Ch.4 population change

Question 1

Adaptation

Answer 1

structural, behaviour or physiological process that helps an organism survive + reproduce

Question 2

Why adapation

Answer 2

makes species will suited for envionemnt, is a result of gradual change in characteristics over time

Question 3

variation

Answer 3

visible or invisible differences that help survive

Question 4

why variation

Answer 4

not all become adaptations some do, can be helpful, harmful or neither- some adaptations increase survival

Question 5

why are organisms differenet

Answer 5

bc/ of mutations and sexual reproductions

Question 6

mutations

Answer 6

change in DNA of cell

Question 7

more mutations

Answer 7

occur spontaneously, can be induced by mutagens: UV light, chemicals,- mutations on gametes inherited, DNA mutates helpful or cell die, when helpful gives selective advantage

Question 8

sexual reproduction

Answer 8

off-spring have combo of genetic info from both parents

Question 9

why sexual repoduction

Answer 9

produces variation, off-spring have different DNA, many parents with different genes

Question 10

how more variation

Answer 10

reproduce often- increases # of mutants, sexual reproduction w no similar mates - increases variability

Question 11

natural selection

Answer 11

process that results when characteristics of population of organisms change, more favourable ones stay

Question 12

Key points of NS

Answer 12

needs variation with species, better traits survive and reproduce and more offspring, intra-specific competition better for favourable traits will reproduce the most, traits get passed down (selective advantage)

Question 13

evolution

Answer 13

change in population overtime
- individuals can’t genetically evolve

Question 14

Comte de Buffon

Answer 14

publicly challanged idea of no evolution, suggested common ancestry, earth >6000,

Question 15

Cuvier

Answer 15

different layers of rock = different fossils - deeper = not similar, evidence of species extinction not evolution, proposed Catastrophism

Question 16

catastrophism

Answer 16

all major changes on earth caused by catastrophies

Question 17

Lyell

Answer 17

rejected catastrophism, natural process operated at same rate as in past, earth >6000, slow process over time = big change

Question 18

Lamarck

Answer 18

the first theory of evolution
theory of inheritance of acquired characters - organisms change bc environment, change from simple to complex until perfection, use of disuse of traits passed to off-spring

Question 19

Darwin + Wallace

Answer 19

theory of natural selection
origin of species - organisms today are modifications of ancestors, different species adapted to environment evolve

Question 20

evidence of evolution

Answer 20

fossil record, transitional fossils, patters of distribution (biogeography), anatomical, embryology, molecular biology + genetics

Question 21

molecular biology + genetics

Answer 21

all cels have DNA, carbs, H2O, proteins, cell membrane - more similar molecules made by organisms more related

Question 22

embryology

Answer 22

similar embryos in related groups point to same ancestor

Question 23

anatomical evidence

Answer 23

homologous: same structure different function
analogous: similar function no common ancestor

Question 24

biogeography

Answer 24

study of past + present geological distribution of organisms, more similar organism found geographically close, on island organism similar to animals on land close to it

Question 25

transitional fossils

Answer 25

show intermediary links between groups, helps scientists understand process + relationship between groups

Question 26

fossil record

Answer 26

appear in chronological order, fossils in upper layer more similar to today

Question 27

speciation

Answer 27

formation of new species

Question 28

transformation

Answer 28

one turn into another, caused by environmental changes/pressures, original species no longer

Question 29

divergence

Answer 29

one splits into 2, caused by separation of members then separate evolution, results in reproductivly isolate populations

Question 30

geographical barriers

Answer 30

physical abt environment that separates, eg: lakes, continents, dams, isolation not forever but until not compatible reproductively

Question 31

biological barriers

Answer 31

behavioral factors prevent members from breeding

Question 32

prezygotic barrier

Answer 32

biological barrier before fertilization - habitat, behaviour, temporal, mechanical, gametic isolation

Question 33

postzygotic barriers

Answer 33

biological barrier after fertilization, 'hybrid instability - reduced hybrid viability/fertility, hybrid breakdown

Question 34

adaptive radiation

Answer 34

single species rapidly adapt to fill available niches in the environment

Question 35

pace of evolution

Answer 35

amount of genetic variation- more offspring with variation, more pressure to adapt - changing environment and more predators

Question 36

gradualism

Answer 36

evolution occurs gradually at steady rate, small change over time = big change

Question 37

punctuated equilibrium

Answer 37

evolution of species occurs mostly on show period of time has great change then long time with very little change