Choithram International

CHOITHRAM INTERNATIONAL

CLASS IGCSE [IX]

CLASS TEST

BIOLOGY [0610] MM 30 DATE 10/1/09

Q1 Fig.1 shows a reflex arc involving a finger and a muscle in the arm.

Fig. 1

(a) State two stimuli that can be detected by receptors in the finger.[2]

(b) Using labels from Fig.1, state the site of the cell body of

1. a sensory neurone, 2. a relay neurone. [2]

(ii) State the structure, present in many mammalian neurones, which reduces leakage

of the impulse.[1]

(iii) The impulse takes 0.02 seconds to pass from the finger to the spinal cord, a

distance of 1.5 metres. Calculate the speed of the impulse. Show your working.

Speed [2]

(iv) Although the total distance the impulse travels in the reflex arc is less than 3

metres, the time taken is more than 0.04 seconds. Suggest why the time taken is

more than expected.[1]

(d) (i) Describe what would happen to the muscle and the arm when muscle V receives

the nerve impulse.[2] [TOTAL 11]

Q2 Over-consumption of alcohol is a problem in some countries.

(a) (i) State two long term effects on the body of drinking too much alcohol. [2]

Some alcohol producers have started to promote ‘responsible drinking’.

Fig.2

Fig.2 shows

the label on a bottle of beer.

(ii) Using information from this label, calculate the volume of beer which would provide the recommended daily maximum alcohol intake for a responsible male drinker…….cm3 [1]

Fig.3 shows the relationship between blood alcohol content and the risk of having a road

accident.

Fig. 3

(c) (i) Use the graph to predict the increased risk of a road accident if a driver had a blood alcohol content of 0.10 g per 100 cm3. [1]

(ii) Describe the relationship shown by the graph between blood alcohol content and

the risk of having a road accident.[2]

(iii) With reference to the nervous system, explain how drinking alcohol before driving

increases the risk of having an accident.[3] [Total: 09]

Q3 Jasmine went into a dark room from a bright corridor.

(a) Fig. 4. represents Jasmine’s right eye before and after entering the dark room.

Fig. 4.

(i) Complete Fig. 4. by draw the appearance of the pupil and iris

1. before entering the dark room, [1]

2. a few seconds after entering the dark room. [1]

(ii) Label the following parts of the eye on the first diagram in Fig. 4.

iris pupil sclera [3]

(b) Explain how the size of the pupil was changed when Jasmine went into the dark room.[2]

Q1 ANS

(a) temperature / heat / cold ;

pressure ;

pain / sharpness ;

texture / touch ; [max 2]

(b) ganglion ;

grey matter (of spinal cord) ; [2]

A electrochemical / movement of ions / electric current

R electrons / electricity [1]

(ii) myelin / (fatty) sheath ; [1]

(iii) award two marks if correct answer with units is given

if not, award one mark if

• correct answer with no units

• incorrect answer with correct units

• no answer but correct working

• incorrect answer but correct working

1.5 / 0.02 ;

75, metres per second or m/s or m s–1 or m sec–1 ; [2]

(iv) synapse(s) / gap(s) (between neurones) ; [1]

(d) (i) (V / biceps) contracts ;

arm / elbow, flexes / bends / pulls away from stimulus / AW ; [2]

(ii) allow ecf from (i)

if muscle not identified assume it is V

triceps (muscle) / (muscle) W / antagonistic muscle / opposing muscle, contracts ;

muscle V relaxes / passive stretching of V ;

A ref to W as antagonistic if already said it contracts

R ‘V relaxes that causes contraction of W’ [2]

[Total: 13]

Q2 ANS2 (a) (i) accept other valid responses – must be long-term and not behavioural / social

1 liver, damage / failure / disease / cirrhosis ; R destroys A hardens

2 brain damage / loss of brain cells / loss of neurones / loss of memory / AW ;

3 cancer of correct named part of body ;

mouth / pharynx / oesophagus / gut / pancreas / liver / breast

4 stomach ulcers ;

5 heart disease / stroke / AW ;

6 high blood pressure / hypertension ;

7 alcoholism / addiction / dependence / tolerance ;

8 (risk of) damage, to fetus / pregnant woman’s baby / fetal alcohol syndrome / AW ;

e.g. low birth weight / poor mental development

9 increased risk of miscarriage ;

10 malnutrition / named deficiency disease(s) ;

11 obesity / weight gain ;

12 loss in weight / wasting ; [max. 2]

(ii) (500 x 2 =) 1000 (cm3) ; [1]

(b) (i) (nutrients are) large molecules / need to be small molecules ;

A complex / simple, molecules

(some nutrients are) insoluble / need to be soluble ;

must pass through, intestine wall / capillary wall ;

R ref. to absorption unqualified by wall(s) [max. 2]

(ii) small intestine / ileum / villi ; A duodenum [1]

(iii) fatty acids / glycerol / maltose / peptides / AW ; R fat / lactose / sucrose [1]

(ii) as blood alcohol content of blood increases, so does risk of accident / AW ;

relevant comment on part of graph ;

use of figures ;

little increase in risk up to, 0.05 / 0.075, g 100 cm-3

greater increase in risk above, 0.05 / 0.075, g 100 cm-3

comparative use of figures – must use figures from both axes [max. 2]

(iii) 1 depressant ;

2 slows down nerve impulses ; R ‘signals’ / ‘messages’

3 slows down / increases, reaction / response, time(s) ;

A ref to reflexes R reaction time decreases

4 e.g. for stimulus or response – traffic lights / braking / swerving / stopping / AW ;

5 blurred / double / impaired / poor, vision AW ;

6 poor / lack of, co-ordination / AW ; A dizziness

7 overconfidence / poor decision making / memory impaired ;

8 poor judgment (of distances) ;

9 sleep / drowsiness / less conscious / AW ;

10 poor concentration / less aware ; [max. 3

[Total: 13]

Q3(a) (i) pupil drawn in both diagrams + smaller in first diagram ;

iris in both diagrams the same diameter ; [2]

(ii) labels correct for:

iris ;

pupil ;

sclera ; [3]

(b) (pupils gets bigger)

ref. to contraction + of radial muscles ;

ref. to relaxation of circular muscles ; [2]

ref. to sensitivity even in low light intensities AW ;

ref. to role of cones in detecting colour AW ;

ref. to cones needing high light intensity to trigger them AW ; [max. 3]

[max. 10]