Chapter 27: Regulating Growth and Development: The Plant HormonesMultiple-Choice Questions1. Introduction; pp. 638–639; easy; ans: eAll plant hormones: a. are equally effective in free and bound forms. b. act in the tissues where they are produced. c. are stimulatory.d. are active in large quantities.e. communicate information. 2. Introduction; p. 639; easy; ans: c_________ have recently been ranked along with the “classic five” as a major class of plant hormone.a. Systeminsb. Florigensc. Brassinosteroidsd. Salicylic acids e. Jasmonates 3. Introduction; p. 639; easy; ans: dWhich of the following is a phenolic compound with a structure similar to aspirin?a. systeminb. florigenc. brassinosteroidsd. salicylic acids e. jasmonic acid 4. Introduction; p. 639; difficult; ans: a______ activates the biosynthesis of ________, which then activates the genes that encode protease inhibitors.a. Systemin; jasmonic acidb. Jasmonic acid; auxinc. Brassinosteroid; systemind. Salicylic acid; jasmonic acide. Systemin brassinosteroids5. Auxins; p. 639; easy; ans: bIf a coleoptile tip is covered with a blackened glass tube then illuminated from the side, the coleoptile will:a. die.b. not bend.c. bend toward the light.d. bend away from the light.e. bend at right angles to the light.6. Auxins; p. 639; easy; ans: c______ is very similar to the amino acid tryptophan. a. Gibberellinb. Cytokinin c. Indoleacetic acidd. Abscisic acide. Ethylene7. Auxins; p. 641; moderate; ans: ePolar transport is ______ in stems, _______in leaves, and ______ in roots.a. acropetal; acropetal; acropetalb. basipetal; basipetal; basipetalc. acropetal; acropetal; basipetald. basipetal; acropetal; acropetale. basipetal; basipetal; acropetal8. Auxins; p. 641; difficult; ans: cIn stems, polar auxin transport occurs mainly in the:a. vessels only.b. sieve tubes only.c. vascular parenchyma cells only.d. vessels and sieve tubes.e. vessels and parenchyma cells.9. Auxins; p. 641; difficult; ans: bA PIN protein: a. is an auxin influx carrier.b. is an auxin efflux carrier.c. catalyzes the conversion of auxin to tryptophan.d. catalyzes the conversion of auxin to indole.e. is a synthetic auxin.10.Auxins; p. 642; difficult; ans: aWhich of the following statements concerning the role of auxin in developing leaves of Arabidopsis is FALSE?a. Auxin is produced first at the leaf base and later at the tip.b. Auxin stimulates the differentiation of vascular tissue.c. Auxin induces the formation of lateral veins.d. Auxin is produced by cells that will differentiate into hydathodes.e. Auxin induces the formation of the midvein.11.Auxins; pp. 642–643; difficult; ans: cIf wounding causes the destruction of vascular tissues in an herbaceous eudicot stem:a. replacement vascular tissues will not form under any conditions.b. replacement vascular tissues will form if IAA is added to the stem just below the wound.c. replacement vascular tissues will form if the leaves and buds above the wound are intact.d. water will be transported in pith cells instead of in xylem.e. food will be transported in pith cells instead of in phloem.12.Auxins; p. 643; easy; ans: aIn apical dominance, the apical bud:a. inhibits the growth of lateral buds.b. stimulates the growth of lateral buds.c. stimulates the upward growth of the stem.d. stimulates the growth of leaves.e. inhibits the downward growth of the root.13.Auxins; p. 644; difficult; ans: cWhich of the following statements concerning strigolactone is FALSE? a. It is a terpenoid derived from carotenoids.b. It stimulates bud growth.c. It is present in root exudates.d. It promotes the formation of mycorrhizae.e. It stimulates seed germination of root-parasitic plants.14.Auxins; p. 644; moderate; ans: b Which of the following statements about fruit development is FALSE?a. A parthenocarpic fruit lacks seeds.b. A parthenocarpic fruit lacks ovules.c. Applications of auxin can stimulate carpels to develop into a fruit.d. Removal of seeds from a developing fruit results in reduced fruit growth.e. Application of auxin to a deseeded receptacle stimulates fruit growth.15.Auxins; p. 644; moderate; ans: eWhich of the following statements about 2,4-D is FALSE?a. It is a synthetic auxin.b. It is used as an herbicide.c. It is not broken down in plants as readily as IAA.d. It is absorbed more readily than IAAe. It kills grasses more readily than broad-leaf weeds..16.Cytokinins; p. 645; easy; ans: aFolke Skoog and his colleagues found that ______ stimulated cells of tobacco to divide in culture.a. coconut milkb. a sugarc. a salt d. a vitamine. auxin17.Cytokinins; p. 645; moderate; ans: cWhich of the following statements about cytokinins is FALSE?a. They stimulate cell division.b. They are present in bleeding sap.c. Kinetin is a naturally occurring cytokinin.d. They are found primarily in actively dividing tissues and in root tips.e. The most active naturally occurring cytokinin is zeatin.18.Cytokinins; p. 646; moderate; ans: bWhen tobacco pith callus is treated with higher concentrations of auxin than kinetin, ______ is(are) formed.a. more callusb. rootsc. budsd. leavese. vascular tissue19.Cytokinins; p. 646; moderate; ans: aIn roots of Arabidopsis, cytokinin ______ the initiation of lateral roots by preventing the establishment of a(n) ______ gradient.a. inhibits; auxinb. inhibits; gibberellinc. stimulates; auxind. stimulates; gibberelline. stimulates; ethylene20.Cytokinins; p. 646; difficult; ans: dIn studies of leaf senescence, when an excised leaf containing radioactive amino acids is spotted witha kinetin-containing solution, the spot:a. turns yellow and becomes nonradioactive.b. turns yellow and becomes more radioactive.c. remains green and becomes nonradioactive.d. remains green and becomes more radioactive.e. turns brown and becomes nonradioactive.21.Cytokinins; p. 646-647; easy; ans: dCytokinins are synthesized in ____ and transported from there to all other parts of the plant.a. stemsb. shoot apical meristemsc. leavesd. rootse. fruits22.Ethylene; p. 647; moderate; ans: bWhich of the following statements about ethylene is FALSE?a. The final step in its synthesis in plants is catalyzed by enzymes on the tonoplast.b. Its synthesis in plants begins with the amino acid tryptophan.c. It exerts an influence on many aspects of plant growth and development.d. It is the active component of illuminating gas that affects plant development.e. It has the formula H2C=CH2.23.Ethylene; p. 647; difficult; ans: cIn etiolated pea seedlings,