Question 1

If humans had been present to build log structures during the Carboniferous period (they weren't), which plant type(s)would have been suitable sources of logs?

Accepted Answer

During the Carboniferous period, the dominant plant types were ferns, horsetails, and lycophytes. These plants were able to grow to large sizes and form forests, providing abundant sources of logs for construction. Whisk ferns, epiphytes, bryophytes, and charophytes were not as common or large, making them less suitable as sources of logs.

Question 2

Which of the following types of plants would not yet have been evolved in the forests that became coal deposits?

Accepted Answer

Pine trees did not evolve until the Mesozoic era, which was after the period where coal deposits were formed. The other options – horsetails, lycophytes, tree ferns, and whisk ferns – were all present during the Carboniferous period and have been found as fossils in coal deposits.

Question 3

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

Accepted Answer

The characteristics described match those of ferns, which have flagellated sperm, xylem with tracheids, a dominant sporophyte generation, and do not produce seeds.

Question 4

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

Accepted Answer

Lignified vascular tissues are typically found in the stems of higher plants, providing support and transport of water and nutrients throughout the plant. Cuticle is a waxy layer on the outer surface of leaves and stems that helps prevent water loss, but is not typically found in the interior of the stem. Gametangia are reproductive structures typically found on lower plants such as algae and fungi, and are not typically found in the stems of higher plants. A single, long cell would not be able to provide the structural support needed for a plant stem. While some dead, water-filled cells may be present in the stem, a relatively high proportion of them would not be expected.

Question 5

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

Accepted Answer

Hermaphroditic fern gametophytes indicate homospory, which means that the fern produces only one type of spore that develops into a hermaphroditic gametophyte. In contrast, heterosporous plants produce two types of spores, each developing into a male or female gametophyte.

Question 6

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?

Accepted Answer

The foot is the part of the bryophyte sporophyte that is embedded in the gametophyte tissue and is responsible for transferring nutrients and water from the gametophyte to the sporophyte.

Question 7

Assuming that they all belong to the same plant, arrange the following structures from largest to smallest (or from most inclusive to least inclusive). 1. spores
2) sporophylls
3) sporophytes
4) sporangia

Accepted Answer

The correct order from most inclusive to least inclusive is sporophytes (3), sporophylls (2), sporangia (4), and spores (1). Sporophytes are the diploid generation that produces spores, sporophylls are leaves that bear sporangia, sporangia are structures that produce spores, and spores are the actual reproductive units.

Question 8

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

Accepted Answer

Sporophylls are the small, spore-producing extensions of the stem that help compose the strobilus.

Question 9

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

Accepted Answer

Bryophytes, which include mosses, liverworts, and hornworts, have a dominant gametophyte stage and a dependent sporophyte stage. The mature sporophyte of bryophytes remains attached to the gametophyte and relies on it for nutrients. In contrast, ferns and horsetails have a dominant sporophyte stage and no dependence on the gametophyte for nutrition.

Question 10

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

Accepted Answer

Bryophytes, including mosses and liverworts, lack lignified vascular tissue, which is necessary for the structural support of tall plants. This is why they never formed forests, only mats.

Question 11

This student has probably found a(n)

Accepted Answer

The presence of microphylls and a strobilus at the tallest point, as well as the emission of dense cloud of brownish dust composed of tiny spheres with high oil content, suggests that the student has found a lycophyte sporophyte.

Question 12

This organism probably belongs to the same phylum as the

Accepted Answer

The presence of a strobilus and microphylls indicates that this organism is a member of the Lycophyta division, which includes club mosses, quillworts, and spike mosses. The dense cloud of brownish dust composed of tiny spheres with a high oil content is likely spores, which is consistent with the reproductive strategy of these plants.

Question 13

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?

Accepted Answer

The appearance of spore-producing structures is the most certain way of distinguishing between True moss and club moss. True mosses have spore-producing structures called sporangia that are typically located at the tip of the main stem or on specialized branches. Club mosses, on the other hand, have cone-like structures called strobili that contain sporangia. Therefore, examining the spore-producing structures would provide the needed information for distinguishing between True moss and Club moss.

Question 14

The following characteristics all helped seedless plants become better adapted to land except

Accepted Answer

Seedless plants do not have dominant gametophytes, but rather dominant sporophytes. The other characteristics listed (vascular tissue, waxy cuticle, stomata on leaves, and branched sporophyte) did help seedless plants become better adapted to land.

Question 15

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

Accepted Answer

Sphagnum moss is known for creating acidic conditions in the water bodies it surrounds. Therefore, the pond without the Sphagnum moss mat would have less-acidic water compared to the pond with the moss.

Question 16

A major change that occurred during the evolution of plants from their algal ancestors was the origin of a branched sporophyte. What advantage would branched sporophytes provide in this stage of the life cycle?

Accepted Answer

Branched sporophytes allow for more sporangia, which leads to increased spore production, enhancing the plant's ability to disperse and colonize new areas.

Question 17

Among bryophytes, only the sporophytes of mosses and hornworts have stomata, whereas stomata are missing from liverwort sporophytes. If the common ancestor of all bryophytes had sporophytes that bore stomata, then which of these might account for their absence from liverwort sporophytes? If, in contrast to early mosses and hornworts, early liverwort sporophytes had

Accepted Answer

The answer of Among bryophytes, only the sporophytes of mosses...

Question 18

Sporophylls can be found in which of the following?

Accepted Answer

Sporophylls are found in pterophytes, which include ferns and other related plants. Mosses, liverworts, and hornworts do not have true sporophylls. Charophytes are green algae and do not have sporophylls either.

Question 19

You are hiking in a forest and come upon a mysterious plant, which you determine is either a lycophyte sporophyte or a pterophyte sporophyte. Which of the following would be most helpful in helping you correctly classify the plant?

Accepted Answer

Whether the plant has microphylls or megaphylls is the key characteristic that distinguishes lycophytes from pterophytes. Lycophytes have microphylls (small and simple leaves), while pterophytes have megaphylls (larger and more complex leaves). The presence or absence of true leaves, whether or not it has seeds, its height, or whether it has chlorophyll a or not are not necessarily diagnostic features that distinguish between lycophytes and pterophytes.

Question 20

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

Accepted Answer

The presence of a strobilus and the release of brownish dust suggest that this plant is a type of seedless vascular plant known as a club moss. Club moss spores are coated with sporopollenin, a tough polymer that helps protect the spores from environmental stressors. Therefore, upon chemical analysis of these tiny spheres, sporopollenins should be detected in substantial amounts.

Quiz 29: Plant Diversity I: How Plants Colonized Land

If humans had been present to build log structures during the Carboniferous period (they weren't) , which plant type(s) would have been suitable sources of logs?