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Biology

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Questions 1 – 13 are taken from the course website, Vascular Plants: Gymnosperms
Questions 14 – 20 are taken from Chapter 18 in the textbook.
A B C D
1. The extinct “cycadeoids” differ from the modern extant cycads by having ______________.
A. primary tissues but no secondary tissues
B. unisexual pollen and seed cones
C. different morphology of the guard cells in the epidermis
D. flowers instead of cones

A B C D
2. Cycads are dioecious, meaning that ______________.
A. there are no reproductive structures known
B. the plants drop their leaves each fall
C. they have male and female cones on the same plant
D. there are separate male and female plants

A B C D
3. Unlike the seed cone of pines, the seed cone of cycads such as Cycas revoluta is ______________.
A. a simple structure, a branch of modified leaves (megasporophylls)
B. a complex structure, a branch of modified branches (microsporophylls)
C. a complex organism, a modified gametophyte
D. none of the above are correct

A B C D
4. In cycads, as in all other gymnosperms, a pollen tube is ______________.
A. one of the most important evolutionary advances in seed plants
B. lacking, the sperm swim freely to the egg
C. extremely long, usually more than 15 cm in length
D. a means of transferring the pollen grain to the stigma

A B C D
5. Cycad fossils are ______________.
A. unknown
B. known from the late Permian
C. abundant in the Devonian, but scarce in later Periods
D. never found with cones or seeds

A B C D
6. Seed ferns ______________.
A. were the first group of plants to have true seeds
B. evolved in the Devonian and became extinct by the Cretaceous
C. were polyphyletic, and likely gave rise to several modern lines of seed plants
D. all the above are correct

A B C D
7. The Carboniferous was sometimes referred to (mistakenly) as the “Age of Ferns” because_________________.
A. fossils of seed ferns were often mistaken for true ferns
B. ferns did not evolve until the Oligocene
C. Lycophyte fossils were most abundant, and have fern-like (pinnate) leaves
D. all of the above are correct

A B C D
8. The extant gymnosperm phylum known as the Ginkgophyta is monotypic, meaning it has but one ____________.
A. seed
B. sex
C. species
D. fossil

A B C D
9. Ginkgo biloba is regarded as a “living fossil” because it ______________.
A. has microphyllous leaves without any vascular tissue
B. has silicon dioxide (glass) deposits in its leaves, giving the plant a rock-like feel
C. is nearly indistinguishable from Permian fossil ginkgoes
D. all of the above are correct

A B C D
10. One interesting and important characteristic of Ginkgo biloba is that ______________.
A. it has bisexual cones
B. its seed coat produces butanoic and hexanoic acids, which stink
C. it lacks true leaves
D. it is sterile and produces no pollen or seeds

A B C D
11. â€œGnetophytes” like Ephedra ______________.
A. may be the closest living relatives of flowering plants
B. are unknown from the fossil record
C. are the only seed plants that lack vascular tissues
D. have seeds with multiple embryos, so that a single seed produces several plants