bio paper 2

Question 1

1st step of reaction time prac

Answer 1

choose person who has has no caffeine that day

Question 2

what is reaction time

Answer 2

time taken to respond to stimulus affected by age/stress/drugs and more

Question 3

2nd step of reaction time prac after choosing person whos has no caffeine

Answer 3

hold ruler vertically facing down towards persons hand

Question 4

3rd step of reaction time prac after holding ruler vertically/facing down

Answer 4

tell them they must catch ruler but not what time they should

Question 5

4th step of reaction time prac after not telling person time you will drop ruler

Answer 5

drop ruler at random time into their hands

Question 6

5th step of reaction time prac after randomly dropping ruler

Answer 6

record where top of finger is when they catch it

Question 7

the quicker the reaction time in reac time prac

Answer 7

the shorter the distance on the ruler

Question 8

6th step of reaction time prac after recording where top of finger is

Answer 8

repeat few more times without caffeine and calculate mean reaction time

Question 9

what is the mean distance reac prac

Answer 9

average reaction time

Question 10

7th step of reac prac after calculating mean reac time

Answer 10

repeat again after person has had caffeinated drink to find affect on reaction time

Question 11

light/gravity plant seedlings prac step 1

Answer 11

line 3 petri dishes with moist cotton wool

Question 12

step 2 of seedling prac after lining petri with cotton wool

Answer 12

put 10 cress seeds in each and leave in warm place to germinate

Question 13

step 3 seedling prac after leaving seedlings to germinate

Answer 13

measure height of seedling once germinated with ruler

Question 14

step 4 of seedling prac after measuring height after germination

Answer 14

put one petri dish in dark cupboard ,one an overhead light and one under light source at angle for a week

Question 15

5th step of seedling prac after choosing light conditions

Answer 15

measure height of seedlings and observe growth under each light condition

Question 16

control variables in seedling prac

Answer 16

same seeds/type
same amount of water

Question 17

observations of seed prac dark seeds

Answer 17

-dark-longest as they grow up searching for light source

-have small/yellow leaves

Question 18

observations seed prac overhead light source

Answer 18

-grow up and be healthy

Question 19

observations of seed prac/angle to light source

Answer 19

grow in direction of light and be healthy

Question 20

last step of seed prac

Answer 20

calculate mean height of overhead vs dark
-dark taller

Question 21

1st step pop size species distribution

Answer 21

divide area you want to sample to grid and use random number generator to choose coordinates

Question 22

2nd step of pop size prac after random number generator

Answer 22

place quadrat on each coordinates

Question 23

3rd step of pop size prac after placing quadrat

Answer 23

count no of organisms of species using quadrat

Question 24

step 4 of pop size prac after counting species

Answer 24

repeat using randomly generated coordinates

Question 25

step 5 of pop size prac after repeating with random coordinates

Answer 25

find mean no of organisms per m2

total no of organisms/no of quadrats

Question 26

step 6 after finding mean no of organisms pop size prac

Answer 26

find pop size
mean no organisms per m2 x total area m2

Question 28

step 1 of light on distibution

Answer 28

Mark out a transect line along the ecological gradient using a tape measure, e.g. from the base of a tree.

Question 29

step 2 of distribution prac after marking transect line

Answer 29

At start of tree find light intensity using light meter

Question 30

step 3 after using light meter distribution prac

Answer 30

at regular intervals along the line, place a quadrat and count no of daisies
estimate %cover

Question 31

1st decay prac

Answer 31

Set up 3 different water baths at different temperatures , e.g. 10/20/30 degrees

Question 32

2nd decay step after choosing water bath temps

Answer 32

Measure out 20cm3 of milk into 3 different beakers.

Question 33

3rd decay step after measuring 20cm3 of milk into 3 beakers

Answer 33

Use universal indicator solution/paper or a pH probe to measure the pH of the milk in each beaker.

Question 34

step 4 decay after using universal indicator

Answer 34

Cover each beaker in cling film and place them in separate water baths.

Question 35

step 5 decay after placing each tube in a water bath

Answer 35

Use universal indicator solution/paper or a pH probe to check the pH of each beaker after 24, 48 and 72 hours. The pH should decrease over time.