2020 p2

Question 1

Name 2 types of micro organism that cause decay

Answer 1

-bacteria
-fungi

Question 2

why did it take the different types of milk different times to reach pH 5

Answer 2

-different types of bacteria
-contain different concentrations of lipids

Question 3

Describe how fishing quotas can help to return fish stocks to a sustainable level

Answer 3

fewer fish caught so the remaining fish can reproduce

Question 4

Why are people concerned about the increase of gentically modified crops

Answer 4

decreases biodiversity (or decrease in gene pool)

Question 5

Give 2 uses of gibberellins

Answer 5

-increase fruit size
-promote flower production
-start germination

Question 6

Why does storing bananas with other fruits cause them to ripen faster

Answer 6

ethene is released

Question 7

Describe structure of a nucleotide

Answer 7

phosphate
-attatched to a sugar
with 1 base attatched to sugar
bases are GCAT

Question 8

how do the non-coding parts of dna affect expression of genes

Answer 8

can switch genes on/off

Question 9

give 3 differences between meiosis and mitosis

Answer 9

-mitosis creates genetically identical offspring but meiosis uses dna from both parents
-mitosis produces 2 cells but meiosis produces 4 cells
-one cell division in mitosis, two cell divisions in meiosis

Question 10

give a similarity between meiosis and mitosis

Answer 10

DNA replicates

Question 11

Name part of brain that controls balance

Answer 11

cerebral cortex

Question 12

Describe how brain receives information about light entering the eye

Answer 12

retina sensitive to light, impulse passes along sensory neurone and along optic nerve to the brain

Question 13

Describe natural selection-evolution

Answer 13

-random mutation in gene
-causes.. (LINK)
-animals with mutation can.. (LINK)
-therefore they are more likely to survive and reproduce
-by natural selection
-they pass on useful gene to offspring
-this them repeats over many generations resulting in evolution

Question 14

Why is some biomass lost from animal 1 to animal 2

Answer 14

-not all parts of animal 1 is eaten
-urea is excreted from animal 2

Question 15

why is needing to farm less good

Answer 15

less livestock(cows) which release methane into atmosphere so less global warming
less harmful effects of global warming on food production (e.g farmland)

Question 16

Give 3 reasons why fossil record is not complete for older species

Answer 16

-bones buried deeper under ground so harder to find
-organisms soft bodied so most of tissue decayed
-more likely to be destroyed by earthquakes

Question 17

Give an advantage and a disadvantage of mass extinction events

Answer 17

advantage: loss of biodiversity
disadvantage: allows new species to evolve