#Question id: 11610
#Unit 6. System Physiology – Plant
Environmental factors such as photoperiod and temperature can alter the levels of active gibberellins by affecting gene transcription for specific steps in the biosynthetic pathway such as;
a) Promotion of germination by light has been shown to be
due to increases in GA1 levels resulting from a light-induced increase in the
transcription of the gene for GA3ox, which converts GA20 to GA1
b) level of GA20-oxidase occurs in the highest amount in
shoot tips and elongating stems, is increased under long-day conditions. The fact that GA 20-oxidase is the enzyme that
converts GA53 to GA20
c) Giving cold treatment
of Thlaspiarvense and a return to high temperatures, the ent-kaurenoic
acid is converted to GA9, the most active gibberellin for stimulating the
flowering response
d) Potato plants overexpressing the GA20ox gene showed
tuberization, whereas transformation with the antisense gene for GA20ox
inhibited tuberization
Which of the following from the given above statements is correct?
#Question id: 11611
#Unit 6. System Physiology – Plant
Given below are names of phytohormones in column I and their
associated features/effects/ functions in column II.
|
Column I ( Phytohormones) |
Column II ( Features) |
|
A)
Auxin |
i) Causes seed germinations |
|
B)
Cytokinin |
ii) Plant Stress Hormone that activates many
defense responses |
|
C)
ABA |
iii)
Polar transport |
|
D)
Gibberellin |
iv) Delayed leaf senescence |
|
E)
Jasmonic acid |
v)
Causes seed dormancy |
Which of the following combination from the above statements is correct?
#Question id: 11612
#Unit 6. System Physiology – Plant
AMO-1618, which blocks GA biosynthesis at the cyclization
step, what would be the A, B and C represents. where, the control shows no
inhibitor;
#Question id: 11613
#Unit 6. System Physiology – Plant
Gibberellin can induce auxin biosynthesis and that auxin can induce gibberellin biosynthesis. If the pea plants are decapitated, leading to a cessation in stem elongation, which one of the following prediction about this experiment is correct?
#Question id: 11614
#Unit 6. System Physiology – Plant
During the biosynthesis of GA many stages will be involved in this pathway, one of which is takes place in the plastids is GGPP is converted into the ent-kaurene via two steps of pathway involving enzymes known as
#Question id: 11615
#Unit 6. System Physiology – Plant
Biosynthesis of GA including various enzyme which are belong to______I_________ and are localized in the ______II__________.