Exam 29: Plant Diversity I: How Plants Colonized Land

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 sporophytes 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

Which of the following is a true statement about plant reproduction?

Which of the following is true of seedless vascular plants?

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

What is thought to be the correct sequence of the following events during the Carboniferous period? 1. vascular plants become more prevalent 2. megaphylls with large surface areas become more prevalent 3. atmospheric CO₂ levels decline by a factor of five 4. global cooling occurs, leading to widespread glaciations

Which of the following were probably factors that permitted early plants to successfully colonize land? 1. the relative number of potential predators (herbivores) 2. the relative number of competitors 3. the relative availability of symbiotic partners 4. air's relative lack of support, compared to water's support

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

Which of the following structures are in the gametophyte generation of a moss?

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?

Which of the following should have had gene sequences most similar to the charophyte that was the common ancestor of the land plants?

What is true of charophytes?

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

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

The functional role of sporopollenin is primarily to

The next few questions are based on the following description. A biology student hiking in a forest happens upon an erect, 15-cm-tall plant that bears microphylls and a strobilus at its tallest point. When disturbed, the cone emits a dense cloud of brownish dust. A pocket magnifying glass reveals the dust to be composed of tiny spheres with a high oil content. -This student has probably found a(n)

During glacial periods in the early evolution of land plants, which of the following would have been a beneficial adaptation regarding the number of stomata per unit surface area, and what accounts for it?

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

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

Which of the following statements is true of archegonia?

On a field trip, a student in a marine biology class collects an organism that has differentiated organs, cell walls of cellulose, and chloroplasts with chlorophyll a. Based on this description, the organism could be a brown alga, a red alga, a green alga, a charophyte recently washed into the ocean from a freshwater or brackish water source, or a land plant washed into the ocean. The presence of which of the following features would definitively identify this organism as a land plant?