Exam 29: Plant Diversity I: How Plants Colonized Land

The following questions are based on the description and Figure 29.1 below, which is the same as Fig. 29.10 in the textbook. Researchers tested nitrogen loss from soil where the moss Polytrichum was growing, to soil from which Polytrichum had been removed. The data are presented below. Figure 29.1 -A potential source of nitrogen in a sandy soil environment might be the bacterium, Rhizobium, which inhabits the root nodules of leguminous plants. Which of these statements is True, and should prevent Rhizobium or other root-inhabiting nitrogen-fixers from contributing nitrogen to the soil in this experiment?

Which event during the evolution of land plants probably made the synthesis of secondary compounds most beneficial?

If intelligent extraterrestrials visited Earth 475 million years ago, and then again 300 million years ago (at the close of the Carboniferous period), what trends would they have noticed in Earth's terrestrial vegetation over this period? 1) a trend from dominant gametophytes to dominant sprophytes 2) a trend from sporangia borne on modified leaves (sporophylls)to sporangia borne on stalks (seta) 3) a trend from no True leaves, to microphylls, to megaphylls 4) a trend from soil-surface-hugging plants to "overtopping" plants 5) a trend toward increased lignification of conducting systems

Closer observation reveals that these small spheres are produced on tiny extensions of the stem, each of which helps compose the strobilus. These small, spore-producing extensions of the stem are called

Refer to the information below to answer the following questions. Researchers decided to test the hypothesis that if the 2-m tall Polytrichum gametophyte-sporophyte plants had acted as a physical buffer, then they would have reduced water's ability to erode the soil, and carry away its nitrogen. They began with four equal-sized areas where Polytrichum mosses grew to a height of 2 m above the soil surface. One of the four areas was not modified. In the second area, the mosses were trimmed to a height of 1 m above the soil surface. In the third area, the mosses were trimmed to a height of 0.5 m above the soil surface. In the fourth area, the mosses were trimmed all the way to the ground, leaving only the rhizoids. Water, simulating rainfall, was then added in a controlled fashion to all plots over the course of one year. Figure 29.2 below presents four graphs, which depict potential results of this experiment. (A) (C) (B) (D) Figure 29.2 -Which of these potential results of applying a metabolic poison to the rhizoids of Polytrichum should interfere the least with the ability to draw valid conclusions from this experiment?

Choose the adaptation below that best meets each particular challenge for life on land. -protection from desiccation

Which of the following characteristics, if observed in an unidentified green organism, would make it unlikely to be a charophyte?

Identify each of the following structures as haploid or diploid: A)sporophyte B)spore C)gametophyte D)zygote E)sperm

A researcher wants to develop a test that will distinguish charophytes and land plants from green algae. Which of the following chemicals would be the best subject for such an assay?

Besides oil, what other chemical should be detected in substantial amounts upon chemical analysis of these small spheres?

In which of the following taxa does the mature sporophyte depend completely on the gametophyte for nutrition?

In plants, which of the following are produced by meiosis?

A dissection of the interior of this organism's stem should reveal

If you are looking for structures that transfer water and nutrients from a bryophyte gametophyte to a bryophyte sporophyte, then on which part of the sporophyte should you focus your attention?

The most recent common ancestor of all land plants was probably similar to modern-day members of which group?

A botanist discovers a new species of plant in a tropical rain forest. After observing its anatomy and life cycle, the following characteristics are noted: flagellated sperm, xylem with tracheids, separate gametophyte and sporophyte generations with the sporophyte dominant, and no seeds. This plant is probably most closely related to

Some green algae exhibit alternation of generations. All land plants exhibit alternation of generations. No charophytes exhibit alternation of generations. Keeping in mind the recent evidence from molecular systematics, the correct interpretation of these observations is that

Bryophytes never formed forests (mats, yes, but not forests)because

You are hiking in a forest and happen upon a plant featuring a central stemlike structure from which sprout many, tiny, leaflike structures. Which of these would be the most certain means of distinguishing whether it was a True moss, or a club moss?

Of the following list, flagellated (swimming)sperm are generally present in which groups? 1) Lycophyta 2) Bryophyta 3) Angiosperms 4) Chlorophyta 5) Pterophyta