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ECOL 182 (Spring) Intoductory Biology - Exam Three Frequently Missed Questions

This is a list of the questions that seemed to be missed at a relatively higher rate. I've also placed some comments below each. The correct answers are in bold.

9. Life evolved the ability to transform light energy into chemical bonds that can be used to fuel cellular metabolism:

1. sometime after the evolution of photoautotrophy
2. at least 3.6 billion years ago
3. following the evolution of much of the glycolitic pathway
4. both a and b
5. both c and b

This was a straightforward definition question that came right from the notes (which I also repeated several times). The part that probably threw folks is the 'glycolitic' pathway, which would have required you recall that glycolysis is a component of respiration.

10. Photosystem I and Photosystem II refer to the two forms of the photosynthetic complex that can be found:

1. co-existing in eukaryotic photoautotrophic cells.
2. can be found operating in isolation in bacteria.
3. can be found competing for light energy in different plant species.
4. both a and b.
5. none of the above.

Again, this came right from the notes, and a point I tried to keep hammering home - that these structures have an origin that is in isolated bacteria and that they combine in more derived organisms. A large number of people just picked the first answer.

15. If sugars produced in the chloroplast are not removed to the cytosol by means of a photophate translocator, which event occurs?

1. CO 2 fixation by RUBISCO increases.
2. Phloem cells unload sugars into vessel elements to make up for reductions in transpiration.
3. Chloroplasts fill with starch and the Calvin Cycle does not operate.
4. Both b and c.
5. None of the above.

Oh no! This one was right off of my web site, but I simply changed the question to be the opposite process. Half of the folks got it and half simply didn't read it.

19. Embryophytes contain

1. Little organs that can grow into complete new haplo-diploid individuals in each life cycle stage.
2. A diverse group of organisms, including land plants and all algae.
3. All groups of terrestrial plants except the seed plants.
4. Both a and c.
5. None of the above.

This one (and the next several) required that you knew the definition of embryophytes (this was an exercise I suggested you do - define embryophytes, non-tracheophytes, traacheophytes, seed plants, gymnosperms, angiosperms).

24. Non-tracheophytes distribute water and nutrients throughout their bodies by the use of:

1. Vessel elements and tracheids.
2. Xylem and phloem.
3. Chloroplasts and stomata.
4. Leaflets and sieve tube elements.
5. None of the above.

25. In non-tracheophytes,

1. The visible green structure that dominates the life cycle is the sporophyte.
2. The visible green structure that dominates the life cycle is the gametophyte.
3. The visible green structure that dominates the life cycle is the gametangia.
4. Both b and c.
5. None of the above.

26. Bryophyta, which are fairly basal plants, have hydroid cells, which function in an analogous way to ________ cells in angiosperms.

1. Phloem
2. Xylem
3. Stomata
4. Mesophyll
5. None of the above

43. The driving force for mass flow of solution in xylem derives from _________, where as in phloem it is from _______.

1. Transpiration, sucrose concentrating
2. Tension, negative pressure
3. Active transport, tension
4. Both a and c
5. None of the above

Quite a few people picked the second answer, which is not correct for the second part of the answer - remember it must be the the most correct answer.