2. Question 1 Oxygen gas can be collected from pondweed. This is done by putting pondweed in some water in a beaker and placing a funnel over it. A test-tube of water is then placed over the funnel. As the oxygen collects in the test-tube, it pushes the water out. Discuss where the labels should go (only words in bold are used). Click here to see the answer.here

3. Question 2a Jill wrote this about an animal she found in a pond. “It does not have any legs and its segmented body has no shell” This time the important parts are in bold type. When you think you have identified the animal, click here to check.here

4. Question 2b Write down two things that the key tells you about the mayfly nymph found in the pond. Find the mayfly nymph in the key. Work up the branches to find out two things about the mayfly nymph. When you think you have found them, click here to check.here

5. Question 3 What two conclusions can be drawn from these results? Look for differences between the start and two days later. Has anything disappeared from any of the dishes? If so, it’s probably been eaten by one of the animals. If there is no difference, then nothing has been eaten! CLICKCLICK

6. Question 4a American fireflies produce flashing light at night. The average number of flashes there are in a minute depends on the air temperature. At 19 o C the firefly produces 8 flashes per minute. This increases to 11 flashes per minute when the temperature is 23 o C. With a temperature of 26 o C the firefly flashes 12 times a minute and on very hot nights with an air temperature of 27 o C, 15 flashes a minute are seen. Air temperature ( o C)Number of flashes per minute 19 o C8 23 o C11 26 o C12 27 o C15 Click the mouse to see the completed table.

7. Question 4b LOOK at your graph. Have you completed the axes correctly? Make sure that the numbers on each axis increase by the same amount each time. Have you plotted the four points accurately? Does your line show the best trend possible for these results? Now compare your graph with the model answermodel answer

8. oxygen gas funnel test-tube pondweed water beaker Question 1 solution Back to question 1

9. Question 2a solution Back

10. Question 2b solution The mayfly nymph has LEGS but NO WINGS. BACK

11. Question 3 solution No Great Silver Beetles left! Great Diving Beetles eat Great Silver Beetles! No pond-weed left! Great Silver Beetles eat pond-weed. No difference after 2 days. Great Diving Beetles do not eat pond-weed.

12. Air temperature ( o C) Number of flashes per minute 0 2 4 6 1920 8 -8 - 16 - 14 - 10 - 12 - ⃓ 21 ⃓ 22 ⃓ 23 ⃓ 24 ⃓ 25 ⃓ 26 ⃓ 27 x x x x The best kind of line to draw is a line of best fit. This goes as close to as many points as possible. Question 4b solution