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NAME _____________________________                                                         BIO 567

Code name ___________________________ EXAM II                                       Spring 2002

1. Write definitions that reflect each term’s significance to physiological ecology (20 pts).
- Secondary dormancy (seeds)

– Stratification

– Alternation of generations

- Synchronized flight

- Delayed fertilization

- Double fertilization

- Hemoglobin P₅₀

- Krummholz effect

- Bird lungs

- Rhizosphere

2. Suppose that just before the mature seed is released from a particular native plant species of our region you collect seeds for use in a future experiment. Assume you have a good seed supply, but find the seed is in a condition of primary dormancy. Your immediate challenge is to determine what it will take to break this dormancy. List (and explain) FOUR procedures you would utilize to try and break seed dormancy. Briefly explain for each procedure the process or manipulation you would go through. (10 points)

3. Select EITHER insects OR amphibians and explain briefly the major anatomical changes of metamorphosis, and the endocrinology that controls these changes. (10 points)

4. Describe the significance of aerenchyma tissue formation. (5 points)

5. A. Draw a graph (using a solid line) showing body temperature of a hibernating small mammal which hibernates from December to March. (3 points)

        Nov     -     Dec     -     Jan     -     Feb     -     Mar     -     Apr

B. Draw on the same graph (using a dotted line) the relative metabolic rate for the same animal over the time period shown. (2 points)

C. Describe the physiological changes are associated with the entry into the torpid state? (5 points)

D. Describe the physiological mechanisms used for arousal from the torpid state? (5 points)

6. Answer either A or B: (10 points)

A. Describe a sequence of events that will lead to flowering of an obligate, short-day plant. Be sure to include in your discussion the season of the year you think this might occur and details about the mechanism of perception of the photoperiod to include: receptor molecule; receptor plant organ; active irradiance wavelength; how time is measured; any plant hormone involvement (i.e., a signal transduction); and in general current evidence on how the system works!

B. Fill in the following table according to the heading information requested:

7. Describe the physiological role of melatonin in vertebrates. This should include where it is synthesized, when/how it is synthesized, and what effects this hormone has on the body. (5 points)

8. A. What factors are important is the selection (evolutionarily) of the best time for young to be produced? (2 points)

B. Once the best time for young is determined, what factors are important in determining (evolutionarily) when mating should occur? (2 points)

C. Once the best time for mating is determined, what factors are important in determining (evolutionarily) when the reproductive process should begin? (2 points)

D. Once the best time for "turning on" the reproductive process is determined, what is the endocrinological pathway for this (in vertebrates)? (2 points)

E. Once the best time to start the reproductive process is determined, the animals must tell when that time of the year is occurring. List four (4) major environmental cues that are used for this seasonal clock. (2 points)

9. What is the general relationship between seed size and survivorship for North American tree species grown in the shade (hint: provide a clearly labeled graph)? Provide an explanation for this relationship? (5 points)

10. Describe some basic physiological differences between juvenile and adult plants (you can use traits of "young" vs. "old" leaves in part of your answer). (5 points)

11. Complete the table about osmoregulation in marine vertebrates. (5 points)