CHAPTER 14

Question 1

what are the two types of variation

Answer 1

environmental and genetic

Question 2

what causes genetic variations

Answer 2

the fusion of two sets of dna - one from mother, one from father

Question 3

examples of characteristics influenced only by genes 3

Answer 3

eye colour
inherited diseases
blood group

Question 4

what causes environmental variation

Answer 4

the conditions and environment organism lives and grows in

Question 5

definition of environmental variation

Answer 5

differences between organisms of the same species due to differences in their surroundings

Question 6

definition of genetic variation

Answer 6

the combination of two sets of dna leading to different characteristics in the offspring

Question 7

examples of characteristics caused by environmental variation 3

Answer 7

suntan
education
height in plants

Question 8

what are most characteristics caused by

Answer 8

both environmental and genetic variation

Question 9

what is natural selection

Answer 9

the organisms with the most suitable characteristics for the environment survive and pass on these successful alleles

Question 10

what is a mutation

Answer 10

a change in genetic code

Question 11

what does evolution through natural selection suggest

Answer 11

only the most well adapted to an environment will survive and pass on their alleles, leading to changes in the characteristics of organisms

Question 12

4 key steps in natural selection

Answer 12

mutation of a gene
advantages of survival
breed
pass on genes

Question 13

what will mutation very rarely lead to

Answer 13

a new phenotype

Question 14

example of mutation in action

Answer 14

giraffes having long necks to be able to reach leaves

Question 15

what is the phenotype caused by

Answer 15

genes

Question 16

what is speciation

Answer 16

development of a new species

Question 17

how does speciation occur

Answer 17

the phenotype of an organism changes so much that a completely new species is formed

Question 18

what is extinction

Answer 18

no individuals of a species remain

Question 19

3 reasons for extinction

Answer 19

new predator
new disease
catastrophic event eg natural disasters

Question 20

what is selective breeding

Answer 20

breeding two specific parents to produce offspring with a desired characteristic

Question 21

examples where selective breeding is used 3

Answer 21

cows producing more milk
crops with disease resistance
pets with good temperament

Question 22

basic process of selective breeding

Answer 22

select parents with desired characteristic breed them together
select the offspring with the best characteristic and breed these continue until all offspring have trait

Question 23

problems with selective breeding 2

Answer 23

inbreeding causing health problems

new diseases/ changes in the environment - no variation to adapt

Question 24

what is inbreeding

Answer 24

when two animals that are closely related are bred

Question 25

what is genetic engineering

Answer 25

altering the genetic material of an organism by transferring a gene so it has a desired characteristic

Question 26

what is used to cut out a gene in genetic engineering

Answer 26

an anzyme

Question 27

what is the removed gene inserted into

Answer 27

a vector

Question 28

what does the vector do in genetic engineering

Answer 28

it is used to insert the gene into the organisms

Question 29

process of genetic engineering

Answer 29

the gene is isolated and cut out from one organism it is inserted into a vector the vector inserts the gene into the desired cells the organisms grow with the characteristic

Question 30

examples of vectors used in genetic engineering 2

Answer 30

bacteria | viruses

Question 31

examples of where genetic engineering has been used 3

Answer 31

bacteria making insulin gm crops for a higher yield gene therapy

Question 32

what is gene therapy

Answer 32

swapping faulty genes in ill people with working ones to cure the disease

Question 33

why are crops genetically modified

Answer 33

they have increased yields | frost and pest resistant

Question 34

main advantage to increased crop yields

Answer 34

can feed growing population

Question 35

advantages to gm crops

Answer 35

increased yield more nutrients can grow in difficult climates

Question 36

problems with gm crops 3 `

Answer 36

can affect wildflowers we don't fully understand health impacts transplanted genes may mix into environment too form herbicide resistant weeds

Question 37

what is a clone

Answer 37

something that is genetically identical to its parents

Question 38

main way of cloning plants

Answer 38

tissue culture

Question 39

process of cloning by tissue culture

Answer 39

plant cells are put in a growth medium and grow into clones of their parents

Question 40

advantages to tissue culture 3

Answer 40

made quickly preserve rare plants grown all year round

Question 41

alternative way of cloning plants

Answer 41

cuttings

Question 42

process of cloning by cuttings

Answer 42

cutting are taken form parent plant and grown to make clones

Question 43

main way of cloning animals

Answer 43

cuttings are taken form parent plant and grown to make many clones

Question 44

main way of cloning animals

Answer 44

embryo transplants

Question 45

process of embryo transplant

Answer 45

sperm cells taken from animals egg cells taken from another animal the two are combined to form an embryo these cells are unspecialised so can become a whole animal the embryo is split apart and the cells transplanted into the surrogate mother

Question 46

what is adult cell cloning

Answer 46

when a whole new animal is produced from one cell if an adult animal

Question 47

process of adult cell cloning

Answer 47

taking unfertilised egg cells and remove nucleus another nucleus is taken form an adult body cell the nucleus is inserted into the empty egg cell the egg cell is stimulated to divide this created an embryo which is then implanted into the adult female to grow

Question 48

benefits of adult cell cloning 3

Answer 48

animals that are already producing used proteins in their milk can be cloned save animals from extinction bring back extinct species

Question 49

problems with adult cell cloning

Answer 49

reduced variety in an population - unable to adapt to change loss of embryo life 'designer babies'

Question 50

benefits of genetic modification in medicine 3

Answer 50

potential to cure inherited diseases insulin and growth hormones can be made from bacteria or fungi genetically modified mice used to develop cure

Question 51

benefits of genetic modification in agriculture 3

Answer 51

crops can grow in difficult climates | increase yield pest of frost resistance