MOCKS USE OF BIOLOGICAL RESOURCES

Question 1

5.10 & 5.11 what is selective breeding

Answer 1

the steps taken to select a particular feature in an organism

Question 2

5.10 why are plants selectively bred by humans

Answer 2

disease resistance in food crops
increased crop yield
hardiness to weather conditions (e.g. drought tolerance)
better tasting fruits
large or unusual flowers

Question 3

5.10 problems with selective breeding in plants

Answer 3

can lead to inbreeding
when the plants which are closely related to each other are bred together
there’s a reduction in the gene pool & less alleles (different versions of genes) in a population
increased chance of inheriting harmful genetic defects
can be vulnerable to new diseases - less chance of resistant alleles being present in the reduced gene pool

Question 4

5.10 list of steps to selective breeding in plants

Answer 4

choose plants with desired feature / characteristic
let those breed & reproduce
choose offspring that have desired feature
let only those breed together
repeat for many successive generations before having a ‘new breed’ that will reliable show the desired feature

Question 5

5.10 examples of selective breeding in plants

Answer 5

crops that are resistant to certain diseases

Question 6

5.11 examples of selective breeding in animals

Answer 6

cows that produce the most milk
cattle that produce lots of meat

Question 7

5.11 why are animals selectively bred by humans

Answer 7

cows, goats and sheep that produce lots of milk / meat
chickens that lay large eggs
domestic dogs with a gentle nature
sheep with good quality wool
horses with fine features & a very fast pace

Question 8

5.11 problems with selective breeding in animals

Answer 8

can lead to inbreeding
when the animals which are closely related to each other are bred together
there’s a reduction in the gene pool & less alleles (different versions of genes) in a population
increased chance of inheriting harmful genetic defects
can be vulnerable to new diseases - less chance of resistant alleles being present in the reduced gene pool

Question 9

5.11 list of steps to selective breeding in animals

Answer 9

choose animals with desired feature / characteristic
let only those breed & reproduce
choose only offspring that have the desired feature
let only those reproduce
repeat for many successive generations

Question 10

5.11 natural selection versus artificial selection in selective breeding

Answer 10

natural:
occurs naturally
development of populations with features better adapted to their environment and survival
usually takes a long time to occur

artificial:
only occurs when humans intervene
development of populations with features not useful to humans / necessarily useful to the survival of the individual
takes less time as only individuals with desired features are allowed to reproduce

Question 11

5.7 what is yoghurt made with

Answer 11

lactobacillus bulgaricus

Question 12

5.7 first the milk is p… to ?

Answer 12

pasteurised to kill bacteria

Question 13

5.7 the mixture is maintained at 46*C so

Answer 13

the bacterias enzymes are not denatured

Question 14

5.7 lactobacillus respires anaerobically producing

Answer 14

lactic acid

Question 15

5.7 how does lactobacillus respire

Answer 15

anaerobically

Question 16

5.7 what does lactic acid do

Answer 16

lowers the pH
coagulates the milk protein
gives yoghurt its texture and flavour

Question 17

5.7 steps to produce yoghurt

Answer 17

sterilise equipment
pasteurise milk by heating
add bacterial culture to
cooled milk
leave at 46C for 4 hours
take samples if yoghurt is ready
add flavour and colour
cool yoghurt to 5C to preserve
package yoghurt

Question 18

5.7 what is lactobacillus bulgaricus

Answer 18

it is a bacteria

Question 19

5.7 why is yoghurt sour and has its unique taste

Answer 19

because of the anaerobic reaction creating lactic acid