1. Week 4 – Objective 3 Week of Feb. 23 rd – Day 1

2. The diagram above represents a virus with its surface markers. The diagrams below show various animal cells with receptor sites. Which of the following cells is most likely affected by this virus? 1.

3. 2. Which of the following is found in both cells and viruses? A Silica B Genetic material C Digestive cavity D Flagella

4. 3. What is the most common threat to a host organism posed by an invading virus? A Production of viral fluids in the bloodstream B Fermentation of acids in the digestive system C Destruction of cells by viral reproduction D Stimulation of muscle tone in the heart

5. 4. People infected with the human Immunodeficiency virus (HIV) have an increased risk of dying from secondary infections. Which of these best explains how HIV increases the danger of secondary infections? A HIV produces antigens that damage red blood cells. B HIV adds genetic material from harmful microbes. C HIV destroys helper T cells. D HIV consumes beneficial microbes in the body.

6. Answers

7. Answer is D 1.

8. Answer is B – Genetic Material 2.

9. Answer is C – Destruction of Cells by Viral reproduction 3.

10. Answer is C – HIV Destroys helper T-cells The other answers do play a role in the body’s ability to fight secondary infections. However, they do not directly affect the immune system of the body. 4.

11. Week 4 – Objective 3 Week of Feb. 23 rd – Day 2

12. 1. Which of these characteristics might help a plant species survive in an area with limited sunlight? F Bright flowers G Large leaves H Short stems J Thick cuticles

13. 2. Some mesquite trees have deeper roots than any other plant in the desert. How are deep roots an adaptation for survival in the desert? F Deep roots can protect the tree from predators. G Roots encounter cooler conditions far below the desert surface. H Roots can extend great distances to reach water. J Deep roots interact with beneficial bacteria below the surface.

14. 3. Species of the genus Toxicodendron, which includes poison ivy and poison oak, Produce a gummy oil that causes a severe itchy rash in some animals. This substance is part of theToxicodendron species’— F defense mechanisms G nutritional processes H support system J clinging ability

15. Similar sprigs of elodea were placed in four test tubes. Each test tube contained water with a different concentration of salt ranging from 0 to 3 percent. The length of each sprig was measured after 10 days. Which of these questions can best be answered with this experimental setup? F Can the amount of salt in the water help elodea avoid disease? G What happens to salt as elodea uses water? H Will elodea increase the amount of salt in the water? J Does the amount of salt in the water affect elodea growth? 4.

16. Answers

17. Answer is G – Large Leaves 1.

18. Answer is H - Roots can extend great distances to reach water. 2.

19. Answer is F – Defense mechanisms F. G. H. J. 3.

20. Answer is J Does the amount of salt in the water affect elodea growth? 4.