Exam 29: Plant Diversity I: How Plants Colonized Land

If a fern gametophyte is a hermaphrodite (that is, has both male and female gametangia on the same plant), then it

Use the information that follows to answer the questions below. Big Bend National Park in Texas is mostly Chihuahuan desert, where rainfall averages about 10 inches per year. Yet, it is not uncommon when hiking in this bone-dry desert to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." At first glance, it could be a fern, a true moss, or a spike moss. -Upon closer inspection of the leaves of flower of stone, one can observe tiny, cone-like structures. Each cone-like structure emits spores of two different sizes. Consequently, which of the following is the closest living relative of flower of stone?

The following questions refer to the description below. There are many advantages for plants to living in an aqueous environment. For example, water provides support, the temperature of water fluctuates much less than on land, and external fertilization is facilitated in water. Nevertheless, plants successfully invaded land and diversified. -What evidence in the fossil record would you look for that would indicate that plants had successfully colonized land?

Structurally, phragmoplasts should be most similar to

Two small, poorly drained lakes lie close to each other in a northern forest. The basins of both lakes are composed of the same geologic substratum. One lake is surrounded by a dense Sphagnum mat; the other is not. Compared to the pond with Sphagnum, the pond lacking the moss mat should have

Use the information that follows to answer the questions below. Big Bend National Park in Texas is mostly Chihuahuan desert, where rainfall averages about 10 inches per year. Yet, it is not uncommon when hiking in this bone-dry desert to encounter mosses and ferns. One such plant is called "flower of stone." It is not a flowering plant, nor does it produce seeds. Under arid conditions, its leaflike structures curl up. However, when it rains, it unfurls its leaves, which form a bright green rosette on the desert floor. Consequently, it is sometimes called the "resurrection plant." At first glance, it could be a fern, a true moss, or a spike moss. -Which of the following features is most important in order for true mosses and ferns to survive and reproduce in the desert?

A botanist discovers a new species of plant in a tropical rain forest. After observing its anatomy and life cycle, he notes the following characteristics: 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

Refer to the following information to answer the next few 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. The figure below presents four graphs that depict potential results of this experiment. -The 2-m height attainable by Polytrichum moss is at the upper end of the size range reached by mosses. What accounts for the relative height of Polytrichum?

The following are all adaptations to life on land except

Refer to the following information to answer the next few 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. The figure below presents four graphs that depict potential results of this experiment. -Which graph of soil nitrogen loss over time in the figure most strongly supports 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?

The following traits provide supporting evidence that charophyceans are the closest relatives of land plants, with the exception of the fact that

Increasing the number of stomata per unit surface area of a leaf when atmospheric CO₂ levels decline is most analogous to a human

What is a key difference between spores and seeds?

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

If researchers found that charophyte algae lack certain traits that land plants have, can we conclude that charophytes are not the closest relatives of land plants?

The structural integrity of bacteria is to peptidoglycan as the structural integrity of plant spores is to

As is true of the gametophytes of all land plants, the gametophytes of true mosses lack stomata. Yet, the feather moss Pleurozium harbors nitrogen-fixing cyanobacteria. Which of the following is a feature of moss gametophytes that is most important for the continued survival of these cyanobacteria in the tissues of the feather moss gametophyte?

Researchers tested nitrogen loss from soil where the moss Polytrichum was growing, and compared it to soil from which Polytrichum had been removed. The data are presented below. -Loss of soil nitrogen via "gaseous emission" was found to be negligible. Rather, most loss of soil nitrogen was due to water erosion of the soil. Which of these hypotheses is least likely to account for the observed results?

Which of the following was not a challenge for survival of the first land plants?

Which of the following characteristics of plants is absent in their closest relatives, the charophyte algae?