variation and genetic engineering

Question 1

theory of evolution=

Answer 1

all species have evolved from simple life forms

Question 2

variation

Answer 2

the differences in characteristics of individuals in a population

Question 3

natural selection

Answer 3

organisms that gain advantage are more likely to survive and breed

• they pass on the advantageous gene which results in the population adapting

Question 4

mutation=

Answer 4

change in the DNA code

Question 5

mutation pros

Answer 5

can introduce new variants into a gene of a species

if the new phenotype is suited to environmental change, the species can change quickly

Question 6

mutation cons

Answer 6

rarely produces a beneficial adaptation

rarely gives advantage if there is environmental change

some can be life threatening

many have no effect on the phenotype

Question 7

mutations can happen when…

Answer 7

the cells divide (they divide continuously)

Question 8

evolution summary, 3 points

Answer 8

1 Individuals within a species have a range of variation

2 individuals more suited to the environment will survive and breed

3 the alleles (variants) enabling them to survive are passed on

Question 9

a new species has formed when…

Answer 9

2 populations of a species become so different that they can’t breed to produce fertile offspring anymore

Question 10

selective breeding

Answer 10

humans breeding animals or plants for desired characteristics

Question 11

selective breeding summary 2 points

Answer 11

1 parents with useful / desireable characteristics are bred

2 the offspring they produce is selected again by the ones with the most ideal characteristics

this continues until all offspring show the desired characteristics

Question 12

inbreeding causes issues because

Answer 12

can cause problems because their genetic variation is reduced as a result of selective breeding

Question 13

genetic engineering

Answer 13

when genes are transferred to cells of plants/ animals at an early stage so they develop desired characteristics

Question 14

how is genetic engineering done? 3 lists

Answer 14

1

process: required gene is “cut out” of an organism
how? : using enzymes
example : a person

2

process: gene is inserted into a vector
how? : using enzymes
examples: the vector is usually a virus or bacterial plasmid

3

process: gene is inserted into required cells
how? : using the vector
examples: bacteria, animal, fungi, plants

Question 15

benefits of GM

Answer 15

• genteically engineered micro organisms can take proteins humans need in large quantities and very purely
• developing cures for human disease
• growth of animals and plants
• higher food value of crops
• more GM crops are likely to survive and possible solution to world hunger

Question 16

concerns of GM

Answer 16

• long term effects are unknown
• GM foods could affect human health?
• infertile GM plants and animals could spread into the wild
• fears of human engineering, “designer” human babies.

Question 17

what are the three causes of variation?

Answer 17

• genes
• environment
• a combination of both (like height)

Question 18

how do bacteria become resistant?

Answer 18

• a mutation could make bacterium resistant to antibiotics
• this resistant strain can survive and reproduce without competition from other bacteria
• the population of resistant bacteria will rise
• the resistant strain has now evolved and spreads

Question 19

how can we fight antibiotic resistance?

Answer 19

• they should only be perscribed when necessary
• patients should complete the course
• restricting use of antibiotics in farming

Question 20

why can’t we just make new antibiotics

Answer 20

• takes time and expensive
• we cannot keep up, antibiotic resistant bacteria emerge constantly