Question 1

The leaflike appendages of moss gametophytes may be one to two cell layers thick. Consequently, which of the following is least likely to be found associated with such appendages?

Accepted Answer

Moss gametophytes have simple leaflike structures that are only one to two cell layers thick, which allows for direct gas exchange with the environment. Consequently, they are less likely to have stomata, which are specialized structures for controlling gas exchange in more complex plants with thicker tissues.

Question 2

Which of the following characteristics helped seedless plants better adapt to life on land?

Accepted Answer

Stomata on leaves allow seedless plants to control gas exchange and limit water loss, which is important for adapting to life on land. The other choices are not as relevant to this adaptation.

Question 3

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

Accepted Answer

During the Carboniferous period, ferns, horsetails, and lycophytes were dominant plant types and also had the potential to grow to large sizes, making them suitable sources of logs for building structures. Whisk ferns and epiphytes are not known for growing to large sizes, while bryophytes are non-vascular plants and do not produce true logs. Charophytes are freshwater algae, and gymnosperms did not become dominant until later in the Mesozoic era.

Question 4

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 5

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

Accepted Answer

The presence of flagellated sperm indicates that the plant needs water for fertilization, which is a characteristic of non-seed plants. The presence of xylem with tracheids and separate gametophyte and sporophyte generations with the sporophyte dominant further narrow down the options to ferns, which have these characteristics. Gymnosperms and flowering plants have seeds, which are missing in this newly discovered species. Charophytes are a group of green algae and lack the characteristic features of the plant in question. Mosses also have flagellated sperm but their life cycle is dominated by the gametophyte generation.

Question 6

Which of the following are land plants that use the same means of getting sperm to egg that algae use?

Accepted Answer

True mosses, hornworts, and liverworts (A) as well as ferns, whisk ferns, and horsetails (B) both use water as a medium for sperm to swim to the egg, similar to algae.

Question 7

Which of the following is true of seedless vascular plants?

Accepted Answer

Whole forests were dominated by large, seedless vascular plants during the Carboniferous period. This is a well-known fact from the fossil record. The other choices are incorrect; seedless vascular plants are not necessarily larger than extinct varieties (A), spores are not the same as seeds (C), the gametophyte is not the dominant generation (D), and Sphagnum is a moss, not a seedless vascular plant (E).

Question 8

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 determining the correct classification of the plant?

Accepted Answer

The presence of microphylls or megaphylls is the key feature that distinguishes lycophytes from pterophytes. Lycophytes have only microphylls, while pterophytes have either megaphylls or compound leaves. Therefore, determining whether the plant has microphylls or megaphylls would be the most helpful in classifying it as a lycophyte sporophyte or a pterophyte sporophyte.

Question 9

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 10

Sporophylls can be found in which of the following?

Accepted Answer

Sporophylls are specialized leaves that bear spores and are found in pterophytes, which include ferns and their relatives. Mosses, liverworts, and hornworts do not have true leaves and do not produce sporophylls. Charophytes are a type of green algae and do not have the structures characteristic of land plants, including sporophylls.

Question 11

Considering that the mature sporophytes of true mosses get their nutrition from the gametophytes on which they grow, and considering these generations as individual plants, what is true of the relationship between true moss sporophytes and gametophytes?

Accepted Answer

Sporophytes of true mosses are parasites of gametophytes as they are completely dependent on the gametophyte for their nutrition. They grow on the gametophyte, but do not provide any benefit to it.

Question 12

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

Accepted Answer

In the life cycle of bryophytes (such as mosses), the sporophyte is dependent on the gametophyte for nutrition. The sporophyte grows out of the gametophyte and remains attached to it, drawing nutrients from it through a structure called the foot.

Question 13

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

Accepted Answer

Ferns that have a hermaphroditic gametophyte belong to homosporous species, where both male and female gametes are produced from the same type of sporangium. In contrast, heterosporous species produce two different types of spores that give rise to male and female gametophytes, respectively.

Answer: D 
 In ferns with hermaphroditic gametophytes, the antheridia and archegonia are often located in close proximity, and can even be combined into a single sex organ, known as the antheridiogonium. This allows for an easier transfer of sperm to eggs, as both are located in the same individual.

Therefore, both A and D are correct, but D provides more specific information about the gametangia arrangement.

Question 14

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 the following would be the most certain means of distinguishing whether it was a true moss or a club moss?

Accepted Answer

The appearance of its spore-producing structures would be the best means of distinguishing between a true moss and a club moss. This is because true mosses have gametophytes that produce spores in capsules at the top of a stalk, while club mosses have sporophylls that produce spores in cone-like structures at the ends of their stems. The other options (color, height, presence of seeds, and conducting tissues) are not reliable indicators of whether it is a true moss or club moss.

Question 15

Beginning with the germination of a moss spore, what is the sequence of structures that develop after germination?
1)embryo
2)gametes
3)sporophyte
4)protonema
5)gametophore

Accepted Answer

The correct sequence after a moss spore germinates is: protonema (4), which develops first, followed by the gametophore (5), which produces gametes (2). Fertilization of gametes leads to the formation of an embryo (1), which eventually develops into a sporophyte (3).

Question 16

At some time during their existence, bryophytes may feature

Accepted Answer

Bryophytes do have sporangia at some point during their life cycle, which is a structure that produces and contains spores. However, they do not have true roots, leaves, or microphylls like vascular plants, and umbilical cells are not a known feature of bryophytes.

Question 17

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 18

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?

Accepted Answer

The answer of As is true of the gametophytes of...

Question 19

Which of the following is true of the life cycle of mosses?

Accepted Answer

Mosses have a life cycle with alternating haploid (n) and diploid (2n) generations. The haploid generation is called the gametophyte while the diploid generation is called the sporophyte. Gametophytes produce antheridia, which produce sperm, and archegonia, which produce eggs. Fertilization occurs within the archegonia, leading to the development of a diploid sporophyte embryo. The sporophyte remains attached to and dependent on the gametophyte for its nutrition. Eventually, the sporophyte produces spores that are dispersed by wind, not water. Mosses do not have a dominant sporophyte generation.

Question 20

Arrange the following terms from most inclusive to least inclusive.
1)embryophytes
2)green plants
3)seedless vascular plants
4)ferns
5)tracheophytes

Accepted Answer

Green plants (2) are the most inclusive, encompassing all types of plants that have chlorophyll. Embryophytes (1) are a subset of green plants, including all land plants. Tracheophytes (5) are a further subset, including plants with vascular systems. Seedless vascular plants (3) are a more specific group within tracheophytes, and ferns (4) are even more specific, representing a type of seedless vascular plant.

Quiz 29: Plant Diversity I: How Plants Colonized Land