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2H Transport in Animals & PantsTime: 1 hour 48 minutesTotal marks available: 108Total marks achieved: Q1.The diagrams show sections through an artery and a vein.2103120154115Use the information in the diagrams and your own knowledge to give three ways in which the structure of an artery differs from the structure of a vein.1(3).................................................................................................................................................................................................................................................................................................................................................2.................................................................................................................................................................................................................................................................................................................................................3.................................................................................................................................................................................................................................................................................................................................................Lack of movement by sitting still for long periods of time makes blood flow very slowly in a vein. Blood that flows slowly is more likely to clot than blood thatflows normally. This problem is known as deep vein thrombosis (DVT). In DVT, the clot usually occurs in a leg vein as shown in the diagram.DVT is dangerous because sometimes part of the clot breaks off and travels to the lung, blocking small blood vessels and causing death.Suggest why blood flow in a leg vein is slow when there is lack of movement.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Name the blood cells responsible for transporting oxygen...............................................................................................................................................Suggest why a clot that blocks the small blood vessels in the lungs can cause death...............................................................................................................................................(2)(1)(2)(Total for question = 8 marks)Q2.Read the passage below. Use the information in the passage and your own knowledge to answer the questions that follow.Artificial heart pump gives life to dying patientsName two of the blood vessels that carry blood away from the heart.............................................................................................................................................................................................................................................................................................Suggest why the batteries for the heart pump are placed outside the body (lines 12 and 13).............................................................................................................................................................................................................................................................................................Describe how the blood in the left side of the heart differs from the blood in the right side of the heart.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Explain why the patient might need to change the speed of the pump (line 22).........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Explain why some patients are 'not able to have a transplant' (line 28).............................................................................................................................................................................................................................................................................................(f ) Suggest what is meant by the term intraventricular (line 29)...............................................................................................................................................Suggest two advantages of using the new artificial heart pump compared to previous artificial heart pumps.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(2)(1)(2)(2)(1)(1)(2)(Total for question = 11 marks)Q3.The immune system responds to infection using white blood cells. A phagocyte is one type of white blood cell.(i) Draw and label a phagocyte.(3)Give one way that the structure of this cell differs from a red blood cell.............................................................................................................................................................................................................................................................................................Describe how white blood cells are used by the body to defend against infection.......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(1)(5)(Total for question = 9 marks)Q4.The box shows the names of three blood vessels.The table gives information about these blood plete the table by writing the name of the correct blood vessel in each empty box.(2)(i) Which of these blood vessels carries blood containing the most oxygen?..............................................................................................................................................Which of these blood vessels carries blood at the lowest pressure?..............................................................................................................................................Which of these blood vessels is most suited for gas exchange?Explain your answer.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(1)(1)(2)(Total for question = 6 marks)Q5.An investigation was carried out to find out the effect of fear on human heart rate.Ten students measured their heart rate under normal conditions. The students were then given a fright and asked to measure their heart rate again.1159510253311The table shows their results.(i) Identify the student whose result was anomalous...............................................................................................................................................Describe and explain the results of this investigation.......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................State, with a reason, whether the results of this investigation are reliable.............................................................................................................................................................................................................................................................................................The diagram shows the human heart with four chambers and four blood vessels labelled A to H.(1)(2)(1)Complete the table by writing in the label letter that matches the description of the structure.The first one has been done for you.(4)(Total for question = 8 marks)Q6.The diagram shows a mammal heart with glass tubes, X and Y, securely attached to the vena cava and the pulmonary artery. Water was poured into tube X, and rose up tube Y until both tubes were filled to the level shown.1722120230331When water was poured into tube X, two chambers in the heart were filled with water.Name these two chambers.(2)1 ........................................................................................................................................................................................................2 ........................................................................................................................................................................................................The ventricles were squeezed once by hand.Suggest what would happen to the level of water in tube X and in tube Y when the ventricles were squeezed.............................................................................................................................................................................................................................................................................................Explain why no water came out of the aorta when the ventricles were squeezed.............................................................................................................................................................................................................................................................................................(1)(1)(Total for question = 4 marks)Q7.Doctors sometimes give antibiotics to very ill patients. The passage below describes the plete the sentences in the passage by writing a suitable word or words on each dotted line.Antibiotic solution is given to the patient through a tube. The tube is connected toa vein in the arm of the patient, using a needle. It is connected to a vein rather than an artery because veins have a lower .............................................................. than arteries. The antibiotic travels to the heart in the largest vein in the body called the.............................................................. .It enters a chamber called the right atrium, and passes to the right.............................................................. .before being pumped to the lungs in the .............................................................. artery. The antibiotic returns to the heart and eventually leaves the heart in the aorta,the largest .............................................................. in the body. The antibiotic is then carried to the tissues where it leaves the smallest blood vessels called.............................................................. .The antibiotic then kills pathogens called .............................................................. that were responsible for the patient being very ill.(Total for question = 7 marks)Q8.The table gives statements about blood cells. Some apply to red blood cells and some to white blood plete the table by using a tick or a cross to show if each statement applies to red blood cells or to white blood cells. The first statement has been done for you.(5)Some athletes preparing for a long distance race train at high altitude for several weeks. The availability of oxygen at high altitude is lower so the body respondsby increasing the number of red blood cells. The number of red blood cells remains high when the athletes return to lower altitude to compete.Explain how having more red blood cells is an advantage to athletes who take part in long distance races.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................A 100 m sprint race takes less than 10 seconds to complete.Suggest why sprint athletes gain no advantage from training at altitude.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(4)(2)..............................................................................................................................................(Total for question = 11 marks)Q9.Multicellular organisms have a transport system for nutrients and waste products. In humans this transport system involves the blood.The table names some components of blood. Complete the table by giving the function of each component and its cell type.(4)Suggest the consequence of having too few platelets in the blood...........................................................................................................................................................................................................................................................................................................................................................................................................................................Vaccination causes the body to produce memory cells.Describe the advantages to the human body of producing memory cells.....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(2)(2)(Total for question = 8 marks)Q10.Two potted plants, A and B, have the same surface area of leaves. They each have a mass of300.0 g.The mass of each potted plant was measured on the balance as shown.1437005154781The plants were placed in different environmental conditions for 12 hours and their masses were measured again.The mass of both plants was less after 12 hours because of transpiration.What is meant by the term transpiration?........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Suggest why a polythene bag was put around the pot of soil.............................................................................................................................................................................................................................................................................................(2)(1)Explain why plant B lost more mass than plant A.................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(4)(Total for question = 7 marks)Q11.Bethany wanted to compare the mass of water lost from the upper surface and the lower surface of a leaf.She set up an experiment using four leaves from the same species of tree. She estimated the surface area of each leaf by drawing around its outline on squared paper as shown in the diagram.Estimate the total surface area of this leaf in cm2.(2)........................................................... cm2She applied a thin layer of petroleum jelly to the leaves as described below.Leaf A no surface coveredLeaf B lower surface covered Leaf C upper surface coveredLeaf D upper and lower surfaces covered1311910604491She then carefully weighed the leaves and recorded their mass. She hung the leaves by their stalks from a wire as shown. She left the leaves for 6 hours and then carefully weighed them again.Leaf C had a lower surface area of 24 cm2 and lost 0.2 g in 6 hours.Calculate the loss of mass from leaf C in g per cm2 in 1 hour.(2)Answer ........................................................... g per cm2 in 1 hourIdentify the independent variable in this experiment...............................................................................................................................................Identify the dependent variable in this experiment...............................................................................................................................................State one variable that Bethany should control in this experiment...............................................................................................................................................(f ) (i) Complete the table to show the order in which the leaves A to D are most likely to lose mass.(1)(1)(1)(2)(ii) Give an explanation for your answer.....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(3)(Total for question = 12 marks)Q12.Cactus plants are adapted to survive in hot, dry conditions. They have shallow, widespread root systems, the ability to store water in their stems, spines for shade, a waxy coating and no leaves.2259964155418Explain how having no leaves can help a cactus plant reduce water loss.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Suggest how a shallow, widespread root system would help a cactus to survive in desert environments.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Other than shading, suggest one advantage to cactus plants of having spines.............................................................................................................................................................................................................................................................................................(2)(2)(1)(Total for question = 5 marks)Q13.Steven wanted to measure the rate of water loss from a leafy shoot. He set up this apparatus in normal laboratory conditions.2546399231605Name the apparatus Steven used...............................................................................................................................................Name the process by which a plant loses water...............................................................................................................................................Describe how Steven should set up the apparatus and how he should then use it to estimate the rate of water loss from the leafy shoot...................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................(1)(1)(4)..........................................................................................................................................................................................................................................................................................................................................................................................................................................Steven carried out three further experiments. He used the same plant, but changed one condition in each experiment.The table shows the percentage change in rate of water loss for each condition when compared to Steven's original experiment.Explain the change in water loss whenwind was increased.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................light intensity was reduced...........................................................................................................................................................................................................................................................................................................................................................................................................................................half of the leaves were removed.........................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................Suggest how Steven could increase the wind around the leafy shoot.............................................................................................................................................................................................................................................................................................(2)(1)(2)(1)(Total for question = 12 marks)Q1.In part (a) students were given a cross section diagram of an artery and a vein and asked to give three differences. Most could do this but some got the answers the wrong way round or their language lacked precision as they described wider or bigger without specifying which tissue.Some gave differences in function rather than structure. In part (b) information on DVT and clot formation was given and in part (i) students had to suggest why blood flow in a vein is slow when there is lack of movement. Only the best students described how lack of muscle contraction would not squeeze the blood back to the heart. Almost all answers were correct in (ii) for the cells that transport oxygen. In part (iii) most students were able to suggest why a clot that blocks the small vessels in the lungs could cause death. The weakest students wrote about oxygen being taken to the lungs.Q2.Most candidates were able to access the questions based on the comprehension with ease. Part (a) required recall of the names of two blood vessels and only the weaker candidates failed to name the aorta and pulmonary artery correctly.Candidates clearly understood the reasons why the batteries are placed outside the body. Most correct answers made reference to the fact that they can easily be replaced or recharged. In part (c), a surprising number of candidates made reference to the left side of the heart containing blood that was deoxygenated and at lower pressure, showing confusion about heart anatomy. A pleasing number of candidates appreciated that exercise requires increased oxygen supply to respiring muscle cells and that changing the speed of the pump would facilitate this need. In part (e), the most common correct responses made reference to the shortage of hearts or problems associated with tissue compatibility. References to ill health, age or cost issues were not credited. This comprehension required students to understand a term they may not have seen before. Credit was given for any reference to the device being in the ventricle.Candidates who quoted that the device was in the heart or between the ventricles were not credited.Q3.Part (a)(i) required students to draw a phagocyte. Most scored 2 or 3 marks with the best drawings showing and labelling a cell membrane, cytoplasm a lobed nucleus. Some labelled a cell wall and others drew a red blood cell. In part (ii) almost all answers gave a correct difference between this cell and ared blood cell. In part (b) the many students who had revised the material gained 5 marks by describing how white blood cells defend the body against infection.Q4.This question provided data on the lumen and vessel wall thickness of three blood vessels. Almost all candidates could recognise the capillary as the smallest lumen and thinnest walls but often failed to match the aorta and vena cava. Most could identify the aorta as carrying blood with most oxygen and the vena cava as carrying blood with the least pressure. Almost all could identify the capillary asthe vessel most suited to gas exchange but not all could explain the reason in terms of thin walls, short diffusion distance.Q5.This question explored aspects of the human heart and was answered well by most candidates. An anomalous result is one that does not fit the pattern and in part (a) (i) the answer the examiners rewarded was student 8. This was the only student who did not show an increase in heart rate having been frightened. Part(ii) posed little difficulty with most candidates appreciating that the heart rate increases when frightened and almost 50% read the question carefully to offer adrenaline release as the explanation. Answers to part (iii) showed that only the best candidates understand that for results to be reliable they must be repeated and show a similar pattern. Many answers referred to the concept of validity and gained no credit. Part (b) discriminated well and also showed that many candidates fail to read questions carefully. For example, the correct answer to 'the chamber that pumps blood to the lungs' was the letter A, but D was often chosen. The examiners believe these candidates chose the vessel not the chamber. A similar error occurred with 'the blood vessel containing blood at the highest pressure'. Many chose the letter H instead of the letter E.Q6.This question challenged student understanding of the structure and function of the heart. About a third of students gained both marks in part (a) which was pleasing to note. Those that made errors often referred to two ventricles. Only the strongest students gained credit in part (b)(i) with most wrongly thinking that both levels would rise. Most students did better with part (b)(ii) although the majority thought the reason was linked to the heart valves.Q7.This question gave candidates a passage on delivery of antibiotics into a patient's circulation system. Almost all candidates gained 6 out of the 7 marks available. The most common error was when candidates named viruses as being killed by the antibiotic.Q8.Part (a) required candidates to complete a table about red bloodcells and white blood cells. Most scored well gaining 4 or 5 marks. In part(b) candidates needed to explain the benefits to an athlete of increased red blood cells following altitude training. Again candidates showed a good knowledge and understanding of how increased red cells would improve performance in long distance races. In part (c) candidates needed to suggest why performance is not improved in a sprint race. Many candidates scored 1 mark for noting the short duration of the race and the better candidates wrote about anaerobic respiration and less need for oxygen.Q9.Most candidates knew that platelets were involved in blood clotting and that having too few would result in excessive bleeding. Most recalled that phagocytes ingest and digest pathogens and also that lymphocytes produce antibodies. Part (c) was the most challenging component of this question with only the best candidates gaining full marks by making reference to antibodies being produced sooner and in greater quantities helping to speed the response to infection as dictated by the secondary immune response.Q10.For this question most gave a satisfactory definition of transpiration though there were some who believe that the process involves the absorption of water by plant roots. Many struggled to appreciate that the polythene bag ensures that an accurate measure of transpiration can be obtained as all the water loss has to occur from the plant. Explanations in part (c) were poor.Marks were given to students who appreciated that stomata open in light and that warm air will provide more kinetic energy to water molecules allowing them to move faster and therefore increase the rate of diffusion. Many answers gained no credit because they made reference to light increasing the rate of photosynthesis which in turn increases the need for water.Q11.Many candidates failed to attempt this question. An answer within the range of 120 to 136 was awarded both marks. Candidates gained one mark for providing an answer within the range of 60 to 68, but to get the second mark they needed to multiply by 2 to take into account the fact that the leaf has two surfaces. Any indication of a wrong number being multiplied by 2 in the working was credited with one mark.Very few candidates calculated the correct answer of 0.00138. Most candidates scored one mark for the answer 0.03. These candidates had divided 0.2 by 6 but then failed to divide by 24.The examiners were looking for some indication of surface of leafcovered, or the place where the jelly had been applied. Answers that simply stated the amount of jelly were not credited. Many candidates are aware of what a variable is, but they are not able to recognise which is the independent. Dependent and controlled variables were named in abundance.The examiners credited the word mass or weight as being indicative of the dependent variable. A variety of wrong answers were noted with the most common being 'time'.Students tended to do better on this question. Temperature was the most popular correct answer, closely followed by light or species of leaf. Surface area, leaf size and mass loss were the most frequently stated incorrect answers.(i) The correct sequence of A, C, B and D was seldom seen indicating that candidates struggled to interpret the information they were given. Examiners were allowed to award one mark if the wrong order appeared in the table providing A was written before D or C was written before B.(ii) A full explanation required candidates to make reference to stomata and the fact that they are not equally distributed on the upper and lower surfaces of the leaves. They were then expected to link this to how coverage by the jelly, effectively blocking stomata, would affect the loss in mass. Candidates struggled to gain full marks and many weak answers linked mass of jelly to mass loss.Q12.This question was on cactus plants and their adaptations to survive in dry conditions. In part a) most candidates were able to explain how the absence of leaves would reduce evaporation and the better ones linked this to lower surface area and therefore fewer stomata. In part b) while most candidates could suggest that shallow, widespread roots would increase the uptake of water the better response described the larger area for absorption and how any water could be absorbed quickly before it seeps into the sandy soil.Almost all candidates could, in part c), give the advantage of having spines as protection from being eaten. It was worrying that so many believed that this would be by predators! Some of the best candidates described how spines would maintain a still layer of moist air reducing the diffusion gradient and therefore transpiration.Q13.This question was about an experiment to measure the rate of water loss from a leafy shoot. How well students did on these items was determined by their experience of such experiments. In (a) about half of the students could identify the apparatus as a potometer. In (b) almost all could name the process by which a plant loses water. Part (c) required a description of how Stephen could set up and use the apparatus to measure the rate of water loss. Most students score 2 or 3 marks for explaining how to measure the distance in cm moved by the bubble in a certain time say a minute and repeating their readings. The students who had carried out such an experiment could describe how to set up the potometer cutting the stem under water, ensuring a water tight seal and how to introduce a bubble to the tube. In part (d) students had to explain the different rates of water loss in different conditions. Most could explain the increase in water loss in wind due to moist air being blown away thus maintaining a steep diffusion gradient. Very few could explain he reduction in water loss in lower light intensity. Many students seemed to think that less light meant less water was used in photosynthesis and did not refer to closing of stomata at all. The better students could explain why removing half the leaves reduced the rate by reducing the surface area and the number of stomata. Weak students once again described the results without any explanation of their cause.Q1.507365136310Q2.507365207418Q3.Q4.659765176925Q5.507365207418Q6.Q7.507365135065Q8.507365137580Q9.507365207418Q10.Q11.507365137580Q12.Q13.507365137580 ................
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