Learning Guide 18

Question 0

What is the relationship between a population and a species?

Answer 0

A group of individuals of a species live in a population

Question 1

What is the definition of a population?

Answer 1

A group of individuals of a species that live in a particular area

Question 2

What are four variables that govern changes in population size?

Answer 2

Births, deaths, immigration, emigration

Question 3

What are factors that affect the size of a population?

Answer 3

Biotic potential and environmental resistance

Question 4

What is biotic potential?

Answer 4

Factors that favor increase in population size

Question 5

What is environmental resistance?

Answer 5

Factors that favor decrease in population size

Question 6

What is carrying capacity?

Answer 6

The maximum size of a population that a particular environment will support

Question 7

What are the two main types of growth exhibited by populations?

Answer 7

Logistic growth and exponential growth

Question 8

Are there always limits to population growth in nature?

Answer 8

Yes

Question 9

Is carrying capacity the same for all populations and all environments?

Answer 9

No

Question 10

Describe Type I survivorship curve.

Answer 10

• Little mortality in the early part of the lifespan
• Majority of individuals survive to reach reproductive age
• Greatest amount of mortality occurs in later portion of lifespan

Question 11

Give examples of organisms that exhibit Type I survivorship curve.

Answer 11

Humans, elephants, polar bears

Question 12

Describe Type II survivorship curve.

Answer 12

The probability of dying is the same at any time during organism’s lifespan

Question 13

Describe Type III survivorship curve.

Answer 13

Majority of mortality in the early part of the potential lifespan, small percentage of initial number of individuals survive to reproductive age

Question 14

Examples of organisms that exhibit Type III survivorship curve

Answer 14

Insects, annual plants, oysters

Question 15

What phrase did Darwin use originally instead of the term evolution?

Answer 15

descent with modification

Question 16

Name the three key observations that support Darwin’s theory of evolution.

Answer 16

All species produce more offspring than the environment can support, individuals of a population vary in their traits, organisms’ variations can be inherited by their offspring

Question 17

What is the mechanism for evolution?

Answer 17

Natural selection

Question 18

What is natural selection?

Answer 18

Differential or unequal success and reproduction

Question 19

What is artificial selection?

Answer 19

The opposite of natural selection, humans select desired characteristics

Question 20

What is the smallest unit that can evolve?

Answer 20

Population

Question 21

What is Hardy-Weinberg equilibrium?

Answer 21

No change in frequencies of alleles in gene pool, no microevolution

Question 22

What is microevolution?

Answer 22

Change in the gene pool, studied by looking at frequencies of alleles

Question 23

What five conditions are necessary for Hardy-Weinberg equilibrium to be maintained?

Answer 23

Population is very large, population is very isolated, gene mutations cannot occur, mating is random, all individuals are equal in reproductive success.

Question 24

What are the five causes of microevolution?

Answer 24

Genetic drift, genetic flow, mutation, nonrandom meeting, natural selection