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Flashcards in Exam 3 Deck (56)
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1
Q

Evolution

A

Change in a population overtime

2
Q

Natural Selection

A

The process by which organisms better adapted to their environment tend to survivie and produce more offspring

3
Q

5 agents of evolutionary change

A
Natural Selection
Genetic Drift
Founder Effect
Bottleneck
Gene Flow
Sexual Selection
4
Q

Genetic Drift

A

A random change in allele frequencies in a population

5
Q

Fixation

A

The reduction of genetic variation due to genetic drift

6
Q

Founder Effect

A

Small number of individuals leave a population and become the founders of a new area - usually having a different allele frequency than the original population

7
Q

Bottleneck

A

Reduction of a population (usually caused by death) leaving a small fraction of the original population intact, this smaller population will usually have different allele frequencies than those that died

8
Q

Gene Flow

A

Migration into or out of a population will change allele frequencies

9
Q

Sexual Selection

A

A form of natural selection that depends on an individuals ability to obtain a mate

10
Q

Fitness

A

A measure of the relative amount of reproduction of an individual with a particular phenotype compared to the reproductive success of an individual with a different phenotype

11
Q

3 important elements to an organisms fitness

A

Environment
Fitness measured relative to other genotypes or phenotypes in the population
Depends on an organisms reproductive success compared to the other organisms in the population

12
Q

Stabilizing Selection

A

Individuals with intermediate phenotypes are most fit

13
Q

Disruptive Selection

A

Individuals with extreme phenotypes experience the highest fitness, and those with intermediate phenotypes have the lowest

14
Q

Species

A

Population that is capable of interbreeding to poduce healthy fertile offspring

15
Q

Reproductive Barriers

A

Prezygotic and Postzygotic barriers

16
Q

Prezygotic Barriers

A

Prevent mating between different species (this happens before the fusion of sperm and egg)

17
Q

Temporal Isolation

A

Mating times differ (some like mornings, some like nights, etc)

18
Q

Habitat Isolation

A

Living in different habitats that dont allow organisms to cross paths easily

19
Q

Behavioral Isolation

A

No sexual attraction (you looking for a buff guy not a bitch like nik)

20
Q

Mechanical Isolation

A

Wrong organs to fuck with (my nigga doesnt have a penis that goes into a vagina)

21
Q

Gametic Isolation

A

Egg and sperm fail to fuse to make zygote

22
Q

Postzygotic Barriers

A

Barriers that occur after the hybrid zygote is formed

23
Q

Hybrid Sterility

A

The hybrid cannot reproduce

24
Q

Mechanisms of Speciation

A

Making a new species

25
Q

Altruistic Behavior

A

Behaviors that come at a cost to the individual doing the behavior while benefiting the recipient (jumping infront of a bullet to save someones life)

26
Q

Female investment to reproduction

A

Produces larger gamete (egg) (by making larger gamete, the female has already invested more towards reproduction because this takes more energy to do)

27
Q

Male investment to reproduction

A

Produces the smaller, usually mobile gamete

28
Q

Tactics for getting a mate

A

Courtship rituals
Gifts
Control resources
Looks

29
Q

Tactics for keeping a mate

A

If the offspring benefit from having a father, the male is more likely to provide parental care

30
Q

Mate Gaurding

A

Copulatory plugs-break off penis into her so no other penis can get in

31
Q

Monogamy

A

One male one female

32
Q

Polygyny

A

1 male bunch of females

33
Q

Polyandry

A

1 female and bunch of males

34
Q

Sexual Dimophism

A

Differences between male and female (size, aggressiveness)

35
Q

Sexual Monomorphism

A

Male and females look the same

36
Q

Ecology Levels

A
Individual
Population
Community
Ecosystems
Biosphere
37
Q

Individual

A

Organism

38
Q

Population

A

A group of individuals of the same species living in a defined area

39
Q

Community

A

Consists of two or more populations of diff species living in the same area

40
Q

Ecosystems

A

Consists of a community of living things interacting with the physical aspects if their environment

41
Q

Biotic Factors

A

Living things in an ecosystem

42
Q

Abiotic Factors

A

Nonliving things in an ecosystem

43
Q

Biosphere

A

Consists of all the earths ecosystems containing living species

44
Q

Limitations for species to live

A

Physical factors
Interactions with other species
Geographical barriers

45
Q

Interactions between species

A
Competition
Predation
Parasitism
Commensalism
Mutualism
46
Q

Competition

A

Two species competing for resources

47
Q

Competitive exclusion

A

When one species wins the competition with another species excluding it

48
Q

Predation

A

Predators seek prey to survive

49
Q

Parasitism

A

One species benefits at the expense of another (without killing it for as long as possible)

50
Q

Commensalism

A

One species benefits but the other is unharmed

51
Q

Mutualism

A

Both benefit from the interaction

52
Q

Genetic Biodiversity

A

The collection of genes within a population

53
Q

Causes of biodiversity loss

A
Habitat destruction
Invasive species
Overharvesting
Pollution
Climate change
54
Q

Population growth

A

Most species cannot handle expionential growth

55
Q

Density dependent

A

Events that depend on a population size to occue

56
Q

Density independent

A

Events that dont depend on the population of a species to occur