ANWERS TO BIOLOGY

Topics: Blood sugar, Concentration, Iodine Pages: 8 (1430 words) Published: April 13, 2015
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General Certificate of Secondary Education
2012

Biology
Unit 1
Higher Tier
[GBY12]
WEDNESDAY 30 MAY, AFTERNOON

MARK
SCHEME

7710.01

1

2

(a) A – Palisade (mesophyll cell);
B – Guard cell;
C – Lower epidermis (cell);

[1]
[1]
[1]

(b) Thin/clear/transparent/no pigment;

[1]

(a) Nerves carry electrical (impulses);
Hormonal system uses chemical (messages);

[1]
[1]

(b) (i)

The larger the diameter of the nerve, the higher/faster the speed (of conduction);

(ii) Faster response/reflex/reaction rate (/time);
Reject: “faster conduction rate” unqualified
3

[1]

[2]

(b) Increased weight/BMI/obesity;
Increased risk of heart disease/heart attack/stroke/high blood pressure/ diabetes/arthritis;

[2]

(c) More energy required for growing/developing embryo;

[1]

(d) Genetics/inherited factors/alcohol/smoking/drugs;

[1]

2

4

[1]

(a) As age increases so does the amount of energy required;
Boys require more energy than girls;

7710.01

AVAILABLE
MARKS

4

6

[Turn over

4

(a) Indicative content:
1
Dish B (/with more iodine) has a larger dark (blue/black) area than dish A;
2
Iodine turns starch blue/black colour;
3
Larger concentration of/more iodine in B/5%;
4
Iodine (diffuses) through the agar;
5
Increasing the concentration of iodine solution speeds up the rate of diffusion;
6
From region of high concentration to region of low concentration; Response

Marks

Candidates must use appropriate specialist terms
throughout to describe and explain the conclusions from
the results using at least 5 of the above points. They use
good spelling, punctuation and grammar and the form and
style are of a high standard.

[5]–[6]

Candidates use some appropriate specialist terms
throughout to describe and explain the conclusions from
the results using at least 3 of the above points. They use
satisfactory spelling, punctuation and grammar and the
form and style are of a satisfactory standard.

[3]–[4]

Candidates make little use of specialist terms throughout
to describe and explain the conclusions from the results
using at least 1 of the above points.
The spelling, punctuation and grammar, form and style are
of a limited standard.

[1]–[2]

Response not worthy of credit.

AVAILABLE
MARKS

[0]
[6]

5

(a) (i)

A – respiration;
B – fossilisation;
C – combustion;

[1]
[1]
[1]

(ii) Photosynthesis;

[1]

(b) (i)

(22 × 100) ÷ 100;
22%;

[2]

(ii) Any two from:
(In city) more factories/more industrial;
More vehicles/cars etc;
More houses;
Less living organisms;
Accept: converse in countryside

7710.01

6

3

[2]

8

6

(a) (Animal) cell which divides/clones/mitosis;
Unspecialised/undifferentiated/later becomes specialised/described;

[2]

(b) Any two from:
Easier to grow/culture;
Easier to extract/obtain/plentiful;
Can develop into different cell types/tissues;
Accept: converse for adult stem cells
Accept: more in placenta/umbilical than in adult bone marrow

[2]

(c) Any three from:
Involves killing/destroying embryo/human life;
Against their religion/playing God;
Human rights of embryo;
Other appropriate response;

[3]

(d) Nervous;
Reject: brain/brain tissue

[1]

7710.01

4

AVAILABLE
MARKS

8

[Turn over

7

(a) (i)

A – bronchus;
B – diaphragm;

[1]
[1]

(ii) Ribs/intercostal muscles/pleural membranes;

[1]

(iii) Pulling rubber sheet/diaphragm/B down;
(Belljar/thorax/chest/lung) volume increases or
Pressure decreases;

[2]

AVAILABLE
MARKS

(b) Any two pairs (feature; appropriate adaptation;) from:
(Many) alveoli; Large surface area;
Close to blood supply/surrounded by capillaries; Maintain (high) diffusion; Thin walls; short diffusion distance;
Moist (lining); Allows gases to dissolve;
Permeable (membranes); Allows gases to diffuse through;
Ventilation; (maintain high)...
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