B 2 Coordination and Control questions and answers 23 minutes 23 marks Page of 36
Q. The photograph shows a girl waiting to cross a road. Lionel Lassman (a) Name two different sense organs she would use to detect when it is safe to cross the road.... 2... (2) Which sense organ contains receptors that help the girl to keep her balance? () (c) (i) Complete the sentence. A car driver automatically brakes if a child dashes out into the road. This is called a... action. () (ii) Draw a ring around the correct answer to complete the sentence. In the nervous system, information passes along cells called effectors neurones synapses. () (Total 5 marks) Page 2 of 36
Q2. A student accidentally touches a sharp object. Her hand is immediately pulled away from the object. The diagram shows the structures involved in this response. (a) Use the correct word or phrase from the diagram to complete each sentence. (i) The stimulus is detected by the... () (ii) Impulses travel to the central nervous system along a cell called a... () (iii) Impulses travel from the central nervous system to the effector along a cell called a... () (iv) The hand is pulled away from the sharp object by the () Where in the body are there cells sensitive to: (i) light... (ii) sound... () () (iii) changes in position?... () (Total 7 marks) Page 3 of 36
Q3. The diagram shows the amount of water lost by an adult in one day. The width of the arrows shows how much water is lost in each way. (a) Work out from the diagram the water loss for urine, skin and lungs and write the correct figures in the spaces on the diagram. When it is hot, much more water is lost from the skin. Which other method of water loss would also change significantly? Explain your answer. (4) (3) (Total 7 marks) Page 4 of 36
Q4. The diagram shows how three hormones, FSH, LH and oestrogen, work together in a woman s body. (a) Name the part of the brain labelled X. () Use information from the diagram and your own knowledge to explain why some oral contraceptive pills contain oestrogen. (3) (Total 4 marks) Page 5 of 36
Q5. The picture shows some birth control (contraceptive) pills for women. These are some facts about using the birth control pills: birth control pills are 99 per cent effective in preventing pregnancy the hormones in the pills have some rare but serious side effects this method of birth control gives no protection against sexually transmitted diseases the hormones in the pills give protection against some women s diseases the woman has to remember to take the pill every day the woman s monthly periods become more regular. Use the information above to answer these questions. (a) Give two advantages of using birth control pills.... 2... (2) Give two disadvantages of using birth control pills.... 2... (2) (Total 4 marks) Page 6 of 36
Q6. (a) Give three receptors which a mouse might use to detect food under natural conditions.... 2... 3... (3) Whilst observing mouse behaviour, a student drops a pen near the mouse s cage. The mouse jumps at the noise. Describe, as fully as you can, the processes by which the mouse responds to the stimulus of the dropped pen. (6) (Total 9 marks) Page 7 of 36
Q7. (a) Describe, as fully as you can, how a human foetus gets rid of the carbon dioxide produced during respiration. (3) The female menstrual cycle is controlled by a number of hormones. The graph below shows the concentrations of four of these hormones at different times during the menstrual cycle. The functions of the four hormones include: FSH stimulates the development of immature cells into eggs in the ovary. LH stimulates the release of the mature egg cell. Oestrogen stimulates production of LH, but inhibits FSH production. Progesterone inhibis production of both LH and FSH. Use this information to explain as fully as you can: Page 8 of 36
(i) how the concentration of oestrogen can affect and control the development and release of an egg during the monthly cycle; (3) (ii) why progesterone continues to be produced throughout pregnancy. (3) (c) Explain, as fully as you can, how one or more of these hormones could be used to treat infertility. (3) Page 9 of 36
(d) A hormone called mifepristone is used in low doses as a female contraceptive. Higher doses can be used to induce an abortion. As a consequence mifepristone is often referred to as the morning-after pill. The use of mifepristone is currently tightly controlled by the medical profession. Evaluate the benefits and problems which might arise from making this hormone more freely available. (4) (Total 6 marks) Q8. A woman wants to have a baby. She has been told that her body is not making and releasing eggs. However she has thousands of cells which could develop into them. A possible treatment is to give her a hormone called FSH. This hormone will start the development of these cells. Once the eggs have developed, explain what causes their release................... (Total 4 marks) Page 0 of 36
Q9. A dog runs across the road in front of a car. The driver slams her foot on the brakes. (i) Explain how the nervous system brings about this response. (4) (ii) Explain why alcohol consumption would affect the driver s response. () (Total 5 marks) Q0. The diagram shows a section through the spinal cord. Page of 36
(a) Coordination of a reflex movement of the arm, in response to the hand touching a hot object, involves three neurones. One of these, the relay neurone, is shown in the diagram. Complete the nerve pathway between the receptor and the muscle on the diagram by drawing and labelling: (i) (ii) the sensory neurone; the motor neurone. (2) The nerve pathway linking the heat receptor in the hand with the arm muscle is about.5 metres in length. It would take the nervous impulse 0.02 seconds to travel this distance along a neurone. However, it takes about 0.5 seconds for the arm to start moving during the reflex response to the heat stimulus. Explain the difference..... (2) (Total 4 marks) Q. Hormones are sometimes used to regulate human reproduction. (a) (i) What is a hormone? () (ii) How are hormones transported around the body? () Page 2 of 36
Describe the benefits and possible problems that may result from the use of hormones to regulate human reproduction. You should refer to fertility drugs and contraceptives in your answer. To gain full marks in this question you should write your ideas in good English. Put them into a sensible order and use the correct scientific words. (4) (Total 6 marks) Q2. Hormones are used in contraceptive pills. (a) Explain how a contraceptive pill works............. (2) Page 3 of 36
Read the information about the trialling of the first contraceptive pill. The Pill was developed by a team of scientists led by Gregory Pincus. The team needed to carry out large scale trials on humans. In the summer of 955, Pincus visited the island of Puerto Rico. Puerto Rico is one of the most densely populated areas in the world. Officials supported birth control as a form of population control. Pincus knew that if he could demonstrate that the poor, uneducated women of Puerto Rico could use the pill correctly then so could women anywhere in the world. The scientists selected a pill with a high dose of hormones to ensure that no pregnancies would occur while test subjects were taking the drug. The Pill was found to be 00% effective when taken properly. But 7% of the women in the study complained of side effects. Pincus ignored these side effects. The women in the trial had been told only that they were taking a drug that prevented pregnancy. They had not been told that the Pill was experimental or that there was a chance of dangerous side effects. Evaluate the methods used by Pincus in trialling the contraceptive pill........................................ (5) (Total 7 marks) Page 4 of 36
Q3. Hormones regulate the functions of many organs. Complete the following sentences. (a) Hormones control the monthly release of an egg from the woman s.... Hormones also control the thickness of the lining of her.... () () (c) Hormones given to women to stimulate the release of eggs are called... drugs. () (Total 3 marks) Q4. The volume of water that the body loses must balance the volume of water that it gains. Tables and 2 show losses and gains of water by the body in one day. (a) (i) Calculate the volume of urine lost by the body. Show clearly how you work out your answer....... Volume of urine lost by the body =... cm 3 (2) Page 5 of 36
(ii) What proportion of water gained by the body comes from food? Put a tick ( ) in the box next to your choice. () One pupil decided to show the figures from Table 2 as a pie chart. Label sections A, B and C of the pie chart. () (c) How does sweating help the body?...... () Page 6 of 36
(d) On a hotter day, the volumes of water lost and gained will be different. What differences will there be? Tick ( ) two answers from the list. More sweat produced More faeces produced More food eaten Less urine produced Less liquid drunk (2) (Total 7 marks) Q5. A person accidentally touches a hot pan. Her hand automatically moves away from the pan. The diagram shows the structures involved in this action. Page 7 of 36
(a) Describe fully how the structures shown in the diagram bring about this reflex action.................................. (6) (i) The nerve pathway in this reflex action is about.5 metres in length. A nerve impulse travels at 75 m s. Use this information to calculate the time taken for this reflex action to occur. Show clearly how you work out your answer....... Time intervals... s (2) (ii) The actual time interval is longer than the interval you have calculated in part (i). Suggest an explanation for the difference....... () (Total 9 marks) Page 8 of 36
Q6. The diagram shows the structures involved in the knee-jerk reflex. When the tendon is struck with the hammer, the receptor is stimulated and the lower leg moves forward. (a) Name the structures labelled A, B and C. A... B... C... (3) How is information passed from structure A to structure B? () (c) What is the effector in this response? () (Total 5 marks) Q7. Reflex actions are rapid and automatic. (a) Name the following structures in a reflex action. (i) The structure that detects the stimulus. () Page 9 of 36
(ii) The neurone that carries impulses to the central nervous system. () (iii) The neurone that carries impulses away from the central nervous system. () (iv) The structure that brings about the response. () Describe what happens at a synapse when an impulse arrives. (2) (c) Some people have a condition in which information from the skin does not reach the brain. Explain why this is dangerous for the person. (2) (Total 8 marks) Page 20 of 36
Q8. Read the information about the trialling of the first contraceptive pill. The Pill was developed by a team of scientists led by Gregory Pincus. The team needed to carry out large scale trials on humans. In the summer of 955, Pincus visited the island of Puerto Rico. Puerto Rico is one of the most densely populated areas in the world. Officials supported birth control as a form of population control. The women in Puerto Rico were mainly poor and uneducated. The scientists selected a pill with a high dose of hormones. The Pill was found to be 00 % effective when taken properly. But 7 % of the women in the study complained of side effects. The women in the trial had been told only that they were taking a drug that prevented pregnancy. They had not been told that the Pill was experimental or that there was a chance of dangerous side effects. Evaluate the issues involved with methods used by Pincus in trialling the contraceptive pill........................................ (Total 6 marks) Page 2 of 36
Q9. Two types of fertility treatment are in-vitro fertilisation (IVF) and in-vitro maturation (IVM). (a) Describe the role of hormones in IVF treatment. (3) Read the passage about fertility treatment. During normal IVF, a woman undergoes several weeks of hormone injections. The treatment can lead to a condition called ovarian hyperstimulation syndrome resulting in a build-up of fluid in the lungs. Very rarely, it can cause death. The syndrome occurs in about % of standard IVF cycles, but in about 0 % of the IVF cycles of some women. An IVF cycle may cost up to 4300. In IVM, hormone treatment lasts for less than 7 days. Eggs are then collected from the ovaries while they are still immature. Each egg is then matured in a laboratory for up to 48 hours before being injected with a single sperm. A few days after fertilisation, the embryos are implanted into the mother s womb. The cost of each IVM cycle is 700. An IVM expert says: In IVM treatment there s a small risk of abnormalities in the sex chromosomes and also of birth deformities and cancer in the babies. These risks are not massive but they are greater than in IVF. Page 22 of 36
Evaluate the use of IVM rather than IVF in treating infertility. Remember to give a conclusion to your evaluation. (4) (Total 7 marks) Page 23 of 36
M. (a) eye / sight / eyesight either order ear / hearing ignore light ear (c) (i) reflex (ii) neurons [5] M2. (a) (i) receptor (ii) (iii) (iv) sensory neurone motor neurone muscle (i) eye(s) allow retina ignore sight (ii) ear(s) ignore hearing do not allow ear drum (iii) ear(s) ignore balance [7] Page 24 of 36
## (a) A > B > C; A + B + C = 2 800; one number correct two numbers correct each for mark 4 urine; less produced; kidneys absorb more water or to maintain (water) balance each for mark 3 [7] M4. (a) pituitary (gland / body) oestrogen inhibits the release of FSH ignore references to LH FSH stimulates follicle development / causes egg to develop or no follicle / egg development if high oestrogen accept growth / maturing / ripening for development no ovulation / no egg release do not accept no egg to be fertilised [4] M5. (a) any two for one mark each answers should relate to the ideas in the list birth control pills are 99 % effective in preventing pregnancy the hormones in the pills give protection against some women s diseases condom (neutral) the woman s monthly periods become more regular 2 Page 25 of 36
any two for one mark each answers should relate to the ideas in the list the hormones in the pills have some rare but serious side effects only 99% effective this method of birth control provides no protection against sexually transmitted disease a woman has to remember to take a pill every day 2 [4] M6. (a) light/eye smell/nose taste/chemical/tongue for mark each 3 6 of e.g. receptors in ear detect sound waves/vibrations impulses/electrical signals to brain brain co-ordinates response impulses sent along nerves to muscles/effectors which contract to bring about response any 6 for mark each 6 [9] M7. (a) moves from foetal blood to mothers blood via placenta for mark each 3 (i) 3 of e.g. rising levels of oestrogen result in an increased LH level when LH level peaks egg release stimulated any 3 for mark each 3 (ii) 3 of e.g. continues to inhibit FSH production and to inhibit LH production so that no eggs are matured or released Because of danger to later conceived fetus if 2 develop in uterus any 3 for mark each 3 Page 26 of 36
(c) 3 of e.g. FSH could stimulate eggs to mature in woman whose own level of FSH too low LH could stimulate egg release where woman s own LH production depressed by oestrogen any 3 for mark each 3 (d) maximum two benefits e.g. prevents unwanted pregnancy when mother s physical health at risk or when mental health at risk or following e.g. rape maximum two problems e.g. involves killing foetus rather than preventing gametes meeting may lead to irresponsible attitude to sexual behaviour reference to ethical/religious attitudes for mark each 4 [6] M8. oestrogen produced gains mark but N.B. sequence important here oestrogen produced by ovary gains 2 marks LH produced gains mark but LH produced by pituitary gains 2 marks LH causes egg release for mark [4] M9. (i) eyes as sense organs/detector/receptors in eye, electrical signals (impulses), to co-ordinator, then to leg muscles/effector for mark each 4 Page 27 of 36
(ii) affects the nervous system and slows down the reactions for mark [5] M0. (a) sensory neurone correctly drawn and labelled from receptor + via dorsal root + cell body in ganglion + synapse to relay neurone motor neurone correctly drawn and labelled to muscle + via ventral root + same shape as relay neurone + synapse with relay neurone OR correct pathways for both neurones given (ie without synapse or cell bodies) and labelled, or correctly drawn but unlabelled = mark for this part) any two from: reference to synapses / gaps between neurones extra time for release / movement of chemical extra time for development of muscle tone / tension 2 [4] Page 28 of 36
M. (a) (i) any one from: chemical messenger chemical / substance released in one part to have effect elsewhere in body (ii) chemical / substance which affects another / target organ / tissues / cells allow chemical from endocrine gland in blood / circulatory system / any named part including plasma extra wrong answer would cancel example not red blood cells Quality of written communication: correct use of at least two relevant scientific terms spelt phonetically e.g. pregnancy, ovulation, FSH, oestrogen, progesterone, ovary, follicle, circulation, thrombosis, feminisation, sperm count, STD Q or Q Page 29 of 36
any three from: Oral contraceptives: (benefit) prevent (unwanted) pregnancy or prevent egg release regulate menstrual cycle / periods (problems) prolonged use may prevent later ovulation / cause infertility named side-effect on female body e.g. circulatory problems / weight gain / nausea / headache / breast cancer / mood swings increased promiscuity / increase in STD s / STI s named side-effect on environment e.g. feminisation of fish or lowered sperm count in human males Fertility drugs: (benefit) can enable woman to have children or to become pregnant or stimulates egg release (problem) multiple births for full marks must score at least one re contraceptives and at least one re fertility drugs if unclear which type of hormone maximum 2 marks from 3 3 [6] M2. (a) inhibits FSH (production / secretion) (therefore) no eggs mature / released if no other marks gained allow mark for no eggs produced or effect of FSH on ovary described references to LH are neutral Page 30 of 36
maximum 4 marks if no conclusion Pros max 2marks from 4 marks e.g. large scale trial gave better results chose uneducated women so that if these women could use it correctly, women elsewhere would be able to cons max 3 marks from 4 marks e.g. used pill with high dose of hormone either so results not valid for general use of hormone or dangerous side effects ignored women not told pill was experimental / pill might have side effects no placebo should have tried a range of doses should have done pre-trial to check for side effects 4 conclusion mark e.g. trials flawed therefore cons outweigh pros accept reverse e.g. trials flawed but pros outweigh cons [7] M3. (a) ovary womb / uterus (c) fertility [3] M4. (a) (i) 400 award 2 marks for correct answer if no working shown 2400 (300 + 600 + 00) or equivalent for mark 2 (ii) Page 3 of 36
A: chemical reactions B: food (c) (d) C: drinking all three required for mark cools / reduces temperature allow maintaining body temperature owtte do not allow regulate unqualified ignore reference to urea numerical references to temperature should be correct more sweat produced less urine produced [7] M5. (a) stimulus / heat detected by temperature receptors in skin impulses travel along sensory neurone to spinal cord / CNS chemical transmission across synapse via relay neurone impulses to muscle / effector via motor neurone muscle / effector contracts, moving the hand away (i) 0.02 s correct answer gains 2 marks if answer incorrect, evidence of.5 / 75 gains mark 2 (ii) impulse slowed down because of time taken for diffusion of the chemical across the synapse [9] Page 32 of 36
M6. (a) A sensory (neurone) ignore nerve B motor (neurone) ignore nerve C spinal cord / central nervous system / grey matter by chemical / substance allow transmitter (c) muscle allow extensor ignore muscle names [5] M7. (a) (i) receptor allow named receptor eg light receptor ignore sensory neurone allow sense organ / named sensory organ eg skin / eye (ii) (iii) (iv) sensory (neurone) allow afferent motor (neurone) allow efferent effector / muscle / gland / named any two from: impulse / information passes from one neurone to another or impulse / information passes across gap chemical / transmitter involved diffusion (across gap) 2 Page 33 of 36
(c) brain / person not aware of pain / stimulus / can t feel allow brain/ person doesn t know / realise / unable to coordinate ignore reflex ignore information possibility of (permanent / serious) damage / eg burning ignore danger [8] M8. argued evaluation large scale trial gave better results chose uneducated women so that if these women could use it correctly, women elsewhere would be able to uneducated women unlikely to give informed consent no placebo used pill with high dose of hormone / should have tried a range of doses / results not valid for other populations women not told pill was experimental / pill might have side effects / should have done pre-trial to check for side effects [6] M9. (a) any three from if oestrogen or progesterone used = max 2 if both oestrogen and progesterone used = max FSH used / given / injected LH used / given / injected FSH causes eggs to mature LH stimulates egg release ignore effects of oestrogen and progesterone 3 Page 34 of 36
max two pros for IVM / it from: allow max two cons for IVF cheaper less hormones used ovarian hyperstimulation or the syndrome less likely allow it s safer for the mother ignore more risks unqualified IVM treatment shorter 2 con for IVM allow max one pro for IVF small risk of abnormal sex chromosomes / birth defects / baby cancer allow more risk to baby ignore more risks unqualified evaluation eg IVM better because less risk to mother outweighs small risk to baby or IVF better because no risk to baby and a small risk to mother must include an appreciation that there are two sides to the argument [7] Page 35 of 36
Page 36 of 36