HORT 250 Fall 1999 Quiz 3

Select the most appropriate answer for each question from the selections provided.

 

1. Chemical weed control has been widely adopted because it:

  1. provides an effective method to control weeds
  2. requires less capital equipment than other methods
  3. has no effect on the environment
  4. is the only effective method to control weeds
  5. none of the above
  6. all of the above

 

2. Which of the following is not inhibited by at least one type of herbicide:

  1. amino acid synthesis
  2. photosynthesis
  3. cell division
  4. lipid (fat) synthesis
  5. all of these are targets for herbicide action
  6. none of these are targets for herbicide action

 

3. Broad spectrum herbicides are those that:

  1. work under a wide variety of light conditions
  2. must be applied using a "broad boom" sprayer
  3. can be applied under a wide variety of weather conditions
  4. inhibit a broad spectrum of metabolic pathways
  5. kill a wide variety of plants

 

4. Glyphosate inhibits the activity of EPSP synthase by:

  1. metabolizing one of the substrates of this enzyme
  2. binding to EPSP synthase in place of PEP
  3. degrading EPSP synthase
  4. transporting EPSP synthase to the chloroplast
  5. changing the shape of the enzyme

 

5. Transgenic plants that over-express a normal plant EPSP synthase:

  1. did not have any increased tolerance to Roundup
  2. had some increased tolerance to Roundup, but not enough for use in the field
  3. have been used directly to develop Roundup Ready crops
  4. have increased tolerance to Liberty (glufosinate) herbicide
  5. have not been produced

 

6. Bacterial genes have been used to make plants with tolerance to Roundup. These genes encode:

  1. an enzyme that prevents uptake of Roundup by plants
  2. an enzyme that restricts transport of Roundup throughout the plant
  3. an enzyme that degrades EPSP
  4. a form of EPSP synthase that is not inhibited by Roundup
  5. a form of EPSP synthase that does not bind PEP

 

7. Which two processes have been manipulated in transgenic plants to produce transgenic crops with resistance to specific herbicides:

  1. herbicide uptake and herbicide metabolism
  2. site of action of the herbicide and herbicide transport
  3. herbicide metabolism and site of action of the herbicide
  4. herbicide transport and herbicide metabolism

 

8. Plants with resistance to the imidazolinone class of herbicides have been produced by:

  1. identifying plants that could metabolize imidazolinones
  2. transferring into plants a bacterial gene for an enzyme to metabolize imidazolinones
  3. selecting cells (in tissue culture) and plants (in the field) that were resistant to imidazolinones
  4. all of the above
  5. none of the above

 

9. RoundUp Ready soybeans:

  1. cost the same to buy (as seed) as regular soybeans
  2. have not yet been planted on a significant fraction of the soybean acreage in the US
  3. are the only crop on the market with resistance to this broad spectrum herbicide
  4. have had little effect on the sale of herbicides for weed control in soybeans
  5. all of the above
  6. none of the above

 

10. Bacteria provide a valuable source of genes for modification of crop plants, for example altering herbicide tolerance, because:

  1. it can be straightforward to identify bacteria with unusual properties
  2. many genes have been sequenced and identified in different bacteria
  3. there is a lot of diversity among populations of bacteria
  4. isolating genes from bacteria is relatively easy
  5. all of the above
  6. none of the above