Questions Q1. Cell transport mechanisms (a) Substances in the soil are taken up by plant root hair cells. The diagram shows the direction of movement of two substances A and B across the cell membrane of a root hair cell. (i) Name process X. (ii) Name process Y. (iii) Mineral ions are taken up by the root hair cells of plants. Name the type of vessel that transports these mineral ions through the plant. (1) (1) (1)
(b) A student investigated osmosis in a courgette. The photograph shows a courgette. The student weighed pieces of courgette and placed them in five different concentrations of sugar solution. After one hour she dried and reweighed the pieces of courgette. She calculated the percentage change in mass. The graph shows the results of this investigation. (i) Draw a line of best fit on the graph. (ii) Use your line of best fit to estimate the concentration of sugar solution that would result in no change in mass. (1) (1)
estimate =...... moles perdm 3 (iii) Explain why there was an increase in the mass of the courgette in the sugar solution at 0.2 moles per dm 3. (3) Q2. The diagrams show the limbs of six organisms. (a) Many scientists believe that these six organisms evolved from one common ancestor. Describe the evidence shown in the diagrams that supports this belief. (3)
(b) Fossils can provide evidence for evolution. Explain why the fossil record is incomplete. (c) The graph suggests that the level of oxygen in the atmosphere was important for the evolution of many living organisms.
(i) How much oxygen was needed in the atmosphere for the evolution of land animals? Put a cross ( ) in the box next to your answer. (1) A 0.009% B 0.09% C 0.9% D 9.0% (ii) Suggest how photosynthesis could have changed the gas content of the atmosphere....................... (iii) Suggest why such a high percentage of oxygen in the atmosphere was needed for
large land animals to evolve. (Total for Question = 10 marks) Q3. Exercise The graph shows the heart rate of a fit person and of an unfit person at rest, during exercise and after exercise.
(a) (i) Compare the heart rate of the fit person with the heart rate of the unfit person from 5 to 15 minutes. (ii) Cardiac output = stroke volume heart rate. The stroke volume of the fit person at 10 minutes is 0.20 dm 3 per beat. Calculate the cardiac output of the fit person at 10 minutes. Use the graph to help you. (3)... dm 3 per minute
(iii) The recovery period is the time it takes for the heart rate to return to its rate at rest after exercise. Explain why the recovery period for the fit person was different from the recovery period for the unfit person. (b) Which of the following shows the direction that blood flows towards, through and from the heart? Place a cross ( ) in the box next to your answer. (3) (1) A B vena cava ventricle atrium pulmonary vein pulmonary artery atrium ventricle aorta C aorta ventricle atrium pulmonary vein D pulmonary vein atrium ventricle aorta (c) More carbon dioxide is produced by cells during exercise. Name the part of the blood that transports most of the carbon dioxide to the lungs. (1) (Total for question = 10 marks) Q4. Gas exchange (a) Gas exchange in the air sacs of the lungs takes place in a similar way to gas exchange between body cells and capillaries.
Each of these air sacs are surrounded by blood capillaries. The diagram shows one air sac. (i) Describe how oxygen is transported from the air sac into the surrounding blood capillary......................... (ii) Complete the sentence by putting a cross ( ) in the box next to your answer. The blood transports oxygen to body cells. Oxygen is used by body cells when (1) A energy is released during respiration B energy is released from carbon dioxide C glucose is produced during respiration D energy is taken in during respiration (b) The graph shows how the heart rate of a person changes during and after aerobic exercise.
(i) The volume of blood leaving the heart during one heart beat at 25 minutes is 0.07 dm 3. The person s cardiac output can be calculated using the equation: cardiac output = stroke volume heart rate Calculate the cardiac output of this person at 25 minutes. (3) cardiac output =... (ii) Explain the trend shown by the graph between 5 and 25 minutes. (3).................................... (c) Anaerobic respiration takes place when the muscle cells are not supplied with enough oxygen. Give the word equation for anaerobic respiration. (1)......
Q5. Photosynthesis The diagram shows a plant cell. (a) Complete the sentence by putting a cross ( ) in the box next to your answer. This plant cell is a (1) A B xylem vessel phloem vessel C root hair cell D leaf palisade cell (b) Explain how water moves from cell to cell in a leaf. (c) Some small plants can grow on the bark of trees.
The distribution of two plant species, species A and species B, growing on the north and south side of a tree was investigated. The results are shown in the table. (i) Draw a bar chart to illustrate the data in this table. (ii) Which piece of equipment would be used to measure the distribution of plants on the bark of the tree? Place a cross ( ) in the box next to your answer. (1) A B a pooter a sweep net C a pitfall trap D a quadrat
(iii) Suggest reasons for the distribution of species B on the north and south sides of the tree. (Total for question = 8 marks) Q6. The diagram shows a human heart. (a) (i) Draw an arrow onto the diagram to show where oxygenated blood enters the heart. (ii) Suggest how the blood flowing through the pulmonary artery would be different from the blood flowing through the aorta. (1)
(iii) Describe the role of the valve labelled on the diagram. (b) Heart disease can significantly reduce cardiac output. (i) Complete the sentence by putting a cross ( ) in the box next to your answer. Cardiac output is the volume of blood leaving the (1) A atrium every heart beat B atrium every minute C ventricle every heart beat D ventricle every minute *(ii) A reduced cardiac output would affect the performance of an athlete. Explain the effects that a reduced cardiac output would have on the muscle cells of an athlete. (6)
(Total for Question is 12 marks) Mark Scheme Q1. Answer Acceptable answers Mark (a)(i) diffusion / osmosis (1) (a)(ii) active transport active transportation (1) (a)(iii) xylem xylem vessel / tube(s) (1) (b)(i) reasonable straight line drawn throughlines drawn to include zero value are (1) all points, must be drawn with a ruler, not correct reject two lines drawn must have at least one point on either reject point to point lines ignore side of the line extrapolation to y axis (b)(ii) reading from their graph at the point ecf from 1(b)(i) (1) that line crosses x axis / 0.3M +/- half square tolerance (b)(iii) An explanation linking the following points in a logical order: Ignore movement of sugar (3)
ref to (increase in mass due to) {osmosis / movement of water / absorption of water} (1) water into the cell (1) ref to higher concentration of water outside of the courgette (1) water across (cell) membrane / cell wall (1) correct ref to sugar concentration ORA Q2. (a) Answer A description including three of the following points: all have digits/fingers (1) all have { similar bones /radius / ulna / carpals}(1) Acceptable answers Mark accept: phalanges for fingers accept: same bone structure all have a humerus bone (1) (3) pentadactyl limb (1) (b) An explanation including two of the following points: soft tissue of organisms does not form fossils (1) some fossils are yet to be found (1) fossils may be damaged (1) conditions not correct for fossil formation (1) fossils may only be fragments / not whole organisms (1) accept: references to plant or animal tissue accept: reasons why they may not be found accept: reasons for damage e.g. earthquakes accept: named conditions e.g. ph (c) (i) D 9.0% (1)
(c) (ii) lowered the level of carbon dioxide / carbon dioxide {removed / taken in} (1) increased the level of oxygen / oxygen {produced / made}(1) accept: percentage for level If CO 2 written must be correct, do not accept CO 2 (c) (iii) Any two from: large organisms {more complex/carry out greater number of functions / more cells} for (more aerobic) respiration for (more) energy Q3.
Q4. Question Number (a) Answer Acceptable answers Mark A description linking the following points high concentration (in air sacs) to lower concentration ( in blood) (1) by diffusion (1) Question Answer Acceptable answers Mark Number (a)(ii) A (1)
Question Answer Acceptable answers Mark Number (b)(i) substitution (1) 150 0.07 evaluation (1) 10.5 unit (1) dm 3 per minute (3) Question Number (b)(ii) Answer Acceptable answers Mark An explanation linking three of the following points Accept reference to muscles / cells as site for aerobic respiration (3) {heart / pulse} rate increases to increase blood flow (1) so more {oxygen / glucose} delivered to {muscles / cells} (1) for aerobic respiration (1) increased blood flow removes carbon dioxide faster (1) Question Answer Acceptable answers Mark Number (c) glucose lactic acid (1)
M ( (a)(i) Answer Acceptable answers Mark ignore any labels on the arrow (1) allow an arrow coming out of the opening of pulmonary vein into heart (a)(ii) Any two from the following: (blood in pulmonary artery) deoxygenated (1) accept reverse argument for aorta carrying less oxygen / no oxygen (a)(iii) (blood in pulmonary artery) lower pressure (1) Any two from the following: less force / slower prevent backflow (1) (from ventricle) into description of backflow atrium (1) ignore references to left atrium and deoxygenated blood (b)(i) D ventricle every minute (1) *(b) (ii) Indicative Content A description including there will less blood flow (to the muscles) because less blood leaving the heart less oxygen (reaching muscle) less glucose (reaching muscle) reduced rate of aerobic respiration less energy released less carbon dioxide removed greater rate of anaerobic respiration glucose broken down without oxygen reduced muscle contraction build up of lactic acid (in muscle cells) causing cramp / fatigue Level 0 No rewardable content 1 1-2 a limited description of 2 effects of reduced cardiac output on muscle the answer communicates ideas using simple language and uses limited scientific terminology spelling, punctuation and grammar are used with limited accuracy 2 3-4 a simple description of 4 or more effects of reduced cardiac output on
Powered by TCPDF (www.tcpdf.org) muscle, but some steps maybe missing or out of sequence the answer communicates ideas showing some evidence of clarity and organisation and uses scientific terminology appropriately spelling, punctuation and grammar are used with some accuracy 3 5-6 a detailed description of 6 or more effects of a reduced cardiac output on muscle, with the sequence largely in order and complete the answer communicates ideas clearly and coherently uses a range of scientific terminology accurately spelling, punctuation and grammar are used with few errors