Unclassified

© UCLES 2025 5090/11/O/N/25 3 A student draws six different arthropods found in woodland. 1 2 3 4 5 6 When constructing a dichotomous key, which question could be used to separate arthropods 2, 5 and 6 from arthropods 1, 3 and 4? A Does it have a segmented body? B Does it have antennae? C Does it have six legs? D Does it have wings? 3

7 Which changes occur in the air spaces of a green leaf on a sunny day? carbon dioxide concentration oxygen concentration A decreases decreases B decreases increases C increases decreases D increases increases

13 Which sets of muscles contract to cause the body to breathe in ? A diaphragm and external intercostal muscles B diaphragm and internal intercostal muscles C diaphragm muscles only D external and internal intercostal muscles

© UCLES 2025 5090/11/O/N/25 20 A doctor obtains some bacteria from an infected patient. The bacteria are grown in a Petri dish containing nutrient agar jelly. The bacteria produce a grey coating on the agar jelly. The doctor then adds three paper discs, each containing a different antibiotic. The diagram shows the Petri dish 24 hours later. antibiotic X antibiotic Y antibiotic Z bacteria What can the doctor conclude from these results? A The bacteria causing this patient’s infection are not resistant to antibiotic Y. B Antibiotic X would be more effective than antibiotic Y for treating this pa

24 An athlete’s resting body temperature is 37.0 °C. After vigorous exercise for 30 minutes, the athlete’s body temperature rises to 38.6 °C. The athlete rests for 10 minutes. After resting, the athlete’s body temperature is measured again and is 37.2 °C. Which events take place in the athlete’s body during the 10-minute rest to lower their body temperature? arterioles near the surface of the skin heat energy is lost through A contract evaporation of sweat B contract shivering C dilate evaporation of sweat D dilate shivering

© UCLES 2025 5090/11/O/N/25 [Turn over 26 The diagram shows a plant grown on its side without light. Which row explains the responses shown by the roots and the shoot? roots shoot A positive gravitropism positive phototropism B negative phototropism positive phototropism C positive gravitropism negative gravitropism D negative gravitropism positive gravitropism 14

33 Bacteria reproduce by splitting into two. This can happen every 20 minutes in ideal conditions of sufficient water, food and at a warm temperature. Small numbers of bacteria do not usually make people ill. When a student takes her lunch out of the fridge, it contains 4 bacteria. After 2 hours at room temperature, it contains 256 bacteria. From the time that the food is taken out of the fridge, how long will it take before there are 16 384 bacteria in her food? A 2 hours B 3 hours C 4 hours D 5 hours