ch 16-17

Question 0

why does genetic drift affect small populations more than large

Answer 0

larger variety of genes- genetic diversity increases

Question 1

what factors can lead to evolution besides natural selection?

Answer 1

spontaneous mutations (change allele frequency)

genetic drift (change events after allele frequency-anything in nature-finches and cheetahs)

migration (gene flow-genes from lion to other group)

Question 2

what are the assumptions of the hardy-Weinberg principle

Answer 2

evolution doesn’t change (genetic equilibrium)

Question 3

what are the 2 equations used in the hardy-Weinberg principle

Answer 3

p+q=p^2+2pq+q^2=1

Question 4

what is speciation

Answer 4

process by which species are formed

there has to be reproductive isolation

Question 5

Describe the 3 types of isolation that can lead to speciation

Answer 5

Behavioral Isolation - Courtship rituals keep from interbreeding

Geographic Isolation - separated by physical barrier

Temporal Isolation - reproducing at different times

Question 6

distinguish between adaptive and convergent evolution

Answer 6

adaptive- a single divides into many different types

convergent- 2 diff. objects look similar because of environment (shark and dolphin)

Question 7

what is coevolution

Answer 7

when one organism evolves in response to another (predator, prey evolution) Ex: flowers and their pollenators

Question 8

distinguish between gradualism and punctuated equilibrium

Answer 8

gradualism – when species evolve over time

punctuated equilibrium – only evolve when there are environmental changes

Question 9

describe how molecular clocks can be used to measure how much time has passed sense organisms shared a common ancestor

Answer 9

they use mutation rates in DNA sequences to estimate the time that two species have been evolving independently

they can tell by silent mutations and comparing common ancestors

Question 10

where do all the genes come from

Answer 10

copying genes that can occur due to unequal swapping of DNA during crossing over

modifications in existing genes

Question 11

how can the hox genes lead to evolution

Answer 11

they determine which parts of the body develop and size

A change in them can result in changes in adult animals

Question 12

describe Darwin’s job as a ship naturalist on the HMS Beagle

Answer 12

he documented organisms encountered on each stop

Question 13

List the 3 types of natural selection and define them.

Answer 13

• Stabilizing Selection: environment chooses intermediate forms of a trait
• Directional Selection: environment chooses one extreme form of a trait
• Disruptive Selection: environment chooses both forms of a trait

Question 14

what book did Darwin write

Answer 14

origin of species

Question 15

what two theories did he describe in his book

Answer 15

– Natural selection

– Descent with modifications

Question 16

List the 3 types of natural selection and what their graphs look like.

Answer 16

stabilizing – population after really tall

directional – camel humps

disruptive – original population medium, population after selection camel humps

Question 17

what did Darwin conclude about the finches on Galapagos Islands

Answer 17

they ate something different on each island which affected the beak size

small and short – nuts
small and pointy – insects

Question 18

explain the term “survival of the fittest”

Answer 18

Survival of the fittest is the members of a species with beneficial traits thriving in an ecosystem and those with undesired traits dying off

Question 19

What are the 5 conditions that must be met to meet genetic equilibrium? (Hardy Weinberg Principle)

Answer 19

• random mating
• large population
• no migration
• no natural selection
• no mutations

Question 20

What is genetic drift?

Answer 20

when a chance event causes allele frequency. AKA bottleneck effect. affects small populations more than large.

Question 21

List evidence for evolution.

Answer 21

• Fossil Record
• Geographic Distribution
• Vestigial Organs
• Homologous Structures
• Analogous Structures
• Embryology
• Molecular Biology

Question 22

What is Geographic Distribution?

Answer 22

Evidence for evolution dating back to Pangaea, when the continents were all one.

Question 23

What are vestigial organs?

Answer 23

Structures that no longer serve a function like the appendix.

Question 24

What are homologous structures?

Answer 24

Structures that have different mature forms but develop from same embryonic tissues.

Question 25

What are analogous structures?

Answer 25

Similar function structures but did not evolve from a common answer, but because of similar habitats. Ex: wings

Question 26

What is embryology and how does it support evolution?

Answer 26

Embryology is the study of embryos and it helps support evolution by comparing the embryonic stages of many different species.

Question 27

How does molecular biology support evolution?

Answer 27

Similarities in DNA sequences suggest evolutionary relationships

Question 28

Who is Thomas Malthus and how did he influence Darwin?

Answer 28

• english economist that wrote books stating that babies are being born faster than people are dying
• predicted if this trend continues we would run out of resources

Question 29

What is the caring capacity of a population?

Answer 29

When your population reaches its point of crisis where there are not enough resources

Question 30

What did Jean-Baptiste Lamark do to influence Darwin?

Answer 30

Deviled the flawed hypothesis that acquired traits could be passed from parents to offspring.

Question 31

What 3 observations did Darwin make on the HMS Beagle?

Answer 31

1. Species varied globally
2. Species varied locally
3. Species varied over time

Question 32

How did Charles Lyell influence Darwin?

Answer 32

He wrote principles of geology and devised uniformitarianism - the idea that we must explain past events with processes that we can observe now

Question 33

What did Alfred Wallace do?

Answer 33

Sent Darwin a report containing his idea of evolution?

Question 34

What is Descent with Modification?

Answer 34

Each living species has descended with changed from other species over time. Common ancestor links all species.