Grade 8 Biology practice

What is on the worksheet

1. A fictional population starts at 128. During one interval: 63 births, 10 arrivals, 21 deaths and 1 departures. Find the final count. Round to 3 decimal places if needed.

2. Supplied plant-tissue data show initial mass 10.2 g and final mass 11.8 g. Find signed percentage mass change. No experiment is required. Round to 3 decimal places if needed. Answer in %.

3. A supplied food-web model transfers 19% of 555 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

4. A supplied survey counts 192 plants in 10 non-overlapping quadrats, each 1 m². Find the mean density in the sampled area. Round to 3 decimal places if needed. Answer in plants/m².

5. A supplied survey counts 102 plants in 4 non-overlapping quadrats, each 1 m². Find the mean density in the sampled area. Round to 3 decimal places if needed. Answer in plants/m².

6. In supplied data, 70 of 92 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

7. A fictional population starts at 719. During one interval: 25 births, 20 arrivals, 10 deaths and 1 departures. Find the final count. Round to 3 decimal places if needed.

8. A supplied food-web model transfers 19% of 914 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

9. Supplied plant-tissue data show initial mass 9.2 g and final mass 11.6 g. Find signed percentage mass change. No experiment is required. Round to 3 decimal places if needed. Answer in %.

10. Supplied plant-tissue data show initial mass 2.4 g and final mass 5 g. Find signed percentage mass change. No experiment is required. Round to 3 decimal places if needed. Answer in %.

11. A fictional population starts at 894. During one interval: 44 births, 23 arrivals, 40 deaths and 37 departures. Find the final count. Round to 3 decimal places if needed.

12. A supplied survey counts 193 plants in 11 non-overlapping quadrats, each 2 m². Find the mean density in the sampled area. Round to 3 decimal places if needed. Answer in plants/m².

13. In supplied data, 117 of 200 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

14. A supplied food-web model transfers 8% of 1397 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

15. Supplied plant-tissue data show initial mass 5 g and final mass 5.3 g. Find signed percentage mass change. No experiment is required. Round to 3 decimal places if needed. Answer in %.

16. A supplied food-web model transfers 23% of 1048 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.

17. A supplied survey counts 41 plants in 9 non-overlapping quadrats, each 0.25 m². Find the mean density in the sampled area. Round to 3 decimal places if needed. Answer in plants/m².

18. Supplied plant-tissue data show initial mass 2.4 g and final mass 3.8 g. Find signed percentage mass change. No experiment is required. Round to 3 decimal places if needed. Answer in %.

19. In supplied data, 15 of 144 seeds germinated under the stated test conditions. Find the sample germination percentage. Round to 3 decimal places if needed. Answer in %.

20. A supplied food-web model transfers 10% of 524 kJ to the next level. Find transferred energy. The stated efficiency is not a universal ecological constant. Round to 3 decimal places if needed. Answer in kJ.