Chapter 13: How Populations Evolve Flashcards Preview

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Flashcards in Chapter 13: How Populations Evolve Deck (61)
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1
Q

What is evolution

A

Descent with modification

2
Q

Who is Charles Darwin

A

Famous for proposing that evolution occurs by natural selection and for writing “origin of species”

3
Q

How did Darwin study evolution

A

Compared how their appearance, mating and eating habitats change with different locations and climate (water vs land) (cold vs warm) (wooded area vs beach)

4
Q

What did Darwin observe

A

Blue footed booby, marine iguana, giant tortoise, finches

5
Q

Who studies evolution

A

Paleontologist

6
Q

Paleontologist

A

Study fossils, imprints of remains of organisms that lived in the past

7
Q

Amber

A

Fossilized resin produced by pine trees

8
Q

Ammonite cast

A

Replicas of ammoites which were shelled marine animals related to the present day nautilus

9
Q

Fossils found in the ______ layer are older than those found in ______ layere

A

Lower, upper

10
Q

Carbon dating

A

Estimates fossils age up to 50,000 years old

11
Q

The longer the organism has been dead….

A

Less carbon and more nitrogen tend to be present in body

12
Q

How does carbon dating work

A

Compares amount of carbon 14 in the air to the amount of c in the fossil (dead organism)

13
Q

Homologous structures

A

Have different functions but are structurally similar because of common ancestry.

14
Q

Veterbrae

A

Organism that Has backbone

15
Q

Analogous structure

A

Have similar appearance and functions but they aren’t derived from a common ancestor (evolved independently)

16
Q

Example of analogous structures

A

Wings of a bird and butterflies (which are insects) have the same function flying but they evolve separately

17
Q

Biogeography

A

Compares organism and their traits between different locations geographies

18
Q

Marsupials

A

Animals which carry their young in a pouch

19
Q

Comparative anatomy

A

Compares body structures between organism

20
Q

Molecular biology

A

Compares DNA sequences between different organism

21
Q

What does each branch point represent in a evolutionary tree

A

Common ancestor of the lineages beginning there and to the right of it

22
Q

A hatch mark represents what in a evolution tree

A

Homologous character shared by all the groups to the right of the mark

23
Q

Ostriches, hawks, and others are considers what

A

Birds

24
Q

Lizards, snakes and crocodiles are considered what

A

Reptiles

25
Q

What are tetrapods

A

4 appendage

26
Q

What is an evolutionary tree

A

Allows us to determine which traits are shared by different organisms and which ones are unique to a certain group of organisms

27
Q

Tetrapods limbs are shared by…

A

Amphibians, mammals, reptiles, and birds but not lungfishes

28
Q

Amnion

A

Fluid filled membrane that encloses an embryo is shared by mammals, reptiles, and birds but not by lungfishes and amphibians

29
Q

What are unique to birds

A

Feathers

30
Q

How does nature affects evolution

A

Natural selection

31
Q

Natural selection

A

The process where nature selects traits that help organism survive and reproduce in a specific environment and over time increase in population

32
Q

Example of natural selection

A

The surviving and increase of the bugs resistant to pesticides rather than the bug that is not.

33
Q

3 rules of evolution by natural selection

A

1) populations evolve, not individuals
2) natural selection can only affect heritable (encoded in DNA) traits (not acquired traits
3) perfectly adapted organism are not created by natural selection

34
Q

What forces affect evolution

A

Artificial selection

35
Q

Artificial selection

A

Process by which humans select and breed organism with desired traits

36
Q

What are the sources of variation within a population

A

Mutation and sexual reproduction

37
Q

Mutation

A

Change in the nucleotide sequence of DNA and ultimate source of new alleles

38
Q

The hardy-Weinberg equilibrium

A

Used to calculate the allele and genotype frequencies in population

39
Q

What is the equation for hardy-Weinberg, us to calculate frequency or genotypes

A

P2 + 2pq + q2 = 1, P + q = 1

40
Q

P represent in hardy Weinberg equation

A

Frequency of dominant allele

41
Q

To be in a hardy weinberg equilibrium a population must

A
Be very large
Keep all its members together, keep strangers away
Not mutate
Have random mating (no inbreeding)
Not undergo natural selection
42
Q

How do you find the frequency of a dominant phenotype

A

P2 + 2pq

43
Q

Determines frequency of recessive phenotype

A

Q2

44
Q

How can the gene pool of a population change

A

Natural selection, genetic drift, gene flow

45
Q

What is an example of adaptive evolution

A

Natural selection

46
Q

Natural selection

A

Alleles selected by nature, they are favorable for survival and reproduction of a population

47
Q

What are examples of non-adaptive evolution

A

Genetic drift and gene flow

48
Q

Genetic drift

A

A random change in allele freq; bottlenecking effect. Alleles are randomly selected; may be favorable for survival

49
Q

Gene flow

A

When genes or alleles move in and out of population because of changes in mating locations

50
Q

Bottlenecking effect

A

Lead to loss of genetic diversity when population is greatly reduced in size because sudden change in environment.

51
Q

Examples of bottlenecking

A

Fire, earthquake, flood

52
Q

Founder effect

A

Leads to loss of genetic diversity when a few individuals isolated from a large population creating new population(s)

53
Q

What are the different effects of natural selection

A

Stabilizing selection, directional selection and disruptive selection

54
Q

Disruptive selection

A

favors individual at both ends with phenotypic range allowing mice with light or dark fur colors to survive

55
Q

Stabilizing selection

A

Favors individuals with intermediate fur colors selecting against individuals with light and dark fur colors

56
Q

Directional selection

A

Acts against individuals at one end of phenotypic range

57
Q

Sexual selection

A

Type of natural selection where members of the same species compete for access to mates

58
Q

Primary structures

A

Are needed for reproduction to happen (viable sperm and penis)

59
Q

Secondary sex structures

A

Are not involved into reproduction directly but the chance of reproduction occurring (ex; feathers of male peacocks)

60
Q

Balancing selection

A

Occurs when natural selection maintains stable frequencies of two or more phenotypic forms in a population

61
Q

Frequency dependent selection

A

Is a type of balancing selection that maintains two different phenotypic forms in a population acting against either form when becomes too common in a population