TLS Online TPP Program

#Question id: 12409


The Chemical Structure of ABA Determines Its Physiological Activity, 15 carbon compound 
a) The orientation of the carboxyl group at carbon 2 determines the cis and trans isomers of ABA. Nearly all the naturally occurring ABA is in the cis form
b) S enantiomer is the natural form; commercially available synthetic  ABA is a mixture of approximately equal amounts of the S and R forms.
c) The S enantiomer is the only one that is active in fast responses to ABA, such as stomatal closure
d) In long-term responses, such as seed maturation, only R-enantiomers are active
e) In contrast to the cis and trans isomers, the S and R forms cannot be interconverted in the plant tissue
Which of the following is the correct prediction about the active form  of ABA?

#Unit 6. System Physiology – Plant
  1. a, b and e
  2. b, c and d
  3. a, c and e
  4. a, b, c and e