25.E: Seedless Plants (Exercises)
25.1: Early Plant Life
Review Questions
The land plants are probably descendants of which of these groups?
- green algae
- red algae
- brown algae
- angiosperms
- Answer
-
A
Alternation of generations means that plants produce:
- only haploid multicellular organisms
- only diploid multicellular organisms
- only diploid multicellular organisms with single-celled haploid gametes
- both haploid and diploid multicellular organisms
- Answer
-
D
Which of the following traits of land plants allows them to grow in height?
- alternation of generations
- waxy cuticle
- tracheids
- sporopollenin
- Answer
-
C
Free Response
Why did land plants lose some of the accessory pigments present in brown and red algae?
- Answer
-
Sunlight is not filtered by water or other algae on land; therefore, there is no need to collect light at additional wavelengths made available by other pigment coloration.
What is the difference between extant and extinct?
- Answer
-
Paleobotanists distinguish between extinct species, which no longer live, and extant species, which are still living.
25.2: Green Algae - Precursors of Land Plants
Review Questions
What characteristic of Charales would enable them to survive a dry spell?
- sperm with flagella
- phragmoplasts
- sporopollenin
- chlorophyll a
- Answer
-
C
Which one of these characteristics is present in land plants and not in Charales?
- alternation of generations
- flagellated sperm
- phragmoplasts
- plasmodesmata
- Answer
-
A
Free Response
To an alga, what is the main advantage of producing drought-resistant structures?
- Answer
-
It allows for survival through periodic droughts and colonization of environments where the supply of water fluctuates.
25.3: Bryophytes
Review Questions
Which of the following structures is not found in bryophytes?
- a cellulose cell wall
- chloroplast
- sporangium
- root
- Answer
-
D
Stomata appear in which group of plants?
- Charales
- liverworts
- hornworts
- mosses
- Answer
-
C
The chromosome complement in a moss protonema is:
- 1 n
- 2 n
- 3 n
- varies with the size of the protonema
- Answer
-
A
Why do mosses grow well in the Arctic tundra?
- They grow better at cold temperatures.
- They do not require moisture.
- They do not have true roots and can grow on hard surfaces.
- There are no herbivores in the tundra.
- Answer
-
C
Free Response
In areas where it rains often, mosses grow on roofs. How do mosses survive on roofs without soil?
- Answer
-
Mosses absorb water and nutrients carried by the rain and do not need soil because they do not derive much nutrition from the soil.
What are the three classes of bryophytes?
- Answer
-
The bryophytes are divided into three phyla: the liverworts or Hepaticophyta, the hornworts or Anthocerotophyta, and the mosses or true Bryophyta.
25.4: Seedless Vascular Plants
Review Questions
Microphylls are characteristic of which types of plants?
- mosses
- liverworts
- club mosses
- ferns
- Answer
-
C
A plant in the understory of a forest displays a segmented stem and slender leaves arranged in a whorl. It is probably a ________.
- club moss
- whisk fern
- fern
- horsetail
- Answer
-
D
The following structures are found on the underside of fern leaves and contain sporangia:
- sori
- rhizomes
- megaphylls
- microphylls
- Answer
-
A
The dominant organism in fern is the ________.
- sperm
- spore
- gamete
- sporophyte
- Answer
-
D
What seedless plant is a renewable source of energy?
- club moss
- horsetail
- sphagnum moss
- fern
- Answer
-
C
How do mosses contribute to returning nitrogen to the soil?
- Mosses fix nitrogen from the air.
- Mosses harbor cyanobacteria that fix nitrogen.
- Mosses die and return nitrogen to the soil.
- Mosses decompose rocks and release nitrogen.
- Answer
-
D
Free Response
How did the development of a vascular system contribute to the increase in size of plants?
- Answer
-
Plants became able to transport water and nutrients and not be limited by rates of diffusion. Vascularization allowed the development of leaves, which increased efficiency of photosynthesis and provided more energy for plant growth.
Which plant is considered the most advanced seedless vascular plant and why?
- Answer
-
Ferns are considered the most advanced seedless vascular plants, because they display characteristics commonly observed in seed plants—they form large leaves and branching roots.