Bio 350M/388M Plant Molecular BiologyFall 2004December 2, 2004 Exam IVName _______________________________1. Factors that can trigger flowering in plants includea. Nitrogen deficiencyb. photoperiodc. cold (vernalization)d. both b and ce. all of the above2. The first whorl of a flower to develop is thea. carpelsb. sepalsc. petalsd. stamens3. True or False. The “determination” of a meristem is a change in the developmental program.a. True b. False4. The apetala2 homeotic mutant of Arabidopsis has which of the following flower phenotypesa. sepals-sepals-stamens-carpelsb. sepals-sepals-carpels-carpelsc. carpels-stamens-stamens-carpelsd. sepals-petals-petals-sepals5. The apetala2 gene encodes a. an enzyme in the brassinosteroid pathwayb. microRNAc. MADS box gened. unique transcription factor 6. Evolutionary changes in morphology that have enabled plants to exploit low water environments include a. cylindrical (skinny) leaves b. heavy waxy coating on leavesc. loss of leavesd. all of the above7. Which of the following is not a characteristic of the heat shock responsea. rapidb. conserved (evolutionarily)c. ubiquitousd. transiente. none of the above (all are characters)8. The function of the heat shock response in plants is to a. stimulate the phase transitionb. facilitate water uptakec. promote tolerance to droughtd. promote tolerance to lethally high temperatures9. Which of the following is/are characteristics of low molecular weight (LMW) hsps in plantsa. found in the cytoplasm, chloroplasts, and ER (endomembrane system)1b. highly heat inducedc. have ATPase activityd. a and be. all of the above10. The heat shock transcription factor HSF is known to a. bind small partially palindromic sequences b. contain a leucine zipper c. be induced in its expression level by heat d. a and b e. all of the above11. Cold acclimation (CA) in plants a. is an evolutionary process b. is an inducible process c. is a quantitative genetic traitd. b and c e. all of the above12. An important aspect of CA involves the phospholipid composition of the cell membrane, which a. decreasesb. becomes richer in unsaturated fatty acyl chainsc. changes to lower the liquidgel transition temperature d. b and c e. all of the above13. Some proteins induced by cold area. late embryogenesis abundant proteins (which also protect the embryo in dry seeds)b. antifreeze proteinsc. proteasesd. a and be. all of the above14. True or False. The response to cold (CA) develops more quickly than the response to heat.a. True b. False 15. Regulation of many cold induced genes involvesa. CBF/DREB factor b. Abscisic Acidc. DRE/C elementsd. Calciume. all of the above16. Which of the following plants is most resistant to floodinga. tomato b. maize c. cactusd. rice17. The major problem with flooding for plants in the short term is a. cellular swelling b. washing away of nutrientsc. low oxygen levelsd. high chlorine levelse. high salt levels18. Anaerobic proteins (ANPs) a. are mainly involved in glycolysisb. are induced within 24 hoursc. include heat shock proteins2d. a and be. all of the above19. Plant viruses have been found that have which of the following genomesa. single-stranded RNA (+ strand)b. single-stranded RNA (- strand) c. double-stranded RNAd. dsDNAe. all of the above20. Stress due to pathogen attack is calleda. abioticb. bioticc. biotropicd. geotropice. necrotic21. Which of the following plant responses to a pathogen happens closest to the infection sitea. local b. systemic c. programmedd. hypersensitivee. SAR22. The “local” response includesa. induction of PR proteinsb. production of ligninc. oxidative reactions d. only a and b e. all of the above23. Which of the following acts as a secondary signal in the hypersensitive response and may also kill pathogensa. phytoalexinsb. phenylpropanoidsc. salicylic acidd. hydrogen peroxidee. oxygen24. A signal (local) for SAR isa. salicylic acidb. calciumc. hydrogen peroxided. systemin25. The avr gene/protein a. is found in the plant hostb. is found in the pathogenc. interacts with a pathogen molecule d. is usually a membrane protein26. R genes/proteins usually contain aa. leucine-rich repeat (LRR)b. DNA-binding domainc. kinase domaind. toll domain327. (15 pts) Describe the revised ABC model for homeotic gene control of flower development. Why did the original model have to be changed? What are homeotic genes (i.e., how do they function)? What gene must act prior to them to get flowers?28. (10 pts) Describe Flor’s gene-for-gene model of the genetic basic of disease resistance in plants. Are the genes dominant or recessive?429. (10 pts) Discuss the role(s) of hydrogen peroxide (H2O2) in the plant defense response. Where is it produced and