Exam 26: The Colonization of Land by Plants and Fungi

Please use the following information to answer the question(s) below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. -The harpy eagle, Harpia harpyja, is the largest, most powerful raptor in the Americas. It nests only in trees taller than 25 meters. It is a "sloth specialist," but will also kill agouti. Thus, if these eagles capture too many agoutis from a particular locale, they might contribute to their own demise by

When pathogenic fungi are found growing on the roots of grape vines, grape farmers sometimes respond by covering the ground around their vines with plastic sheeting and pumping a gaseous fungicide into the soil. The most important concern of grape farmers who engage in this practice should be that the

Which process occurs in fungi and has the opposite effect on a cell's chromosome number than does meiosis?

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

Please use the following information to answer the question(s) below. The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from microsporophylls (leaflike structures that contain microsporangia). Upon visiting megasporophylls (leaflike structures where megaspores are formed), the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans. -If the beetles survive by consuming cycad pollen, then whether the beetles should be considered mutualists with, or parasites of, the cycads depends upon

What adaptations should one expect of the seed coats of angiosperm species whose seeds are dispersed by frugivorous (fruit-eating) animals, as opposed to angiosperm species whose seeds are dispersed by other means? 1) The exterior of the seed coat should have barbs or hooks. 2) The seed coat should contain secondary compounds that irritate the lining of the animal's mouth. 3) The seed coat should be able to withstand low pH environments. 4) The seed coat, upon its complete digestion, should provide vitamins or nutrients to animals. 5) The seed coat should be resistant to the animals' digestive enzymes.

Please use the following information to answer the question(s) below. The Brazil nut tree, Bertholletia excels (n = 17), is native to tropical rain forests of South America. It is a hardwood tree that can grow to over 50 meters tall, is a source of high-quality lumber, and is a favorite nesting site for harpy eagles. As the rainy season ends, tough-walled fruits, each containing 8-25 seeds (Brazil nuts), fall to the forest floor. Brazil nuts are composed primarily of endosperm. About $50 million worth of nuts are harvested each year. Scientists have discovered that the pale yellow flowers of Brazil nut trees cannot fertilize themselves and admit only female orchid bees as pollinators. The agouti (Dasyprocta spp.), a cat-sized rodent, is the only animal with teeth strong enough to crack the hard wall of Brazil nut fruits. It typically eats some of the seeds, buries others, and leaves still others inside the fruit, which moisture can then enter. The uneaten seeds may subsequently germinate. -The same bees that pollinate the flowers of the Brazil nut trees pollinate orchids, which are epiphytes (plants that grow on other plants); however, orchids cannot grow on Brazil nut trees. These observations explain

Please use the following information to answer the question(s) below. Ecologists often build models to depict the relationships between organisms. In such models, an arrow is used to link two organisms in a relationship. The arrowhead is next to the organism that is affected. If the effect is positive, the arrow is labeled with (+), and if negative, the label is (-). -Which of the following characteristics of plants is absent in their closest relatives, the charophyte algae?

Which of the following sex and generation combinations most directly produces the integument of a pine seed?

Sporophylls can be found in which of the following?

What do fungi and arthropods have in common?

The generative cell of male angiosperm gametophytes is haploid. This cell divides to produce two haploid sperm cells. What type of cell division does the generative cell undergo to produce these sperm cells?

Please use the following information to answer the question(s) below. For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. Infected animals can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. Zoospores are spores of fungi (as well as some algae and protozoans) that use a flagella for swimming locomotion. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection. -A researcher took water in which a Jl population had been thriving, filtered the water to remove all bacterial cells, and then applied the water to the skins of adult amphibians to see if there would subsequently be a reduced infection rate by Bd when frog skins were inoculated with Bd. For which of the following hypotheses is this procedure a potential test?

If the kingdom Plantae is someday expanded to include the charophytes, then the shared derived characteristics of the kingdom will include 1) rings of cellulose-synthesizing complexes. 2) chlorophylls a and b. 3) alternation of generations. 4) cell walls of cellulose. 5) ability to synthesize sporopollenin.

Which of the following sex and generation combinations most directly produces the fruit?

What is true of stamens, sepals, petals, and carpels?

Please use the following information to answer the question(s) below. Fairy rings are circles of fungi that often appear in open meadows and in forest areas. In the soil beneath the fungi is an ever-extending mycelium. As the mycelium spreads to seek out more food, it sometimes will produce the fungi we see above ground. The figure depicts the outline of a fairy ring that has appeared overnight in an open meadow, as viewed from above. The ring represents the farthest advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the soil surface. -All four locations are 0.5 m below the surface. On a breezy day with prevailing winds blowing from left to right, where should one expect to find the highest concentration of free basidiospores in an air sample?

Please use the following information to answer the question(s) below. Fairy rings are circles of fungi that often appear in open meadows and in forest areas. In the soil beneath the fungi is an ever-extending mycelium. As the mycelium spreads to seek out more food, it sometimes will produce the fungi we see above ground. The figure depicts the outline of a fairy ring that has appeared overnight in an open meadow, as viewed from above. The ring represents the farthest advance of this mycelium through the soil. Locations A-D are all 0.5 meters below the soil surface. -What is the most probable location of the oldest portion of this mycelium?

Generally, wind pollination is most likely to be found in seed plants that grow

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?