evolution

Question 1

what is evolution

Answer 1

is the change in gene frequency in a population over time

Question 2

how do organisms change over time

Answer 2

the generally change from simple to more complex and this happens over many generations

Question 3

5 pieces of evidence for evolution

Answer 3

the fossil record
comparative cytology
comparative biochemistry
comparative embryology
comparative anatomy

Question 4

what is a fossil

Answer 4

a direct skeleton or indirect remains of organisms

Question 5

what are direct fossils

Answer 5

skeleton,bones

Question 6

what are indirect fossils

Answer 6

footprints

Question 7

what have scientists found out about older organisms

Answer 7

that older organisms are less complex than younger ones

Question 8

what is comparative cytology

Answer 8

it´s the study of cells
cells are the basic unit of structure and function of living things
many organisms share the same organelles

Question 9

what is comparative biochemistry

Answer 9

many organisms have similar proteins and enzymes
the closer the relationship between organisms the greater their biochemical similarities

Question 10

what is embryology

Answer 10

comparison of early embryonic development reveals similarities

Question 11

what is anatomy

Answer 11

comparing different organisms reveals similarities in anatomical features
each figure is adapted for a certain function in their environment
even though they have some differences the internal structure of these limbs is similar

Question 12

homologous structures

Answer 12

structures are similar and have the same evolutionary origins
(common ancestor)

Question 13

analogous structures

Answer 13

structures have the same function but have no similarities in evolutionary origin

Question 14

what are vestigial structures

Answer 14

vestigial structures are remnants of structures that were function in an ancestral form
Examples -whales with hips+legs

Question 15

first main point of lamarckian evolution

Answer 15

use and disuse
new organs arise according to the needs of the organism and the size of the organ is determined by the degree to which they are used

Question 16

second main point of lamarckian evolution

Answer 16

inheritance of acquired characteristics
these useful characteristics acquired by an individual during its lifetime can be passed to its offspring

Question 17

why is lamarckism wrong

Answer 17

because organisms are not able to change
physical characteristics just because they need/want to
only changes in the dna of a gamete(sex cell) will be passed onto offspring no changes to body cells

Question 18

what are the 5 steps of darwinian evolution

Answer 18

overproduction
variation
competition
natural selection
reproduction
speciation

Question 19

what is overproduction

Answer 19

when there are more offspring produced than can possibly survive

Question 20

what is variation

Answer 20

characteristics vary within any species

Question 21

what are causes of variation

Answer 21

mutations (raw material for evolution)
sexual reproduction involves the sorting and recombination of genes ** this produces and maintains variation within a population

Question 22

what is competition

Answer 22

when there are limited amounts of food,water,mates,space
so the individuals must compete for resources

Question 23

what is natural selection

Answer 23

individuals who are best adapted to their environment will survive and reproduce

Question 24

what is a selecting agent (selective pressures)

Answer 24

something in the environment that causes death or prevents reproduction of organisms
allow those with favorable adaptations to survive and reproduce

Question 25

what does selecting agent (selective pressures) increase

Answer 25

this increases the frequency of the gene within the population

Question 26

what is reproduction

Answer 26

surviving individuals reproduce and pass on their beneficial traits to offspring

Question 27

what is speciation

Answer 27

over many generations favorable adaptations accumulate,gene frequencies change and new species are formed

Question 28

what is geographic isolation

Answer 28

division that separates small groups from main population by geographic barriers

Question 29

what are some geographic barriers

Answer 29

water,mountains,rivers,highways and deserts

Question 30

what is reproductive isolation

Answer 30

if the population have been separated long enough and have become different enough they will not be able to interbreed even if the geographic barrier was removed

Question 31

second set `` examples of evolution

Answer 31

DDT Peppered moth (industrial melanism) Darwin's finches

Question 32

what is DDT

Answer 32

pesticide used to kill mosquitoes and black flies some had a natural mutations that made them resistant to DDt and lived and reproduced and eventually the whole population became resting to DDyt

Question 33

Industrial melanism (peppered moth)

Answer 33

before the industrial revolution white moths existed but after the white trees became black so the white ones died off and the black ones lived

Question 34

Darwin's finches

Answer 34

found that many finches charged common characteristics but had different beaks and sizes,ect. and found there are 14 different kinds and shared a common ancestor

Question 35

adaptive radiation

Answer 35

different or distinct species will fill different roles in the environment because of variation within the population

Question 36

coevolution

Answer 36

when two species evolve in response to each other via natural selection example: cheetahs getting faster to each their pray but then the pray gets faster

Question 37

evolutionary anachronism

Answer 37

a trait that seems out of place in its current environment,but makes sense when viewed in the context of its evolutionary history example: Avocado (the seed is to big for an animal now but back than there was animals to eat it

Question 38

gradualism

Answer 38

slow,gradual and continuous change

Question 39

punctuated equilibrium

Answer 39

species have long periods of stability interrupted by brief periods of significant change

Question 40

miller-urey experiment

Answer 40

modeled conditions of early earth