Homeostasis
Time:
113 minutes
Marks:
108 marks
Name:
________________________
Class:
________________________
Date:
________________________
Comments:
Page 1 of 39
1.
Hormones are involved in controlling the menstrual cycle and fertility.
(a)
(i)
Use the correct answer from the box to complete the sentence.
auxin
follicle stimulating hormone (FSH)
thalidomide
A hormone produced by the pituitary gland is ____________________
(1)
(ii)
Use the correct answer from the box to complete the sentence.
luteinising hormone (LH)
oestrogen
statin
A hormone produced by the ovaries is ___________________________
(1)
(b)
(i)
Why are fertility drugs given to some women?
______________________________________________________________
______________________________________________________________
(1)
(ii)
A doctor injects fertility drugs into a woman. After the injection, the hormones travel
to the woman’s ovaries.
How do the hormones travel to the ovaries?
Draw a ring around the correct answer.
through the bloodstream
through the neurones
through the skin
(1)
(c)
Which two hormones are used in contraceptive pills?
Tick (✔) two boxes.
FSH
oestrogen
LH
progesterone
(2)
(Total 6 marks)
Page 2 of 39
2.
The diagram shows the position of two glands, A and B, in a woman.
(a)
(i)
Name glands A and B.
A ___________________________________
B ___________________________________
(2)
(ii)
Gland A produces the hormone Follicle Stimulating Hormone (FSH).
FSH controls changes in gland B.
How does FSH move from gland A to gland B?
______________________________________________________________
(1)
Page 3 of 39
(b)
(i)
A woman is not able to become pregnant. The woman does not produce mature
eggs. The woman decides to have In Vitro Fertilisation (IVF) treatment.
Which two hormones will help the woman produce and release mature eggs?
Tick ( ) one box.
FSH and Luteinising Hormone (LH)
FSH and oestrogen
Luteinising Hormone (LH) and oestrogen
(1)
(ii)
Giving these hormones to the woman helps her to produce several mature eggs.
Doctors collect the mature eggs from the woman in an operation.
Describe how the mature eggs are used in IVF treatment so that the woman may
become pregnant.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(3)
(iii)
IVF clinics have been set a target to reduce multiple births.
At least 76% of IVF treatments should result in single babies and
a maximum of 24% of treatments should result in multiple births.
Suggest one reason why the clinics have been set this target to reduce multiple
births.
______________________________________________________________
______________________________________________________________
(1)
Page 4 of 39
(c)
Two clinics, R and S, used IVF treatment on women in 2007. Doctors at each clinic used
the results of the treatments to predict the success rate of treatments in 2008.
The table shows the information.
Total number of IVF
treatments in 2007
Number of IVF
treatments resulting in
pregnancy in 2007
Predicted percentage
success rate in 2008
Clinic R
1004
200
18–23
Clinic S
98
20
3–56
(i)
Compare the success rates of the two clinics in 2007.
______________________________________________________________
______________________________________________________________
(1)
(ii)
The range of the predicted success rate in 2008 for clinic R is much smaller than the
range of the predicted success rate for clinic S.
Suggest why.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(2)
(Total 11 marks)
3.
This question is about hormones.
(a)
(i)
Hormones carry messages.
What type of messenger is a hormone?
Draw a ring around the correct answer.
chemical
electrical
environmental
(1)
Page 5 of 39
(ii)
Which part of the brain secretes hormones?
Draw a ring around the correct answer.
cerebellum
medulla
pituitary gland
(1)
(b)
Figure 1 shows the level of a pregnancy hormone over a 40-week pregnancy.
This hormone can be detected in a pregnancy test.
Figure 1
A woman takes a pregnancy test.
In which week of pregnancy is the test most likely to give a positive result?
Use information from Figure 1.
Write the correct answer in the box.
(1)
Page 6 of 39
(c)
Figure 2 shows the levels of three other hormones during pregnancy.
The baby is usually born at about 40 weeks.
Figure 2
Adaptation by kind permission of Biozone International
(i)
Describe the patterns in the levels of oestrogen and progesterone from 0 to 36
weeks.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(4)
(ii)
Which hormone is likely to stimulate contractions of the uterus (womb) when the
baby is born?
Use information from Figure 2 to give a reason for your answer.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(2)
(Total 9 marks)
Page 7 of 39
4.
(a)
Which organ of the human body produces egg cells?
Draw a ring around the correct answer.
liver
ovary
testis
(1)
(b)
An egg joins with a sperm and develops into an embryo.
How many chromosomes are there in each cell of a human embryo?
Draw a ring around the correct answer.
23
46
48
(1)
(c)
Some women find it difficult to have a baby. A doctor may suggest that these women
should use In Vitro Fertilisation (IVF) to help them have a baby.
Table 1 shows how successful IVF was for women of different ages at one clinic.
Table 1
Age of women in
years
(i)
Percentage of women
who had a baby
<35
35
35–37
31
38–39
25
40–42
32
43–44
7
>44
0
A student thought that the result for women aged 40–42 was anomalous.
Suggest why the student thought this result was anomalous.
______________________________________________________________
______________________________________________________________
(1)
Page 8 of 39
(ii)
Describe the general trend in the results in Table 1.
You should ignore the anomalous result.
______________________________________________________________
______________________________________________________________
(1)
(d)
Some babies are born with a faulty chromosome.
Scientists investigated whether the chance of having a baby with a faulty chromosome is
also related to the age of the woman.
Table 2 shows the scientists’ results.
Table 2
Age of women in Number of women per 1000 who had a
years
baby with a faulty chromosome
(i)
25
2.0
30
2.6
35
6.1
40
19.6
45
66.0
A 45-year-old woman is more likely than a 25-year-old woman to have a baby with a
faulty chromosome.
How many times more likely?
______________________________________________________________
______________________________________________________________
Answer = _____________________ times
(2)
Page 9 of 39
(ii)
Suggest two reasons why many fertility clinics will not accept women over 40 years
of age for IVF treatment.
Use information from Table 1 and Table 2 in your answer.
1. ____________________________________________________________
______________________________________________________________
2. ____________________________________________________________
______________________________________________________________
(2)
(Total 8 marks)
5.
Many human actions are reflexes.
(a)
Which two of the following are examples of reflex actions?
Tick two boxes.
Jumping in the air to catch a ball
Raising a hand to protect the eyes in bright light
Releasing saliva when food enters the mouth
Running away from danger
Withdrawing the hand from a sharp object
(2)
Figure 1 shows how the size of the pupil of the human eye can change by reflex action.
Figure 1
Page 10 of 39
(b)
Name one stimulus that would cause the pupil to change in size from A to B, as shown in
Figure 1.
____________________________________
(1)
(c)
Structure Q causes the change in size of the pupil.
Name structure Q.
____________________________________
(1)
(d)
Describe how structure Q causes the change in the size of the pupil from A to B.
___________________________________________________________________
___________________________________________________________________
(1)
(e)
Figure 2 shows some structures involved in the coordination of a reflex action.
Figure 2
Page 11 of 39
Describe how the structures shown in Figure 2 help to coordinate a reflex action.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(6)
(Total 11 marks)
6.
Reflex actions are coordinated by the nervous system.
(a)
What is meant by the term ‘reflex action’?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
Page 12 of 39
(b)
A woman’s hand accidentally touches a hot object.
The woman moves her hand away rapidly.
Describe how the woman’s nervous system coordinates the reflex action.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(6)
(c)
The endocrine system coordinates many internal functions of the body.
Give three ways coordination by the endocrine system is different from coordination by the
nervous system.
1 ________________________________________________________________
___________________________________________________________________
2 ________________________________________________________________
___________________________________________________________________
3 ________________________________________________________________
___________________________________________________________________
(3)
Page 13 of 39
(d)
Describe how hormones control the menstrual cycle.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(5)
(Total 16 marks)
7.
The graph below shows some changes that occur during the menstrual cycle.
Page 14 of 39
(a)
The graph above shows that the lining of the uterus thickens between days 7 and 27.
What is the purpose of thickening the lining of the uterus?
Tick one box.
To allow implantation of the embryo
To break down waste
To prevent sperm reaching the egg
(1)
(b)
Which hormone causes thickening of the lining of the uterus?
Tick one box.
Auxin
Oestrogen
Testosterone
(1)
(c)
On which day is fertilisation most likely to occur?
Use information from the graph above.
___________________________________________________________________
(1)
Page 15 of 39
Contraception can be used to lower the chance of pregnancy.
(d)
Draw one line from each method of contraception to how the method works.
Method of contraception
How the method works
Barrier to prevent sperm
reaching the egg
Contraceptive pill
Contains hormones to stop
eggs maturing
Diaphragm
Kills
sperm
Spermicidal cream
Slows down sperm
production
(3)
(e)
The table below gives information about some different methods of contraception.
Number of pregnancies per
100 women in one year
Possible Side effects
Diaphragm and
spermicidal cream
8
Usually none, but can cause
bladder infection in some
women
Condom
2
None
1
Mood swings, headaches,
high blood pressure, blood
clots, breast cancer
Method
Contraceptive pill
Page 16 of 39
A man and a woman decide to use the condom as their method of contraception.
Suggest three reasons for this decision.
Use information from the table above and your own knowledge.
1. _________________________________________________________________
___________________________________________________________________
2. _________________________________________________________________
___________________________________________________________________
3. _________________________________________________________________
___________________________________________________________________
(3)
(Total 9 marks)
8.
It is important to keep the blood glucose concentration within narrow limits.
(a)
A person eats a meal containing a lot of carbohydrate. This causes an increase in the
person’s blood glucose concentration.
Explain how the hormones insulin and glucagon control the person’s blood glucose
concentration after the meal.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(5)
Page 17 of 39
(b)
The body cells of a person with Type 2 diabetes do not respond to insulin.
A person with Type 2 diabetes often has a higher blood insulin concentration than a
non-diabetic person.
Explain why.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(3)
Metformin is a drug used for treating people who have Type 2 diabetes.
Scientists investigated the effects of metformin and two other drugs, A and B.
The scientists wanted to see how the drugs affected the blood glucose concentrations of 220
people with Type 2 diabetes.
This is the method used.
1. Put the 220 people into five groups.
2. Treat each group with a different drug or combination of drugs for several weeks.
3. Give each person a meal high in carbohydrate.
4. Measure the blood glucose concentration of each person 30 minutes after the meal and
again 3 hours after the meal.
(c)
Suggest three variables that the scientists should have controlled in the investigation.
1 _________________________________________________________________
___________________________________________________________________
2 _________________________________________________________________
___________________________________________________________________
3 _________________________________________________________________
___________________________________________________________________
(3)
Page 18 of 39
The scientists recorded their results as a mean value for each group.
The scientists calculated the ‘standard deviation’ for each group’s result.
Standard deviation is a measure of the spread of the individual results above or below (±) the
mean value.
The scientists gave each group’s result as:
mean ± standard deviation
The larger the standard deviation, the greater is the spread of results around the mean.
(d)
Which of the results is the most precise?
Tick (✓
✓) one box.
Mean = 171.6 ± 16.3
Mean = 177.2 ± 15.4
Mean = 182.5 ± 18.2
Mean = 205.2 ± 19.4
(1)
Page 19 of 39
The following table and the figure show the scientists’ results.
Drugs used
Number of people
Mean blood glucose
concentration 30
minutes after the meal
in mg/100 cm3 ±
standard deviation
Metformin Metformin
+A
+B
Metformin
A
B
60
40
25
65
30
177.2
± 15.4
182.5
± 18.2
171.6
± 16.3
205.2
± 19.4
206.5
± 19.6
Page 20 of 39
In the table and the figure some standard deviations of results overlap.
•
An overlap of standard deviations shows the difference between the means is not
significant.
•
No overlap of standard deviations shows a significant difference between the means.
(e)
A student looked at the scientists’ method and the results in the table and figure above.
The student stated:
‘Metformin works better when used with other drugs.’
Evaluate the student’s statement.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(6)
(Total 18 marks)
Page 21 of 39
9.
The nervous system allows a person to detect stimuli.
(a)
Draw one line from each stimulus to the sense organ that detects the stimulus.
(2)
Moving a hand away from a hot object is an example of a reflex action.
(b)
What is a reflex action?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(c)
A muscle in the arm moves the hand away from the hot object.
How does the arm muscle do this?
Tick (✓
✓) one box.
The muscle contracts.
The muscle expands.
The muscle relaxes.
The muscle shrinks.
(1)
Page 22 of 39
Two students investigated the effect of drinking coffee on reaction time.
This is the method used.
1. Student A holds a metre rule just above student B’s hand, as shown in Figure 1.
2. Student A lets go of the metre rule.
3. Student B catches the metre rule as quickly as possible.
4. Student A writes down the reading from the scale on the metre rule.
5. Students A and B repeat steps 1-4 another four times.
6. Student B then drinks a cup of coffee.
7. After 15 minutes, students A and B repeat steps 1-5.
Figure 1
The table below shows some of the results.
Test
1
2
3
4
5
Reading from scale on metre rule in cm
Before drinking coffee
After drinking coffee
18
10
21
14
15
12
19
Page 23 of 39
Figure 2 shows the results after drinking the coffee for tests 3, 4 and 5
Figure 2
(d)
Complete the table.
Use results from Figure 2.
(2)
The students made the following conclusion:
‘Drinking coffee speeds up reactions.’
(e)
Give evidence from the table above to support the students’ conclusion.
___________________________________________________________________
___________________________________________________________________
(1)
(f)
The students’ conclusion may not be valid.
Suggest two improvements the students could make to their method.
1 _________________________________________________________________
___________________________________________________________________
2 _________________________________________________________________
___________________________________________________________________
(2)
(Total 10 marks)
Page 24 of 39
10.
Many internal processes of the human body are controlled by hormones.
Hormones are produced by glands.
Figure 1 shows glands in a woman’s body.
Figure 1
(a)
Which gland is the pituitary gland?
Tick (✓
✓) one box.
A
B
C
D
(1)
(b)
Which gland is the pancreas?
Tick (✓
✓) one box.
A
B
C
D
(1)
The hormone insulin helps to decrease the blood glucose concentration.
Insulin causes its target organs to take in glucose from the blood.
Page 25 of 39
(c)
Which of the following is a target organ for insulin?
Tick (✓
✓) one box.
Bladder
Heart
Liver
(1)
(d)
The glucose is stored as an insoluble substance.
What is the insoluble storage substance that is formed from glucose?
Tick (✓
✓) one box.
Glycogen
Protein
Urea
(1)
Page 26 of 39
Scientists investigated the effect of a glucose drink on the concentration of glucose in a person’s
blood.
This is the method used.
1.
Take a small sample of blood from the person.
2.
Measure the concentration of glucose in the person’s blood.
3.
Give the person a drink containing 50 grams of glucose.
4.
Measure the concentration of glucose in the person’s blood at intervals.
5.
Calculate the change in blood glucose concentration from the starting value.
Figure 2 shows the results.
Figure 2
Figure 2 shows the change in blood glucose concentration.
(e)
At the start of the investigation, the blood glucose concentration was 5 mmol/dm3.
Calculate the highest blood glucose concentration during the investigation.
Use information from Figure 2 in your answer.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
Highest blood glucose concentration = _______________ mmol/dm3
(2)
Page 27 of 39
(f)
What is the time taken for the blood glucose concentration to decrease from its highest
value back to the starting value?
Use data from Figure 2 in your answer.
___________________________________________________________________
Time taken = _______________ minutes
(1)
(g)
Why can you not be certain that your answer to part (f) is accurate?
___________________________________________________________________
___________________________________________________________________
(1)
(h)
Figure 2 above shows the results for a person who does not have Type 2 diabetes.
Sketch a line on Figure 2 to show the results you would expect for a person who has Type
2 diabetes.
(2)
(Total 10 marks)
Page 28 of 39
Mark schemes
1.
(a)
(i)
follicle stimulating hormone / FSH
1
(ii)
oestrogen
1
(b)
(i)
any one from:
•
to help them have a baby / get pregnant
ignore to make them fertile
•
to stimulate egg production / release / maturation
•
own levels of FSH / LH / hormone (too) low
allow to increase hormone / FSH / LH levels
do not allow to increase oestrogen levels
1
(ii)
through the bloodstream
1
(c)
oestrogen
1
progesterone
1
[6]
2.
(a)
(i)
A – pituitary
allow hypothalamus
1
B – ovary / ovaries
1
(ii)
in blood (stream)
accept in plasma
ignore dissolved
1
(b)
(i)
FSH and Luteinising Hormone (LH)
1
(ii)
fertilised
OR
reference to sperm
1
form embryos / ball of cells or cell division
1
(embryo) inserted into mother’s womb / uterus
allow (fertilised egg) is inserted into mother’s womb / uterus
1
Page 29 of 39
(iii)
any one from:
•
multiple births lead to low birth weight
•
multiple births cause possible harm to mother / fetus / embryo / baby /
miscarriages
allow premature
ignore reference to cost / ethics / population
1
(c)
(i)
any one from:
•
almost identical
allow S (slightly) more successful
•
both approximately 20%
1
(ii)
larger numbers (in clinic R) (in 2007)
allow only 98 (in S) (compared to 1004 (in R))
1
results likely to be more repeatable (in 2008)
allow more reliable
do not accept more reproducible / accurate / precise
1
[11]
3.
(a)
(i)
chemical
1
(ii)
pituitary gland
1
(b)
8
allow 9 or 10
1
Page 30 of 39
(c)
(i)
any four from:
•
progesterone starts being produced at 4 weeks / no progesterone before
4 weeks
•
and then / from 4 weeks increases
•
oestrogen at constant / low level (from 0) to 20 weeks
•
and then / from 20 weeks increases
•
from 20 − 36 weeks level of O rises more steeply than that of P
or
•
P is always higher than 0 from 6 to 36 weeks
if no other marks awarded, allow progesterone and oestrogen both
increase / rise for 1 mark.
4
(ii)
oxytocin
1
level of oxytocin increases just before birth
1
[9]
4.
(a)
ovary
1
(b)
46
1
(c)
(i)
does not fit the pattern
or
it is higher than the 3rd value / it should be lower than the 3rd value / it should be
between the 3rd and 5th values
do not allow use of incorrect figures
1
(ii)
As age increases % of women (having a baby) decreases
1
(d)
(i)
33
allow 1 mark for
if no answer / wrong answer
2
(ii)
low success rate
1
more likely to have a baby with health problems / abnormalities / a faulty
chromosome
1
[8]
5.
(a)
releasing saliva when food enters the mouth
1
withdrawing the hand from a sharp object
1
Page 31 of 39
(b)
bright light
allow described method of increasing light
ignore light unqualified
allow correctly named drug e.g. morphine / heroin
1
(c)
iris
1
(d)
muscle contraction
allow muscles shorten
ignore radial / circular
ignore muscles relax / constrict
do not accept muscles expand
do not accept ciliary muscle contracts
1
(e)
Level 2: Scientifically relevant facts, events or processes are identified and given in
detail to form an accurate account.
4−6
Level 1: Facts, events or processes are identified and simply stated but their
relevance is not clear.
1−3
No relevant content
0
Indicative content
•
•
•
receptor detects stimulus
e.g. receptor detects pressure
receptor generates impulses / electrical signals
•
•
•
•
•
•
•
•
neurones conduct impulses / electrical signals
neurone A conducts impulses to spinal cord
neurone A = sensory neurone
synapse between neurones
chemical (/ neurotransmitter) crosses synapse
chemical stimulates impulse(s) in neurone B
neurone B = relay neurone
neurone C = motor neurone
•
•
•
effector carries out response
e.g. muscles of the arm / leg contract
muscles contract or gland secretes chemicals
to access level 2, candidates need to consider, in terms of the indicative content, the
receptor, the neurones and the effector in the correct sequence
[11]
Page 32 of 39
6.
(a)
response / reaction
ignore examples
ignore action
1
automatic or no thinking or not conscious or involuntary
ignore reference to brain
ignore quick
1
(b)
receptor (in skin of finger / hand) detects stimulus / temperature change
allow receptor detects heat ignore pain
1
(electrical) impulses pass along neurones
allow electrical signals pass
along nerve cells
ignore messages
1
(impulses pass from) sensory to relay to motor neurones
1
synapse between neurones where chemical crosses gap
allow neurotransmitter / acetylcholine for chemical
allow by diffusion
1
(synapses) in spinal cord / CNS
ignore brain
1
muscle contraction (to pull hand away)
or effector is a muscle
1
(c)
coordination by endocrine system is:
allow converse points if clearly indicating nervous
co-ordination answers must be comparative
slower
1
longer-lasting
1
(chemical / hormone) via blood instead of electrical / impulse / neurones
1
Page 33 of 39
(d)
FSH (release from pituitary) stimulates maturation of egg / ovum / follicle
ignore reference to days of menstrual cycle
allow FSH stimulates development / growth of egg
1
oestrogen (release from ovary) inhibits FSH production and stimulates LH production
1
LH (release from pituitary) stimulates ovulation
allow LH stimulates release of egg
1
progesterone (release from ovary) inhibits FSH and LH production
allow (release from corpus luteum)
1
oestrogen and progesterone maintain the uterus lining
allow oestrogen and progesterone build up the uterus
lining
1
[16]
7.
(a)
to allow implantation of the embryo
1
(b)
oestrogen
1
(c)
13 / 14 / 15 / 16
allow any number in range 13 to 16
allow any range within these values e.g. 14−16
1
(d)
extra line from a method cancels the mark
1
1
1
Page 34 of 39
(e)
more reliable than diaphragm / spermicidal cream
allow fewer pregnancies than diaphragm / spermicidal
cream
1
low chance of pregnancy
allow only 1 more pregnancy than the pill (per 100
women per year)
allow almost as good as the pill
allow reference to one named example
1
no side effects
allow easy to get / buy
allow easy to use
allow prevent / reduce spread of STDs / gonorrhoea /
HIV
ignore cost
1
[9]
8.
(a)
ignore incorrect organ secreting insulin / glucagon
(blood glucose increases after meal causing) insulin secretion
allow (blood glucose increases after meal causing)
insulin increase
1
insulin causes glucose to enter cells / liver / muscles
1
(insulin causes) glucose conversion to glycogen
1
allow glucose converted to glycogen in cells / liver /
muscles for 2 marks
(so) blood glucose decreases causing glucagon secretion
allow increase in glucagon when blood glucose is low
1
glucagon causes glycogen to be converted to glucose
1
Page 35 of 39
(b)
cells / liver / muscles absorb less glucose
allow cells / liver / muscles convert less glucose to
glycogen
do not accept no absorption / conversion of glucose
1
(so) glucose concentration in blood remains high
allow (so) glucose concentration in blood does not
decrease
1
(high blood glucose stimulates / causes) pancreas to release more insulin
allow more insulin is released from pancreas to ‘try’ to
reduce blood glucose
1
(c)
any three from:
•
age
•
height and mass
allow BMI
•
proportion of males and females or group size
allow sex of the participants
•
(same) severity of diabetes
•
(same) activity (during investigation)
•
(same) type of meal
•
dose of drug
•
(similar) blood glucose concentrations at start
allow how much / type of food / drink consumed before
•
other health conditions or other drugs being taken
allow may not have followed drug-taking regime
beforehand
3
(d)
Mean = 177.2 + 15.4
1
(e)
Level 3: A judgement, strongly linked and logically supported by a
sufficient range of correct reasons, is given.
5–6
Level 2: Some logically linked reasons are given. There may also
be a simple judgement.
3–4
Level 1: Relevant points are made. They are not logically linked.
1–2
No relevant content
0
Page 36 of 39
Indicative content
Pro:
•
Met + A gives larger (%) reduction (in blood glucose) than Met alone
•
so statement is supported
•
•
Met + B gives larger (%) reduction (in blood glucose) than Met alone
so statement is supported
•
•
Met + A SD does not overlap with Met SD
so difference is significant
Con:
•
Met + B SD overlaps with Met SD
•
so difference is not significant
•
difference in results could be due to chance
•
•
•
•
---------------------------------------------------------------------------------------------number of people used is not very large
number of people in each group is different
so may not be representative or may not be repeatable / reproducible
so anomalies will have a bigger impact on smaller groups
•
•
•
30 minute / starting levels of blood glucose are different
all 30 minute / starting levels are higher in the 2-drug trial
so may cause different % reductions
•
•
•
no information about control variables or named e.g.
concentration of drugs not given / may differ
so results may not be valid
for level 3 an inclusion of a discussion of significance is required
[18]
9.
(a)
additional lines from a stimulus negates the mark for
that stimulus
2
Page 37 of 39
(b)
any two from:
1
•
•
fast / rapid
protect (from danger / harm)
•
a response / a reaction
1
•
ignore ‘action’
automatic / involuntary or not under conscious control
allow not coordinated by conscious part of the brain
or
allow does not involve thought / thinking
ignore not coordinated by the brain
(c)
the muscle contracts
1
(d)
(10)
(14)
8
11
13
in this order
all 3 correct = 2 marks
2 correct = 1 mark
0 or 1 correct = 0 mark
2
(e)
(after drinking coffee) ruler falls less far (before being caught)
allow mean before = 17 and mean after = 11(.2)
or mean after is only 11(.2)
allow (ruler is) caught more quickly
1
(f)
any two from:
•
more repeats
•
test more students
•
use ruler with more precise scale – e.g. mm scale
ignore accurate
•
drop from same height (above the hand)
•
make sure student B’s hand is stationary
•
same distance between finger(s) and thumb
allow alternative method – e.g. use of computer to
measure reaction time
2
[10]
10.
(a)
A
1
(b)
D
1
(c)
liver
1
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(d)
glycogen
1
(e)
2.6
allow answers in the range 2.5 to 2.7
1
7.6 (mmol/dm3)
allow a correctly calculated value using student’s value
from graph + 5
1
(f)
30 (minutes)
allow ½-hour or 0.5 hour
1
(g)
points too far apart
or
no reading between 30 and 50 mins
allow no reading at 40 mins
or
points joined by straight lines
or
values could have fallen to zero change before 50 mins
allow not a curve of best fit
1
(h)
higher values of y than given line
1
returning to(wards) zero change later than given line
1
[10]
Page 39 of 39