Review Book Answer Key

Living Environment

Review Book Answer Key

Topic 1

Review Questions

1. Human body cells and the cells of a single-celled organisms, such as an amoeba, are alike in that they both maintain homeostasis and both require energy – OR – both are made of cells that possess cytoplasm and both carry their genetic information in the form of DNA

2. 3

3. 4

4. You could use a microscope to look for cells. Living organisms are composed of cells. Nonliving things are not composed of cells.

5. 4

6. 1

7. 2

8. 2

9. 3

10. Living organisms maintain homeostasis and reproduce. Nonliving things do not maintain homeostasis and are not able to reproduce.

11. 1

12. 1

13. 3

14. 1

15. 3

16. 3

17. 3

18. 4

19. 2

20. 4

21. Receptors

22. 2

23. 4

24. 4

25. 2

26. 3

27. 4

28. 1

29. 2

30. 1

31. 2

32. 2

33. 2

34. 3

35. 1

Regents Practice

Part A

1. 2

2. 4

3. 1

4. 4

5. 3

6. 2

7. 4

8. 1

9. 4

10. 3

11. 1

12. 4

13. 4

19. 2

20. 2

Part B

22. The algae cells could not survive without mitochondria because they would be unable to carry out cellular respiration, which releases the energy stored in nutrients for the cell to use.

23. Cells must communicate so that their activities can be coordinated. This is necessary for the organism to respond as a whole and to maintain homeostasis.

24. 3

25. 3

26. 2

Part C

27. Diffusion can occur in a dead cell because it does not require outside energy. Active transport cannot occur in a dead cell because active transport requires a source of energy. A dead cell is not able to release energy from nutrients. Examples to illustrate this would be the fact that water and sugar can diffuse across dialysis tubing (remember this in our state lab?). The dialysis tubing is not alive. When a cell such as a paramecium dies, it cannot continue to pump excess water out. The paramecium fills with water and bursts. When the cell is alive, it can use energy to pump the excess water out that keeps entering by diffusion.

28.The cells of the pond organism contained a lower concentration of water and more salt than the salt solution. Therefore, the water moved from the outside environment )where it was a higher water concentration) to the inside of the cell (where there was a lower water concentration) and caused the cell to swell.

The land organism’s cells contained a higher concentration of water and a lower concentration of salt than the surrounding water. Therefore, water diffused out of the cells making them shrink.

29. Salt is a good preservative because it causes the water to diffuse out of bacterial cells, and the dehydration kills them. Salt causes this to happen because the concentration of water inside of the bacterial cells is greater than it is in the highly salty environment outside; therefore, water diffuses out. The food does not spoil because there are no living bacteria around to cause spoilage.