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Flashcards in Gibberellins Deck (20):
1

gibberellins are best knowns as regulators of stem height growth and --

seed germination

2

principal and most bioactive component of giberellic acid

GA3

3

GA cause plant elongation responses especially in dwarf varieties and in rosette plants

bolting

4

higher concentrations found in -- than vegetative seeds

immature seeds

5

GAs possess a tetracyclic skeleton with -- atoms

19-20

6

T/F: GAs are synthesized throughout the life cycle

true

7

GA is independent of the auxin effect and has a -- lag period

longer

8

GA increase wall extensibility and also -- yield threshold

reduces

9

GA biosynthesis inhibitors are used to reduce height in crops --> reduce collapse of tall grasses and reduce -- and the etiolation response

self-shading

10

GA mutants have -- roots

shorter

11

photoperiodic flower induction is mediated by GA in some species, GA can substitute for -- requirement for flowering in many plants such as rosette species

long-day

12

in maize, GA suppress -- dev

stamen

13

cucumber, hemp, and spinach GA promote -- dev

male

14

GA required for dev of pollen grain and formation of --

pollen tube

15

fruit growth following pollination

fruit set

16

GA can't restore normal dev because exogenous GA cannot enter --

new seeds

17

if seeds are imbibed, GA can sometimes overcome the ned for light or cold treatment for gemination

stratification

18

GA --> enzymes like -- by the aleurone layer of germinating cereal grains

amylase

19

embryo has a specialized absorptive organ

scutellum

20

endosperm has two tissues

starchy endosperm and outer aleurone layer