Markscheme Bio 3 Trial Selangor 2007

Markscheme bio 3 trial selangor 2007

Paper 3 (4551/3) 1 (a) (i) [KB0601 - Observation] Score Criteria 3 Able to state any two observations correctly according to the criteria: • Fan speed • Initial and final weight • Comparison (higher or lower) Sample answers: 1. At fan speed 0, the weight loss is smallest that is 0.9g/ initial weight is decreased by 0.9g 2. At fan speed 3, the weight loss is highest that is 69.70g / initial weight is decreased by 69.7g

2

Able to state any one observation correctly. or Able to state any two incomplete observations ( any 2 criteria) Sample answers: 1. At fan speed 0, the weight loss is smallest / initial weight is decreased 2. At fan speed 3, the weight loss is highest / initial weight is decreased

1

Able to state any one idea of observation.(any 1criteria) Sample answers: 1. Different speed of fan cause different weight loss. 2. The higher speed of the fan, the higher weight loss. 3. Speed of fan used affects the weight loss. 4. Air movement cause weight loss.

0

Not able to response or wrong response.

1 (a) (ii) [KB0604 - Making inferences] Score Criteria 3 Able to make one logical inference for each observation based on the criteria • Fan speed • Condition of air movement • More/less water loss Sample answers: 1. At fan speed 0, the air movement is slow, so less water loss. 2. At fan speed 3, the air movement is fast, so more water loss.

Markscheme bio 3 trial selangor 2007

2

Able to make one logical inference for any one observation. or Able to make one logical and incomplete inference base on 2 criteria for each observation. Sample answer: 1. Different speed of air movement will causes different weight loss 2. Different speed of air movement causes different transpiration rate.

1

Able to make an idea of inference with one criteria. Sample answers 1. Air movement affect transpiration rate 2. Transpiration rate vary at different speed of air movement

0

Not able to response or wrong response.

(b)(i) [KB0606 – Communicating] Score 3

Criteria Able to draw a table with all column and row labeled with complete unit Sample answers Fan speed

Weight Loss/ (water loss) (g)

Transpiration rate (g/min)

0 1 2 3 2 1 0

Able to draw a table with 2 label of column. Able to draw a table with 1 label of column Not able to response or wrong response.

(b)(ii) [KB0603 – Measuring Using Number] Score 3

2 1 0

Criteria Able to calculate and record all the weight loss and the transpiration rate Sample answers Weight loss/ Transpiration rate (water loss) (g) (g/min) 0 0.90 0.03 1 18.60 0.62 2 40.50 1.35 3 69.70 2.32 Able to calculate and record 5-7 the weight loss and the transpiration rate Able to calculate and record 2-4 the weight loss and the transpiration rate Not able to response or wrong response.

Markscheme bio 3 trial selangor 2007

(b) (iii) [KB0607 – Interprating Data] Score Criteria 3 Able to state clearly and accurately the relationship between the air movement, water loss with the rate of transpiration base on: • Air movement • Water loss • Transpiration Sample answer: 1. Slow air movement causes less water loss due to less water being transpired out by the plant 2. High air movement causes more water loss due to more waterbeing transpired out by the plant 2

Able to state clearly but less accurate the relationship between the air movement, water loss with the rate of transpiration base on 2 criteria: Sample answer: 1. Slow air movement causes less water transpired out by the plant 2. High air movement causes more water transpired out by the plant

1

Able to state the idea of the relationship between increasing the air movement speed with the rate of transpiration, base on 1 criteria 1. water loss Air movement will affect the transpiration process / water loss from the plant

0

Not able to response or wrong response.

(c) [KB061001 – Controling Variables] Variables Manipulated: Air movement / fan speed Responding: Weight loss / rate of transpiration Fixed: Light intensity Time

How the variables are operated Fan is switched on at different speed Calculating the difference in weight at the beginning and end of experiment/ calculating weight loss/ calculating the rate of transpiration using formula. Experiment is done at same lighted place/ Time is fixed to 30 minutes for every experiment.

Score : Score 3: 5 - 6 correct answers

Markscheme bio 3 trial selangor 2007 Score 2: 3 - 4 correct answers Score 1: 1 - 2 correct answers

(d) [KB0611- Making Hypothesis] Score Criteria 3 Able to state a hypothesis to show a relationship between the manipulated variable and responding variable and the hypothesis can be validated, base on 3 criteria: • manipulated variable • responding variable • relationship Sample answer : The higher the speed of the fan, the higher the rate of transpiration/ The higher the speed of the fan, more water is lost due to transpiration 2

Able to state less accurate hypothesis to show a relationship between manipulated variable and responding variable base on 2 criteria. Sample answer 1. Different speed of air movement causes different rate of transpiration 2. Different speed of air movement causes different amount of water lost

1

Able to state idea of hypothesis to show a relationship between manipulated variable and responding variable base on 1 criterion. Sample answer 1. Air movement causes different rate of transpiration 2. Air movement causes different amount of water loss 3. Air movement affect amount of water loss/ transpiration rate.

0

Not able to response or wrong response.

(e) [KB0608 – Space and Time Relationship] Score Criteria 3 Able to state clearly and accurately the relationship between increasing the air movement speed with the rate of transpiration base on criteria: • Speed increases /decreases air movement • Effect on transpiration process • Relationship Sample answer: 1. Increasing speed of air movement will speed up the transpiration process / speed up water loss from the plant. 2. Decreasing speed of air movement will slow down the transpiration process/ slow down water loss from the plant.

Markscheme bio 3 trial selangor 2007 2

Able to state clearly but less accurate the relationship between increasing the air movement speed with the rate of transpiration base on 2 criteria Sample answer: 1. Increasing speed of air movement affects the transpiration process / affects water loss from the plant. 2. Air movement affects the transpiration process / water loss from the plant.

1

Able to state the idea of the relationship between increasing speed of the air movement speed with the rate of transpiration, base on 1 criteria Sample answer: 1. Amount of water loss depend on air movement 2. Different speed of water movement causes different rate of transpiration

0

Not able to response or wrong response.

(f) [KB0609 [Define operationally] Score Criteria 3 Able to explain the transpiration process base on experiment correctly: Sample answer:

1. Transpiration process is the loss of water from the plant shoot shows by weight loss and affected by air movement. 2

Able to state the transpiration process base on experiment: Sample answer: 1. Transpiration is the loss of water from the plant shoot affected by air movement.

1

Able to state the idea of the transpiration or the theoretical definition of transpiration 1. Transpiration is the loss of water from the plant shoot. 2. Transpiration is the process of evaporation of water from the plant.

0

Not able to response or wrong response.

(g) [KB0605 – Predicting] Score 3 Able to predict the result accurately. • Expected transpiration rate • Compare to which • The reason of the answer

Criteria

Sample answer: Transpiration rate at fan speed 3, in the dark less than 2.32g/min, because the stomata are closed in the dark, less water evaporate from the plant shoot.

Markscheme bio 3 trial selangor 2007

2

Able to predict the result less accurate: Sample answer: Transpiration rate at fan speed 3, in the dark less than 2.32g/min

1

Able to give idea of the result Transpiration rate is low Water loss is less.

0

Not able to response or wrong response.

(i) [KB0602 – Classifying] Score Criteria 3 Able to classify the apparatus and materials used in this experiment according to their purpose in this experiment. Sample answer the apparatus and materials their purpose in this experiment used Weighing scale Measuring the weight Set- up P For experimenting Fan To control speed of air movement Stopwatch To set the time used. Able to classify 4 apparatus and materials used in this experiment 2

Able to classify 3 apparatus and materials used in this experiment

1

Able to classify 1-2 apparatus and materials used in this experiment

0

Not able to response or wrong response.

Markscheme bio 3 trial selangor 2007

QUESTION 2

Markscheme bio 3 trial selangor 2007 Aspect KB061201 Objective Identifying Problem Statement

Criteria Able to state the objective of the experiment correctly Able to write a problem statement correctly Sample Answer Sample Answer • To determine the oxygen and carbon dioxide content in • Does air contain more oxygen and less carbon inhaledinhaled and exhaled air dioxide than exhaled air? Able to write a problem statement but less correctly Sample Answer • Does inhaled air contain more oxygen than exhaled air? // • Does exhaled air contain less carbon dioxide than exhaled air? // • Does inhaled and exhaled air contain oxygen? // • Does inhaled and exhaled air contain carbon dioxide? // • Does inhaled air contain oxygen and carbon dioxide? // • Does exhaled air contain oxygen and carbon dioxide? Able to give an idea about the problem statement. Sample Answer • Does inhaled air contain oxygen/carbon dioxide? // • Does exhaled air contain oxygen/carbon dioxide? Wrong or no response Sample Answer • Does exhaled air contain more oxygen and less carbon dioxide than inhaled air? // • Does inhaled air contain more carbon dioxide and less oxygen than exhaled air? // • Does inhaled/exhaled air contain water vapour?

Aspect Variables

Criteria Able to identify all the three variables correctly Sample Answer • Manipulated variable : type of air sample (inhaled or exhaled air) • Responding variable : percentage/quantity of oxygen and carbon dioxide in inhaled and exhaled air • Fixed variable : length/volume of air used/ source of sample/ Able to identify any two variables correctly Able to identify any one variable correctly Wrong or no response

Score

√3

2

1

0

Score

√

√√ √ No tick

Markscheme bio 3 trial selangor 2007 Aspect KB061202 Making hypothesi s

Criteria Able to write a suitable hypothesis correctly Sample Answer • Inhaled air contains more oxygen and less carbon than exhaled air // • Inhaled air contains more carbon dioxide and less than exhaled air // • Exhaled air contains more carbon dioxide and less than inhaled air // • Exhaled air contains more oxygen and less carbon than inhaled air.

Score 3 dioxide oxygen oxygen dioxide

Able to write a hypothesis but less correctly Sample Answer • Inhaled air contains more/less oxygen than exhaled air // • Inhaled air contains more/less carbon dioxide than exhaled air // • Inhaled and exhaled air contain oxygen // • Inhaled and exhaled air contain carbon dioxide // • Inhaled air contains oxygen and carbon dioxide // • Exhaled air contains oxygen and carbon dioxide. Able to give an idea about the problem statement. Sample Answer • Inhaled air contains oxygen/carbon dioxide // • Exhaled air contains oxygen / carbon dioxide // Wrong or no response Sample Answer • Inhaled/exhaled air contains respiratory gases

2

1

0

Markscheme bio 3 trial selangor 2007 Aspect KB061205 Materials and Apparatus

Criteria Able to list all materials and apparatus needed to carry out the experiment successfully. Sample Answer Materials : Potassium hydroxide solution Potassium pyrogallate solution Water Apparatus : J-tube Ruler Beaker Boiling tube Basin / water bath Rubber tubings Able to list materials and apparatus needed to carry out the experiment. Sample Answer Materials : Potassium hydroxide solution Potassium pyrogallate solution Apparatus : J-tube Ruler Boiling tube / beaker Basin / water bath Able to list the basic materials and apparatus needed to carry out the experiment. Sample Answer Materials : Potassium hydroxide solution Potassium pyrogallate solution Apparatus : J-tube Ruler Boiling tube / beaker Incomplete list or wrong or no response

Score 3

2

1

0

Markscheme bio 3 trial selangor 2007 Aspect Technique

Criteria Able to state the technique used in carrying out the experiment correctly Sample Answer • To calculate percentage of carbon dioxide content in inhaled / exhaled air using the formula :

Percentage of CO2

=

_(x – y)_cm x 100% x cm

x = length of air column of inhaled / exhaled air y = length of air column upon adding porassium hydroxide solution z = length of air column upon adding porassium pyrogallate solution

•

To calculate percentage of oxygen content in inhaled / exhaled air using the formula : Percentage of O2

=

_(y – z)_cm x 100% x cm

x = length of air column of inhaled/exhaled air y = length of air column upon adding porassium hydroxide solution z = length of air column upon adding porassium pyrogallate solution

•

To measure the length (and record) of air column occupied by oxygen in inhaled/exhaled air using a ruler

•

To measure the length (and record) of air column occupied by carbon dioxide in inhaled/exhaled air using a ruler

Score B1 = 1

Markscheme bio 3 trial selangor 2007

Aspect KB061204

Able to write successfully.

Criteria all the steps in carrying out the experiment

Score

Procedure K1 K2 K3 K4 K5

: : : : :

Steps to set up the apparatus Steps to handle the fixed variable Steps to handle the manipulated variable Steps to handle the responding variable Precautionary steps / steps taken to get accurate results / readings

Sample Answer Please refer to pg 8 Scoring Rubric All K1-K5 present

3

K1-K4 present

2

Any 3K present

1 0

Less than 3K or wrong response

Markscheme bio 3 trial selangor 2007 Aspect Communicating data

Criteria

Score

Able to draw a complete table to record the relevant data for both inhaled and exhaled air

B2 = 1

Sample Answer Data for inhaled air Length of inhaled air column at the beginning of experiment Length of inhaled air column after treating with potassium hydroxide solution Length of inhaled air column after treating with potassium pyrogallate solution Length of CO2 column in inhaled air

(p –q) cm

Length of O2 column in inhaled air

(q –r) cm

Percentage of CO2 in inhaled air

(p –q) cm x 100% p cm (q –r) cm x 100% p cm

Percentage of O2 in inhaled air

p cm q cm r cm

Data for exhaled air Length of exhaled air column at the beginning of experiment Length of exhaled air column after treating with potassium hydroxide solution Length of exhaled air column after treating with potassium pyrogallate solution Length of CO2 column in exhaled air

(x –y) cm

Length of O2 column in exhaled air

(y –z) cm

Percentage of CO2 in exhaled air

(x –y) cm x 100% x cm (y –z) cm x 100% x cm

Percentage of O2 in exhaled air

x cm y cm z cm

Able to draw a complete table to record the relevant data for either inhaled or exhaled air Able to draw a table to record the relevant data but incomplete Wrong or no response

2 1 0

Markscheme bio 3 trial selangor 2007

Aspect Conclusio n

Aspect KB061203 Experimen ting

Criteria Able to write a suitable conclusion for the experiment. Hypothesis accepted // Hypothesis rejected • Inhaled air contains more oxygen and less carbon dioxide than exhaled air // • Exhaled air contains more carbon dioxide and less oxygen than inhaled air

Score

Hypothesis accepted // Hypothesis rejected only

No tick

Criteria Able to write a complete report for the experiment. Scoring Rubric

√

Score

3

8 – 9 aspects correct 2 6 – 7 aspects correct 1 3 – 5 aspects correct 0 Less than 3 aspects correct Sample Answer K1

Procedure 1. Turn the screw of the J-tube until the end

K1

2. Dip the end of the J-tube in water. Draw into the tube about 5 cm of water.

K1

3. Remove the J-tube from the water. Draw into the tube about 10 cm of air (inhaled air).

K1

4. Dip the open end of J-tube into the water again. Draw in a little more water (to seal the air column).

K1

5. Adjust the screw so that the air column is in the middle of the Jtube.

K5

6. Immerse the J-tube into water bath for 2 minutes, to stabilize the temperature of air sample.

K4

7. Measure the length of the air column using a ruler. Record the measurement as p cm.

K1

8. Expel some of the water in the J-tube leaving about 2-3 mm from the end of the tube.

Notes

Markscheme bio 3 trial selangor 2007 K1

9. Dip the open end of the J-tube into the potassium hydroxide and draw in about 2 – 3 cm of the solution. (Potassium hydroxide absorbs carbon dioxide from the air column).

K1

10. Remove the tube from the solution and move the air column to and fro several times.

K4/K5 K1

11. Repeat step 6 and 7. Record the length of air column as q cm. 12. Expel the potassium hydroxide solution leaving about 2-3 mm from the end of the tube.

K1

13. Repeat step 9 using potassium pyrogallate solution. (Potassium pyrogallate absorbs oxygen from the air column).

K4/K5 K1

14. Repeat step 6 and 7. Record the length of the air column as r cm. 15. Based on the results, calculate the percentage of carbon dioxide and oxygen in the sample of inhaled air column.

K3 K1

16. Repeat steps 1 – 17 using a sample of exhaled air. 17. Compare the percentages of carbon dioxide in inhaled and exhaled air.

K1

18 Compare the percentages of oxygen in inhaled and exhaled air.

5K

=3m

3-4K = 2 m 1-2K = 1 m