B14 - Variation

Question 1

variation

Answer 1

differences in the characteristics of individuals in a population

Question 2

variation due to

Answer 2

inherited
-environment
-or both

Question 3

Natural selection

Answer 3

organisms are in competition with members of the same species
-ones that are at an advantage survive and breed

Question 4

Variation within a species

Answer 4

genes are inherited

Question 5

new variants

Answer 5

result of mutation
-Change in dna code

Question 6

mutations when gametes are formed

Answer 6

affect phenotype
-new variants into genes

Question 7

mutations rarely

Answer 7

produce an adaptation for the organism

Question 8

theory of evolution by natural selection

Answer 8

all species have evolved from simple life forms
-produces a change in inherited characteristics
better adapted species

Question 9

process of natural selection + evolution

Answer 9

• genetic variation within species
• better adapted individuals survive + breed
  -alleles that are well adapted are passed on

Question 10

when do two population split and become their own species

Answer 10

when they can no longer interbreed to produce fertile offspring

Question 11

rapid change in species due to

Answer 11

a new phenotype which is better suited to the environment

Question 12

selective breeding

Answer 12

speeds up natural selection by selecting animals or plants for breeding that have a required characteristic

Question 13

Farmers eg of selective breeding

Answer 13

-select ones with desirable characteristics
-forms a breeding stock

Question 14

Desirabl characteristics eg

Answer 14

-disease resistant crops
-animals that produce more meat/milk
-gentle nature dogs
-heavily scented flower

Question 15

con of selective breeding

Answer 15

strange combination of genes that wouldn’t have occured naturally
- reduced variation
-inbreeding

Question 16

pro of selective breeding

Answer 16

useful organisms have been produced

Question 17

inbreeding causes

Answer 17

pront to disease + inherited defects
-lack of variation

Question 18

lack of variation means

Answer 18

-reduces number of alleles
-if conditions are unstable and changes
-won’t be able to cope with change
-death of species

Question 19

geentic engineering

Answer 19

involves modifying genetic material of an organism

Question 20

process of genetic engineering

Answer 20

enzymes isolate + cut out required gene
-inserted into vector using more enzymes
-genes are transferred at an early stage
-organism grows to develop this characteristic

Question 21

vector used genetic engineering

Answer 21

usually bacterial plasmid / virus

Question 22

plants genetic engineering

Answer 22

desired genes inserted into meristemc ells
-used to produce identical clones

Question 23

GM bacteria/fungi

Answer 23

-cultred on a large scale
-make lots of protein (insulin)
-but there is a limit to hm protein is made

Question 24

GM crops

Answer 24

-increases yield + size + nutrition
-resistant to disease/ insect
- resistant to herbicide

Question 25

GM crops - resistant to insects

Answer 25

-make their own pesticide

Question 26

GM crops - resistant to herbicide

Answer 26

- farmers can kill weed w/o damaging crops

Question 27

clone

Answer 27

individual produced asexually and genetically identical to parent

Question 28

tissue culture = cloning

Answer 28

-expensive -allows many clones to be made from a small piece of tissue

Question 29

process of tissues culture

Answer 29

-mixture of hormones to group cells that are needed -produces a callus -using hormones/right conditions = stimulates growth of cells to be a new plant

Question 30

callus

Answer 30

big mass of identical plant cells

Question 31

Tissue culture pros

Answer 31

-high quality w desired qualities -used commercially in plant nurseries -preserves rare plant species

Question 32

taking cutting

Answer 32

-older + simpler -produces identicalt o parent plant -used by gardeners

Question 33

Cloning cattle embryos process

Answer 33

-fertility hormones to top quality cow to produce may eggs -fertilise egg w sperm -embryonic cells are split and transplanted into surrogate -produces identical twins

Question 34

Cloning cattle embryos process - fertilisation

Answer 34

-inside a cow and embryos are washed out of uterus -or eggs are collected and fertilised in a lab

Question 35

pros of Cloning cattle embryos process

Answer 35

-produces more calves -produces GM embryos = useful -carried to places in need (dry areas)

Question 36

cons of Cloning cattle embryos process

Answer 36

-expensive -highly skilled work

Question 37

can mamals reproduce asexually

Answer 37

never

Question 38

adult cell cloning

Answer 38

-new whole animal is produced from the cell of another adult animal

Question 39

adult cell cloning proces

Answer 39

- nucleus is removed from unfertilised egg - nucleus is removed from an adult body cell - nucleus is inserted into egg cell -electric shock = stimulates division to from embryonic cells -embryo is inserted into surrogate

Question 40

pros of adult cell cloning

Answer 40

-produce useful proteins in milk -produces medically useful animals -prevents extinction and brings back species -clones pet = dna lives on but ethical concerns

Question 41

risks of adult cell cloning

Answer 41

-cloning human babies = ethical concerns -reduces variation

Question 42

benefits of genetic tech

Answer 42

- curing inherited disorders by replacing faulty genes -produce proteins for humans from GM organisms (insulin) - GM mice to mimic human disease = cure

Question 43

Pros of genetic tech in agriculture

Answer 43

-improved growth rates of plants -increase food value + yield -drought resistant - herbicide resistant + makes own pesticides

Question 44

Concerns of genetic tech agriculture

Answer 44

-GM food can affect human diet - GM organisms on nature - fears human engineering (designer babies)

Question 45

Concerns of genetic tech agriculture - GM organisms on nature

Answer 45

- they are infertile = farmers repurchase seeds -if infertile genes spread damage ecosystems