2007 ppr3

Biologi SPM

Kertas 34551/3

(a) Classifing

material apparatus

2% sodium hydrogen carbonate solutionhydrilla

60 w bulbRulerBoiling tubeClip paperretord stand

(b) Record Data

Distance between light source and hydrilla

the total number of bubbles released

60 cm 10

50 cm 12

40 cm 15

30 cm 20

(c)(i)Observing –what can be seen from data(result)

P1: MVP2: RVP3: the RESULT (value with unit)

Samples answer• At the distance of 60cm (P1), the the

total number of bubbles released (P2) is 10 (P3)

• At the distance of 30cm (P1), the the total number of bubbles released (P2) is 20 (P3)

(c)(ii) Making Inferens- based from question/aim of experiment

P1: light intensity (mv- based from aim of experiment) P2: rate of photosynthesis (mv- based from aim of

experiment) R: gas oxygen is produced by plant

Any 2 points get 3 marks

Samples answer• when the light intensity decrease (P1), the rate of

photosynthesis decrease (P2) because less gas oxygen is produced by plant (R)

• when the light intensity increase (P1), the rate of photosynthesis increase (P2) because less gas oxygen is produced by plant (R)

tips : make sure no repetition sentences from observation

(d) Controlling variables

Variables Particular to implemented

ManipulatedDistance between the light sources

Changes the environmentPlaces the simple potometer / apparatus in different environment ,a room with air movement and then (in a room) without air movement / still air

Responding the total number of bubbles released // rate of photosynthesis

Record and count the total number of bubbles released using a stopwatch // record & calculate the rate of photosynthesis using the formula (formula must be stated)=

Controlled time taken for counting the total number of bubble release

Fixed at 5 minutes

(e)Stating hypothesis

P1 – state the manipulated variableP2 – state the responding variableP3 – state the relationship between K1 and K2

If the light intensity (P1) in the increases (P3), the rate of photosynthesis (P2) also increases (P3)

* if vice versa gets only 1 mark EXAMPLE: MV increase, RV Increase/decrease

(f)(i) construct tableDistance between the light sourcesIn 5 min (cm)

60 50 40 30

Total number of bubbles released in 5 minutes

10 12 15 20

Light intensity (1/cm) / cm-1

0.017 0.020 0.025 0.033

T –table, D –data

C - calculation

(f) (ii)Interpret data

(g) [KB0607 – Using Spatial and Time Relationship]

R-relationship based from graphE1: rate of photosynthesis increaseE2: more oxygen gas is produced

the light intensity in the increases ,therate of photosynthesis also increases(R) because more oxygen gas is produced (E1) and rate of photosynthesis

increase(E2)

If relationship is wrong, any E is rejected0 mark

(h)prediction

Able to predict correctly and explain the prediction based on the following criteria ;P1 – total numbers of gas bubbles released increaseP2 – the rate of photosynthesis increaseP3 – 2 sprigs have more leaves

Sample question :total numbers of gas bubbles released increase and the rate of photosynthesis increase because 2 sprigs have more leaves

(i)Defining by operation]

K1 –gas bubble released oxygen produced(from result)K2 –occuring in Hydrilla sp. Which place in sodium hydrogen carbonate solution (based from diagram or informaton given in question)K3 – hypothesis (data) when the distance between light source and hydrilla increase, the number of bubbles released in 5 minutes decrease

Sample answer :Photosynthesis is gas bubble released (K1) which occuring in Hydrilla sp. Which place in sodium hydrogen carbonate solution (K2) .