Isolation

4. Mechanical Isolation 

5. Ecological Isolation

6. Gametic Isolation 

400

Requirements for a species to exist 

1. Must be fertile 

2. Remains viable into adulthood 

3. Cannot mate with other species 

500

List Post-Zygotic Barriers 

Reduced Hybrid Viability, fertility, and hybrid breakdown 

Population Genetics

100

In a population of 100 beetles, 10 beetles leave to start their own population. What phenomena has occured?

Founder Effect 

200

In Clovis, NM, there is a large population of lizards. A drought occurs, causing much of the population to die off. What phenomena has occured? 

Bottleneck effect

300

Why is variation important in a population?

It increases the likelihood that some members of the population will survive environmental change, disease, etc.

400

List three methods of decreasing genetic variation

1. Non-Random Mating

2. Genetic Drift

3. Natural Selection

500

List the three methods of increasing genetic variation in a population

1. Mutations

2. Gene Flow

3. Sexual Reproduction 

Vocab Practice

100

Artificial Selection 

Humans choose particular traits to be passed on

200

Genetic Drift 

Organisms moving in and out of the gene pool

300

Founder Effect 

A portion of the original population leaves to start a new population 

400

Bottleneck Effect 

A disaster occurs, causing a major loss in a population

500

Temporal Isolation 

species breed at different times and therefore not with each other