chapter 10- evolution, variation, adaptations

Question 1

what is evolution

Answer 1

the gradual change in heritable traits of organisms many millions of years (successive/several generations)

Question 2

what is evolution (as a genetic def)

Answer 2

a change in the allele frequency of a populations gene pool over successive generations

Question 3

heritable traits are encoded for by … and may be transferred between generations as …

Answer 3

genes and may be transferred between generations as alleles

Question 4

darwins obs: organsism produce more… than ….

Answer 4

more offspring than survive

Question 5

darwins obs: theres variation in…

Answer 5

the characteristics of members of the same species

Question 6

darwins obs: some of these characteristics can be…

Answer 6

passed on from one generation to the next

Question 7

darwins obs: individuals that are best adapted….

Answer 7

to their environment are more likely to survive

Question 8

darwins obs: populations do not…

Answer 8

fluctuate significantly

Question 9

What is the name of the mechanism by which evolution occurs

Answer 9

natural selection

Question 10

describe the process of natural selecion (3)

Answer 10

a new ALLELE arising from random mutation

leads to
increased REPRODUCTIVE SUCCESS is inherited by the next generation.

Over many generations, the new allele increases in FREQUENCY in the population

Question 11

principals of NS: over pro…..

Answer 11

over production leads to competition

Question 12

principals of NS: variation due to

Answer 12

mutaion

Question 13

principals of NS: selection via

Answer 13

adaption (surival of the fittest)

Question 14

principals of NS: breed and pass…

Answer 14

on characteristics

Question 15

what is a selection pressure (2)

Answer 15

a factor which affects an organisms chance of survival or ability to reproduce

Question 16

what does density dependent mean

Answer 16

the factors have a greater impact in denser populations

Question 17

what does density independent mean

Answer 17

the factors are not facilitated by high population density, affects all populations regardless of density

Question 18

what are the 5 density dependent factors/selection presures
(p,r,n,d,w)

Answer 18

predators
availability of resources
nutrient supply
disease (pathogenic spread)
accumulation of wastes

Question 19

what are the 3 density independent factors/selection pressures

Answer 19

abiotic factors
weather conditions

Question 20

offspring generally appear similar to their parents deducting that

Answer 20

characteristics are passed on to the next generation

Question 21

organisms have the ability to produce large numbers of offspring and populations in nature tend to remain relatively stable deducting that

Answer 21

there is a struggle for existence

Question 22

no two individuals are identical and organisms have the ability to produce large numbers of offspring and populations in nature tend to remain relatively stable deducting that

Answer 22

individuals with beneficial characteristics are among few who survive

Question 23

what are the types of evidence for evolution

Answer 23

comparative anatomy (homologous structures)
paleontology(fossils)
comparative biochemistry
molecular biology

Question 24

what are homologous structures

Answer 24

anatomical features that are similar in basic underlying structure despite being used in different way

Question 25

what is adaptive radiation

Answer 25

the diversification of a group of organisms into forms filling different ecological niches

Question 26

what is divergent evolution

Answer 26

that organisms all diverge from a common ancestor with different sets of features even though they have the same homologous structure

Question 27

what is an example of comparative anatomy

Answer 27

the pentadactyl limb: mammals, birds, amphibians and reptiles share a similar arrangement of bones in their appendages based on a five digit/component/element limb

Question 28

the homologous structures provide evidence for

Answer 28

divergent evolution

Question 29

what is meant by rock strata

Answer 29

when remains are preserved in rocks that correspond to different geological eras

Question 30

what do fossils show

Answer 30

usually bones but sometimes soft tissue or footprints

Question 31

what are fossils

Answer 31

preserved remains/traces of any organism

Question 32

how does fossil evidence support the idea that evolution has taken place

Answer 32

fossils have changed over time fossils can be dated fossils can show intermediate forms and sequences

Question 33

what is a fossil record

Answer 33

totality of fossils discovered and undiscovered

Question 34

how do fossil records provide evidence

Answer 34

they reveal the features of an ancestor for comparison against living descendants and shows that over tune changes have occurred in the features of living organisms

Question 35

what is intraspecific variation

Answer 35

Intraspecific variation is variation within a species refers to the differences between organisms of the same species

Question 36

what are the causes of variation

Answer 36

nature (genetics) and nurture (the environment)

Question 37

what is interspecific variation

Answer 37

variation between species refers to the differences between organisms of different species

Question 38

What are the four main sources of genetic variation

Answer 38

mutation, random mating, random fertilisation and recombination of homologous chromosomes during meiosis

Question 39

What term is given to variation which falls into clear groups/which only results in distinct characteristics? E.g. blood groups

Answer 39

discontinuous variation

Question 40

which type of variation has the effect from few genes

Answer 40

discontinuous

Question 41

which type of variation is polygenic/controlled by many genes

Answer 41

continuous

Question 42

which type of variation is effected by environmental factors

Answer 42

continuous

Question 43

what type of variation is not effected by the environment

Answer 43

discontinuous

Question 44

What term is given to variation which can be any value within a given range/which results in a range of characteristics? E.g. human height

Answer 44

continuous variation

Question 45

Human populations use drugs to control infectious diseases. Natural selection in bacteria has led to what problem relating to this?

Answer 45

antibiotic resistance

Question 46

antibiotic resistance: bacteria reproduce very rapidly which....

Answer 46

reproduce/replicate so dna alters to become resistant to antibiotics

Question 47

antibiotic resistance: exposure to antibiotics which is the

Answer 47

selection pressure causes resistant individuals to mutate in order to survive

Question 48

antibiotic resistance: non resistant individuals...

Answer 48

died as there was a compettion for survival/survival of the fittest

Question 49

antibiotic resistance: resistant individuals...

Answer 49

reproduce passing allele for resistance onto offspring, so overtime the number of resistant individuals in a population increases as the allele becomes more frequent.

Question 50

histogram vs bar chart

Answer 50

histogram does not have gaps between the bars, so grouping makes it easier to see patterns, the data is also continuous

Question 51

What is meant by the term “pharmacogenomics”?

Answer 51

The study of how a person’s genes affect their response to particular drugs.

Question 52

what is the founder effect

Answer 52

the loss of genetic variation that occurs when a new population (colony) is established by a very small subset of individuals from a larger population

Question 53

the founder effect plays a role in the

Answer 53

emergence of new species

Question 54

what 3 main things need to occur in the emergence of a new species (brief)

Answer 54

gene mutation selection pressure a change in the environment

Question 55

how do the genetics differ between the founder population and the original population

Answer 55

the genetics of the founder population reflects that of its initial members not the original source population

Question 56

what are homologous structures

Answer 56

a similar anatomical structure but not superficial inherited from a common ancestor doing dissimilar functions

Question 57

what are analogous structures

Answer 57

similar superficial structure to perform the same role but anatomical structure is very diffferen

Question 58

analogous structure eg

Answer 58

aquatics forelimbs shark, penguin, dolphin

Question 59

homologous structure eg

Answer 59

pentadactyl limb

Question 60

what type of evolution is linked to homologous structures\

Answer 60

DIVERGENT

Question 61

what type of evolution is linked to analogous structures

Answer 61

ANALOGOUS