TLS Online TPP Program

#Question id: 18971


The following are all true about the life cycle of mosses except

#Unit 9. Diversity of Life Forms
  1. the growing embryo gives rise to the gametophyte
  2. flagellated sperm are produced
  3. antheridia and archegonia are produced by gametophytes 
  4. the gametophyte generation is dominant
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TLS Online TPP Program

#Question id: 12641

#Unit 6. System Physiology – Plant

 Among the diverse components of plant defense arsenals are proteins that interfere with herbivore digestion, Given some defense compound of plants in column I with its given action in column II

Column I

column II

I)  α-amylase inhibitors

a) Antidigestive proteins, block the action of herbivore proteolytic enzymes. After entering the herbivore’s digestive tract, they hinder protein digestion by binding tightly and specifically to the active site of protein-hydrolyzing enzymes such as trypsin and chymotrypsin

II) Lectins

b) block the action of the starch-digesting enzyme

III) proteinase inhibitors

c) A defensive proteins that bind to carbohydrates or carbohydrate-containing proteins. After being ingested by an herbivore, bind to the epithelial cells lining the digestive tract and interfere with nutrient absorption

Correctly match the defence compound withits action on herbivore;

TLS Online TPP Program

#Question id: 12530

#Unit 6. System Physiology – Plant

Some given hormones is also called a ubiquitous hormone?
a) Ethylene
b) Gibberellin
c) Abscisic acid
d) Brassinosteroids

TLS Online TPP Program

#Question id: 12519

#Unit 6. System Physiology – Plant

Some given  statements about biosynthesis of Abscisic acid ;
a) ABA is synthesized in almost all cells that contain chloroplasts or amyloplasts
b) ABA is a 15-carbon terpenoid, or sesquiterpenoid, which is synthesized in plants by an indirect pathway via 40-carbon carotenoid intermediates
c) Cleavage of the carotenoid by the enzyme NCED (9-cis-epoxycarotenoid dioxygenase) is a rate-limiting
d) Oxidation by ABA-8′-hydroxylases lead to ABA inactivation, ABA can also be inactivated by conjugation, but this is irreversible. Both types of inactivation are also tightly regulated.
Which of the following  combination from the above statements  is correct?

TLS Online TPP Program

#Question id: 12516

#Unit 6. System Physiology – Plant

ABA Is Synthesized from a Carotenoid Intermediate is takes place in___

TLS Online TPP Program

#Question id: 12410

#Unit 6. System Physiology – Plant

Precursor of the ABA is___

TLS Online TPP Program

#Question id: 12409

#Unit 6. System Physiology – Plant

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?