Population Ecology Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What does genetic equilibrium mean in regards to allele frequencies?

A

There are no changes in allele frequencies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is the population changing/evolving under genetic equilibrium?

A

No.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is another name for genetic equilbrium?

A

Hardy-Weinberg Equilibrium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Can evolution occur at genetic equlibrium?

A

No.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is microevolution in regards to allele frequencies?

A

Gradual change in allele frequencies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do mutations do to the DNA of an individual?

A

Change them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens if the number of back mutations is the same as the number of mutations?

A

There are no net mutations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are back mutations?

A

They reverse the effects of former mutations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What type of mutations can diversify the gene pool?

A

Heritable mutations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is gene flow the net movement of? How does it happen?

A

It is the net movement of alleles from one population to another due to migration of individuals?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Does gene flow increase or decrease the genetic diversity in one population? How about between populations?

A

Gene flow increases the genetic diversity in one population and reduces the genetic diversity between populations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Is random mating common? Why or why not? (2)

A

Random mating is uncommon due to the preferred phenotypes and inbreeding.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is an example of inbreeding?

A

Some flowers will self-pollinate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the change in allele frequences due to CHANCE events called?

A

genetic drift

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What will happen to unique alleles if particular individuals with them do not breed?

A

The alleles may be lost from the gene pool.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Is natural selection a form of genetic drift? Why or why not?

A

It is not a form of genetic drift since it is not random at all.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Name two examples of genetic drifts. (2)

A

The founder effect and the bottleneck effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are individuals who form new populations called?

A

Founders.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What type of alleles may increase because of the founder effect?

A

Rare alleles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Do founders represent the gene pool? Why or why not?

A

They do not usually represent the gene pool since they are usually a small group of individuals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Is the founder effect a gene pool change?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the bottleneck effect?

A

Gene pool change that results from rapid decrease in the population size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Does the bottle neck effect reduce or increase genetic diversity?

A

Reduce.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What process leads to evolutionary adaptation?

A

Natural selection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does a gene do?

A

A gene codes for a particular trait carried on chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the heterozygote advantage? Name an example.

A

When a harmful/lethal allele is actually beneficial in its heterozygous form. Sickle cell anemia-heterozygous form gives malaria resistance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is an allele?

A

A form of a gene.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a gene pool a sum of?

A

It is a sum of all the alleles for all genes in a population.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a genotype frequency?

A

A proportion of the population with that specific genotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Is the more variety in a gene pool beneficial?

A

Yes, it increases chances of survival.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the phenotype frequency?

A

The proportion of a population with a particular phenotype.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is an allele frequency?

A

The rate of occurrence of a particular allele in a population.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Are recessive alleles always less common than dominant alleles?

A

No.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How do you get genotype freguency? (The mathematical approach)

A

Divide the number of individuals with that genotype by the total number of individuals in that population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Under which conditions will allele frequencies remain the same? (5) What is this called?

A
  1. the population is large enough so that chance events won’t alter allele frequencies.
  2. Mates are chosen randomly.
  3. There are no mutations in the gene that affect phenotype.
  4. There is no migration.
  5. There is no natural selection against any phenotype.
    This is called the Hardy Weinberg Principle
25
Q

What is the Hardy-Weinberg genotype calculation equation?

A

p^2+2pq+q^2=1.00

26
Q

What do p and q represent in the H-W genotype calculation?

A

P= frequency of dominant alleles. Q= frequency of recessive alleles.

27
Q

What does p+q equal?

A

1.00

27
Q

In order for the H-W genotype calculation to be correct, what form do the frequencies of alleles have to be in?

A

Their decimal form.

27
Q

What is population density?

A

The number of organisms in a given area.

28
Q

What are the three population distribution patterns?

A

Uniform, random (no pattern) , clumped (organisms are in groups)

29
Q

Which distribution pattern is most common?

A

Clumped

30
Q

What facts affect distribution strategies? (3)

A

Distribution of resources in a habitat, reproductive strategies (organisms exhibiting asexual repro tend to be clumped), may vary with life stages

30
Q

What four factors can contribute to the size of a population?

A

Number of births, number of deaths, immigration, emigration

31
Q

What is the equation for calculating change in population size?

A

Change in population=(number of births + number of immigrants) - (number of deaths + number of emigrants)

32
Q

What is the equation for calculating the rate of population growth?

A

gr= change in population/change in time

32
Q

What does growth rate not take into account that per capita growth rate does?

A

The initial size of a population.

33
Q

What is the equation for calculating the per capita growth rate?

A

capita growth rate = change in population/ original number of individuals

34
Q

What are the two population growth curves?

A

J-shaped, and s-shaped

35
Q

What type of growth is exhibited in a J-shaped curve? What allows this to occur?

A

Exponential growth which occurs due to unlimited resources.

36
Q

Which population growth curve will reach a carrying capacity?

A

S-shaped

37
Q

What is the growth shown by an s-shaped curve called?

A

Logistic Growth

38
Q

What is the period at the beginning of a population growth curve where growth is slow called?

A

The lag phase.

39
Q

Why does a lag phase exist?

A

Because only a few individuals exist to reproduce.

40
Q

What is the stationary phase?

A

A phase where birth and death rates are equivalent.

41
Q

What is the theoretical maximum population size the environment can sustain over an extended period of time called? What is the variable?

A

Carrying Capacity (K)

42
Q

What is the highest per capita growth rate possible called? What is the variable?

A

Biotic Potential (r)

43
Q

What are two types of factors that limit carrying capacity? Are they generally biotic or abiotic?

A

Density dependent (generally biotic)
Density independent (generally abiotic)

44
Q

What is environmental resistance a combination of?

A

A combination of limiting factors.

45
Q

What prevents a population from growing at its biotic potential and determines carrying capacity?

A

Environmental Resistance

46
Q

What are two types of life strategies?

A

r-selected and K-selected strategies

47
Q

Name some of the r-selected strategies. Name an example. What kind of curve do they typically display?

A

Short life span, early repro age, large broods of offsprings with little to no care. Insects, rabbits, annual plants are some examples. They generally are represented by the J-shaped curve.

48
Q

Name some of the K-selected strategies. Name an example. What kind of curve do they typically display?

A

Fewer offsprings with parental care relatively mature repro age, tend to be larger. Bears and people are examles. Generally represented by S-shaped curves.

49
Q

What life strategy do most populations exhibit?

A

A combination of r and K selected strategies.

50
Q

What can an understanding of life strategies be useful for?

A

Predicting the success of a species in a given environment.

51
Q

What is intraspecific competition?

A

Competition for limited resources among members of the same species.

51
Q

Does interspecific competition or intraspecific competition play a role in natural selection?

A

Intraspecific

52
Q

What are two ways species use to avoid parents out-competing offsprings?

A

Dispersal of young/seed and different life stages in which different resources are used

52
Q

What is the competition between members of different species in the same community called?

A

Interspecific

53
Q

What is a niche?

A

Habitat and role in a community.

54
Q

What are some prey defense mechanisms?

A

Bitter-tasting chemicals, thorns, camouflage, cryptic coloration, mimicry

54
Q

Does competition drain energy?

A

Yes

55
Q

What is a batesian mimicry?

A

A harmful organism mimics a harmful or unpleasant one.

56
Q

What is a mullerian mimicry?

A

Two unpleasant or harmful species resemble one another.

57
Q

What is a symbiotic relationship?

A

A relationship between two organisms living close to one another.

58
Q

What is commensalism?

A

A symbiotic relationship where one partner benefits and the other neither benefits nor is harmed.

58
Q

What is mutualism?

A

A symbiotic relationship where both partner benefit.

59
Q

What is parasitism?

A

One species benefits and the other is harmed.

60
Q

Why do stages in succession happen?

A

Because of interspecific competition.

61
Q

Name the stages in the cycle of succession.

A

Pioneer community, climax community, ecological disturbance

61
Q

Is there soil present in primary succession?

A

No

62
Q

What is a climax community? What is the following stage in the succession?

A

A mature ecosystem. The following stage is ecological disturbances.

62
Q

What are the first species to colonize an area called? What are they capable of doing? Example.

A

Pioneer community, they are capable of breaking down rock. Examples=lichen/moss

63
Q

Are all ecological disturbances bad?

A

No, some are good and healthy for the environment.

64
Q

When does secondary succession take place?

A

After an ecological disturbance.

65
Q

What determines what type of organisms will be in the pioneer community during secondary succession?

A

The size of the disturbance that preceded it.