natural selectionand GM

Question 1

Charles darwin’s theory of natural selection

Answer 1

Selection pressure (predation, disease and competition) can affect chance of survival.
Alleles responsible for useful characteristics are more likely to be inherited by offspring

Question 2

how did horses evolve to match environment

Answer 2

-originally had high sf area feet for swamp -> third toe became their hood to walk on hard dry ground
-originally small and weak to live in forests -> became larger and stronger to fight off predators in grassland
-teeth were originally small -> became larger and stronger to eat grass

Question 3

what does the pentadactyl limb suggest

Answer 3

many modern vertebrates evolved from a common ancestor, but changed hand shape fit certain conditions

Question 4

how do bacteria gain antibiotic resistance

Answer 4

-natural variation = some have antibiotic resistance
-antibiotic resistance allows some to survive and reproduce, passing on the allele to their offspring

Question 5

evolution of the peppered moth

Answer 5

-white with black spots to live on birch and white lichen
-industrial revolution = polluted air = darkened birch trees. white moths with mutation for dark colour survive
-air became less polluted and birch trees returned to normal. moths with mutation to look white survive

Question 6

5 kingdoms of organisms

Answer 6

animalia
plantae
fungi
protista
prokaryota

Question 7

Order of classification system

Answer 7

Kingdom
Phylum
Class
Order
Family
Genus
Species

Question 8

downsides of selective breeding

Answer 8

-can reduce the gene pool due to inbreeding
-inbreeding can lead to health problems and defects
-reducing variation makes organisms more vulnerable to disease

Question 9

how is genetic engineering carried out

Answer 9

-remove plasmid of DNA to act as a vector
-use restriction enzyme to make a staggered cut in plasmid DNA
-Ligase enzyme inserts the gene into the plasmid through complementary sticky ends
- Reinsert plasmid into bacteria
-GM bacteria will divide into clones to produce the desired protein

Question 10

what is Bt Corn

Answer 10

corn with genes from a soil bacterium inserted into it, making the corn produce a protein with insecticidal properties

Question 11

Why is making GM bacteria easier than making GM plants

Answer 11

In bacteria, DNA is not only in the nucleus because of plasmids in the cytoplasm