1. Diagram 1 shows a baby in its mother’s uterus. placenta umbilical cord amniotic fluid around the baby muscles in wall of uterus diagram 1 (a) What is the normal length of pregnancy in humans? .................. months 1 mark (b) (i) What is the function of the amniotic fluid around the baby? ................................................................................................................ 1 mark (ii) As a baby is born, it is pushed out of the mother’s body. Look at the diagram above. What happens in the wall of the uterus to push the baby out? ................................................................................................................ ................................................................................................................ 1 mark Stoke-On-Trent LA Schools 1 (c) How does a baby get oxygen from its mother while it is inside its mother’s uterus? ......................................................................................................................... ......................................................................................................................... 1 mark (d) Diagram 2 shows a section through the mother’s lungs. trachea (windpipe) bronchus bronchiole alveolus diagram 2 Look at diagram 2. From which labelled part is oxygen absorbed into the blood? .............................................. 1 mark maximum 5 marks Stoke-On-Trent LA Schools 2 2. (a) Air is a mixture of gases. The pie chart represents the percentages of different gases in air. On the line by each section of the pie chart, write the name of the correct gas. Two have been done for you. 0.04% carbon dioxide 1.96% water vapour and other gases 20% 78% not to scale 2 marks (b) On a cold day, droplets of water form on a cold window. Explain how these droplets form. ......................................................................................................................... ......................................................................................................................... ......................................................................................................................... 2 marks Stoke-On-Trent LA Schools 3 (c) The word equation below represents a process taking place in the cells of the human body. glucose + oxygen carbon dioxide + water (i) What process does this word equation represent? ............................................................. 1 mark (ii) As a result of this process, the proportions of oxygen and carbon dioxide in air breathed in and air breathed out change. Which one of the statements below is true? Tick the correct box. Air breathed out has less carbon dioxide and more oxygen than air breathed in. Air breathed out has less carbon dioxide and less oxygen than air breathed in. Air breathed out has more carbon dioxide and less oxygen than air breathed in. Air breathed out has more carbon dioxide and more oxygen than air breathed in. 1 mark maximum 6 marks Stoke-On-Trent LA Schools 4 3. An ecosphere is a model habitat that can last for many years. The ecosphere below is a sealed glass ball containing sea water, green algae, bacteria, a snail and shrimps. not to scale (a) The ecosphere must receive plenty of light. Explain why light is necessary for the survival of the green algae and the animals in the ecosphere. ......................................................................................................................... ......................................................................................................................... ......................................................................................................................... ......................................................................................................................... ......................................................................................................................... 3 marks (b) When organisms in the ecosphere die, they are broken down by bacteria. Nutrients, such as nitrates, are released back into the ecosphere. Why is this necessary for the survival of the other organisms in the ecosphere? ......................................................................................................................... ......................................................................................................................... 1 mark Stoke-On-Trent LA Schools 5 (c) The table shows how the mass of oxygen dissolved in water changes with temperature. temperature of the water (°C) mass of oxygen dissolved (mg/100 cm3) 15 10.2 17 9.7 19 9.3 21 9.0 23 8.7 25 8.4 27 8.1 29 7.9 This ecosphere was kept at a temperature between 17°C and 23°C. In this ecosphere, respiration in the organisms is affected less if the temperature falls to 15°C than if it rises to 27°C. Use information in the table to explain this. ......................................................................................................................... ......................................................................................................................... 1 mark maximum 5 marks 4. The table shows how hydrogencarbonate indicator solution changes colour when the concentration of carbon dioxide in it changes. concentration of carbon dioxide colour change increases orange to yellow decreases orange to purple Stoke-On-Trent LA Schools 6 Sunil set up the experiment shown below and put both test-tubes on a window-sill. Use information in the table to help you answer the questions below. (a) The indicator in test-tube A changed from orange to yellow. (i) What process, in the cells of the maggots, caused this colour change? ............................................................................................................. 1 mark (ii) Explain what happens in this process to cause the colour change. ............................................................................................................. 1 mark (b) The indicator in test-tube B changed from orange to purple. (i) What process, in the cells of the leaves, caused this colour change? ............................................................................................................. 1 mark (ii) Explain what happens in this process to cause the colour change. ............................................................................................................. ............................................................................................................. 1 mark Stoke-On-Trent LA Schools 7 (c) Sunil then put two fresh leaves into test-tube C containing 30 cm3 of orange hydrogencarbonate indicator. He added some maggots on a piece of wire mesh as shown below. He put the test-tube on a window-sill. The indicator remained orange. Explain why. ...................................................................................................................... ...................................................................................................................... ...................................................................................................................... 1 mark maximum 5 marks Stoke-On-Trent LA Schools 8 5. The diagram sbelow shows part of the respiratory system. voice box P Q R S (a) From the diagram, give the letters which label: (i) the trachea; ………………… 1 mark (ii) alveoli. ………………… 1 mark (b) (i) Which gas passes into the blood from the alveoli? ……………………………….… 1 mark (ii) Which gas passes out of the blood into the alveoli? ……………………………….… 1 mark Stoke-On-Trent LA Schools 9 (c) The walls of the capillaries and the alveoli are very thin. Why do they need to be thin? ………………………………………………………………………………………. ………………………………………………………………………………………. 1 mark (d) There are millions of alveoli in the lungs. They provide a very large surface area. Why is a large surface area necessary? ………………………………………………………………………………………. ………………………………………………………………………………………. 1 mark Maximum 6 marks 6. (a) Jasmine was trying to find out how much air she breathed out in one breath. She poured water into a bell-jar and placed it upside down in a trough of water. The bell-jar had a scale marked in cm3. before Jasmine breathed into the bell-jar Stoke-On-Trent LA Schools 10 after Jasmine breathed into the bell-jar (i) How much air did Jasmine breathe out? ……………………… cm3 1 mark (ii) Air contains carbon dioxide, nitrogen, noble gases, oxygen and water vapour. Give three differences between the composition of the air Jasmine breathed in and the air she breathed out. Compared to the air she breathed in, the air she breathed out contained: 1. ......................................................................................................... 2. ......................................................................................................... 3. ......................................................................................................... 3 marks Stoke-On-Trent LA Schools 11 (b) In the diagram below, tube A connects the lungs to the mouth. Part B is a part of the lung where gas exchange takes place. (i) On the diagram, write the names of tube A and part B. 2 marks (ii) In the wall of tube A there are 'rings' of a stiff material called cartilage. Suggest one function of the 'rings' of cartilage. ............................................................................................................ ............................................................................................................ 1 mark Maximum 7 marks Stoke-On-Trent LA Schools 12