Biology 206, Exam II Questions and Study Guide. 2009W

Biology 206, Exam II Questions and Study Guide. 2009W

You will be asked to answer one of the following lettered questions (ABCD or E).

A. Explain why a mobile nutrient like potassium would show signs of deficiency in older leaves before younger leaves (hint: trace this nutrient's path through the plant).

B. Describe in the context of how and why a plant changes its morphology and development once it senses light, specifically why it no longer grows as it did before sensing light.

C. What kinds of signals trigger a plant to begin flowering? How might thisdiffer from a plant located at the equator?

D. For plants, adaptations to a land environment made them radically different from plants that relied on proximity to water for reproduction. How have angiosperms overcome those barriers to reproduction, and explain what physical properties they have and how those allow them to survive and thrive terrestrially?

E. Compare the processes of nitrogen assimilation in plants with and without nitrogen fixing bacteria.

Great study questions, really…

1. How and why do plants take advantage of soil bacteria? Explain the colonization of soil bacteria and how the plant and bacteria form a symbiotic mutualistic relationship.

2. Describe the steps of a Rhizobium infection, and how this may or may not be beneficial to the plant.

3. How do angiosperms and bryophytes differ in terms of sexual reproduction and how have these differences allowed for the dominance of angiosperm species?

4. Auxin is an important hormone with numerous functions, including causing plants to bend towards light. Outline the mechanism for this reaction at the molecular level inside the plant and describe the two principal experimental designs that have supported this hypothesis.

5. Describe auxin and its general functions.

6. Explain, in detail, the journey of a pollen grain, event by event, from creation to pollination, and what triggers these events. What evolutionary measures help in the dispersal of this pollen?

7. Explain the characteristics and the processes that plants undergo to allow them to be usefull for cleaning up toxic land areas.

8. Explain the purpose of water loss in a developing seed. What advantage does it allow the seed, how does it prevent competition and permit cues to the seed. Think about the properties of water and how they might affect the seed in certain environments. Also consider the needs of a growing seed and what it needs to continue growth to maturation. Why is dehydration a practical behavior?

9. What are some adaptations a plant needs to live successfully in a terrestrial environment? Explain one of these adaptations and why it would make the plant successful.

10. Compare the life cycles of a moss, a fern, and an angiosperm. Explain how certain features of the angiosperm life cycle allow it thrive on dry land.

11. Describe what a mobile nutrient from Nutrient Group 3 does and how it is transported in a plant.

12. What are the evolutionary advantages of a plant with a dominant sporophyte generation over a plant with a dominant gametophyte generation?

13. How does fertilization differ from pollination and how do the two sperm from the male gametophyte reach the egg in the female gametophyte of flower bearing plants?

14. What is the relationship between plants and animals; what roles do animals play throughout the plant (angiosperms, specifically) life cycle?

15. Explain how plants have evolved to make sexual reproduction more efficient.

16. Discuss how the reproductive structures of angiosperms aid in sperm/spore/seed dispersal. Include in your discussion the benefits of such reproductive structures for angiosperms as compared with the reproductive methods of ferns/mosses/liverworts.

17. Consider phototropism. Explain the mechanism that makes phototropism possible and discuss how auxin could promote or inhibit this mechanism.

18. Describe at least three adaptations or characteristics angiosperms have developed that enhance their reproductive fitness and give them an "edge" over cryptograms.

19. Discuss how plants have evolved from being able to reproduce in water to reproducing on land and why it has been advantageous.

20. Explain how mycorrhizae attach and provide nutrients to plants.

21. A plant is experiencing a moblie nutrient deficiency. Describe the route the nutrient is taking, which organ shows symptoms first, and explain why this organ shows symptoms first.