Lignin and cellulose provide rigidity to the cell walls of plants. But in most fungi, chitin performs this role. Why is it logical that most fungi don't have lignin or cellulose in their cell walls?

The Greek root ecto means 'outer.' Why are ectomycorrhizal fungi, or EMF, aptly named?a. Their hyphae form tree-like branching structures inside plant cell walls.b. They are mutualistic.c. Their hyphae form dense mats that envelop roots but do not penetrate the cell walls.d. They transfer nitrogen from outside their plant hosts to the interior.

SCIENTIFIC INQUIRY • INTERPRET THE DATA The grass Dichanthelium lanuginosum lives in hot soils and houses fungi of the genus Curvularia as endophytes. Researchers tested the impact of Curvularia on the heat tolerance of this grass. They grew plants without (E−) and with (E+) Curvularia endophytes at different temperatures and measured plant mass and the number of new shoots the plants produced. Draw a bar graph for plant mass versus temperature and interpret it.

Explain why fungi that degrade dead plant materials are important to the global carbon cycle. Do you accept the text's statement that, without these fungi, 'Terrestrial environments would be radically different than they are today, and probably much less productive'? Why or why not?

Evaluate each of the following defects. Which could lead to uncontrolled growth in cancer? Select True or False for each statement.T/FThe overexpression of MPF activity.T/FA nonfunctional Rb protein.T/FThe overexpression of G1 cyclin.T/FA nonfunctional E2F protein.

Fungi feed by .a. producing their own food with the help of sunlight;b. chasing and capturing other living organisms;c. growing on their food source and secreting chemicals to break it down;d. filtering bacteria out of their surroundings;e. producing spores

Under a microscope, a piece of a mushroom would look most likea. jelly.b. a tangle of string.c. grains of sugar or salt.d. foam.

Lawns are sometimes fertilized with nitrate that can be washed into neighboring woodlots by rain. If the trees in that woodlot are associated with EMF, what effect might the excess nitrate have on the fungi and/or trees?a. Fungal growth may be stimulated, causing the trees to transport more nitrogen to the fungi.b. The fungi may secrete more peptidases to break down the nitrate.c. The trees may take up the nitrate directly into their roots and rely less on the fungi.d. The excess nitrate may stimulate the fungi to transport more sugar to the trees.

A particular cell type spends 4 hours in G1 phase, 2 hours in S phase, 2 hours in G2 phase, and 30 minutes in M phase. If a pulse–chase experiment were performed with radioactive thymidine on an asynchronous culture of such cells, what percentage of mitotic cells would be radiolabeled 9 hours after the pulse?a. 0 percentb. 50 percentc. 75 percentd. 100 percent