Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

biol 142 > speciation > Flashcards

speciation Flashcards

1
Q

speciation

A

formation of new species

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

speciation can occur when members of a species no longer

A

reproduce with each other

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

lack of gene flow allows species to

A

become different

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

biological species concept

A

population that can naturally reproduce to produce FERTILE offspring

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

according to biological species concept, species share

A

a single large gene pool

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

limitations to biological species concept

A

-difficult to determine gene flow
-does not work for asexual organisms

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

morphological species concept separates species by

A

body shape and structure

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

enological species concept separates species by

A

how they interact with their environment

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

ecological species concept emphasized … of each species

A

living requirements

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

_____ _____ is required to form truly distinct biological species

A

reproductive isolation

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

to form distinct species, enough differences must develop so that species can no longer

A

breed with each other

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

two forms of reproductive barriers

A

-prezygotic barriers
-postzygotic barriers

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

prezygotic barriers

A

prevents species form successfully attempting to reproduce

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

habitat isolation (prezygotic barrier)

A

species are never in same place

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

behavioral isolation (prezygotic barrier)

A

methods of attracting a mate are different

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

temporal isolation (prezygotic barrier)

A

reproduce at different times

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

mechanical isoltion (prezygotic barrier)

A

reproductive organs are not compatible

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

gene isolation (prezygotic barrier)

A

proteins on egg and sperm don’t match

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

post zygotic barriers

A

prevent growth in a viable fertile adult

20
Q

hybrid

A

offspring of two Dif species

21
Q

hybrid inviablility (postzygotic barrier)

A

embryo cannot complete development because genetic instructions are incomplete

22
Q

hybrid sterility (postzygotic barrier)

A

hybrid cannot produce gametes (sometimes due to odd number of chromosomes)

23
Q

hybrid reduced offspring viability (postzygotic barrier)

A

offspring of hybrids do not survive well

24
Q

3 steps needed for speciation

A

 Isolation of populations of species
 Changes in gene pools of the isolated species
 Creation of reproductive isolation between populations

25
Q

allopatric speciation

A

physical barrier or distance blocks gene flow between 2 populations (physically isolated from each other)

26
Q

sympatric speciation

A

occurs in SAME location
-nonphysical reproduction isolation prevents gene flow

27
Q

examples of sympatric speciation barriers

A

-reproduce at Dif times
-live in Dif parts of environment
-sudden genetic change in 1 population

28
Q

polyploidy

A

doubling number of chromosomes

29
Q

example of sympatric speciation in maggot flies

A

 Several populations live in same area
 Some live on apple trees, some live on hawthorn shrubs
 Flies mate when plant produces fruit
 Hawthorn and apple trees produce fruit 1 month apart
 Very little genetic flow between hawthorn and apple flies since they don’t mate at the same time
 Apple and hawthorn populations different strongly in the frequency of some alleles

30
Q

polyploidy results from mistakes when

A

cells divide

31
Q

polyploidy occurs mostly in

A

plants (can evolve fast by doubling genetic material)

32
Q

polyploidy instantly results in

A

a new species

33
Q

can new species resulting from polyploidy reproduce with original species?

A

NO, new species have different # of chromosomes

34
Q

polyploidy can enable ____ plants to reproduce:

A

hybrid; Doubling the number of chromosomes fixes the problem of having an odd number of chromosomes

35
Q

autopolyploid has more than …

A

2 sets of chromosomes from same species

36
Q

how does autopolyploidy occur?

A

meiosis error can create diploid gametes and combination of 2n gametes produces 4n offspring

37
Q

allopolyploid

A

hybrid between species

38
Q

how can hybrid infertility be overcome?

A

double number of chromosomes again OR hybridize again with parent species

39
Q

adaptive radiation is a mixture of

A

allopatric and sympatric speciation

40
Q

hybrid zones help us tell that ___ occurred

A

speciation

41
Q

what is a hybrid zone?

A

area where members of different species mate

42
Q

hybrid zones: observed patterns

A

reinforcement, fusion and stability

43
Q

reinforcement (hybrid zones)

A

strengthens or reinforces barriers to hybridization

44
Q

example of reinforcement in hybrid zones

A

male species looks different from male of other species in only that area so that females can tell them apart

45
Q

fusion (hybrid zones)

A

weakens barriers to hybridization (increases gene flow)

46
Q

what might reverse speciation and result in 1 species again?

A

fusion

47
Q

stability (hybrid zone)

A

-hybridization remains possible
-hybrids continue to be produced

biol 142 (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions