Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

35 Cards in this Set

  • Front
  • Back
1. Biosynthesis occurs in ___
2. Largest amount is at the ____
3. Synthesized from_____
1. leaf primodia, developing leave & seeds
2. shoot apex (stem tips)
3. amino acid tryptophan
4. ____ auxin synthesis
5. _____ reporter gene is an auxin sensitive promoter
4. Hydathodes
5. gus reporter gene
6. gus stain blue moves where?
towards sink and stimulates differentiation od xylem tissue
Name both biologically active and inactive form of Auxin and state where it is stored and what is it associated with.
Conjugated IAA = inactive
- stored in this form
conjugated with glucose, inositol, amides, glycoprotein

IAA - biologically active form
Why is IAA degraded and what is used to degrade it?
control devel.
oxidative degredation
Name two subcellular pools of IAA
cytosol and chloroplast
IAA does not cross_____ and IAA conjugates are located in the ____
Auxin is transported ____ from _____
polarly from shoots to roots
requires energy and is gravity dependent
Auxins move____ to the tissue below. Chemiosmotic model explains polar auxin transport ____ form of IAA move through________ concentrated on ________.
anionic form of IAA move through auxin transport carriers concentrated on basal end. Active and passive movement
___ protein are carriers specifically transports IAA at basal ends of cells.
Where are these carriers cycled?
cycled to membrane
How does IAA move through sieve tube cells of phloem? Polar or nonpolar?
How do levels of IAA differ in regions of plants? What are the optimum concentrations in stem and root tissue?
What causes inhibition
Optimum conc 10-5, 10-6 M stem tissue
Optimum conc 10-10, 10-12 for root tissue
higher conc than these causes stem inhibiiton
name some physiological effxs of auxins:
(cells, stems, roots, cell wall, ect)
cell elongation
promots growth in stems
inhibits growth in roots
rapidly increases extensibility of cell wall - 5 to 10 fold in 10 min. Wall loosening protien (expansisn) brks cellulose links under acidic condts.
Acid growth hypothesis
auxin rapidly increases extensibility of cell wall and increases cell extension
Which protein inhibitor inhibits cell wall loosening
What does auxin do with ATPases?
activates H ion atpases
synthesizes H ion atpases
If the root cap was removed from the root apex and the root was
placed on a horizontal position, what results would you expect and why?
Root tissue is more sensitive to IAA than stem tissue. IAA concentration on the bottom is so much it causes the root to bend down. If you cut off the root cap where IAA is located you don’t have the settling out of IAA so you don’t have root bending down. So if you were to lay the root apex on its side you would not have root bending down because no IAA present. Elongation of the root would cease.
If the stem apex was cut from stem tip and replaced by a block of
agar, what results would you expect and why?
IAA forms abscission zone and petioles die.
If a leaf blade was removed from the end of its petiole and a paste
containing IAA was placed on the cut petiole, what results would you
expect and why?
Transport of Auxin is basipetal in stems and leaves. Auxin always moves towards the base of stems and leaves so if you remove the blade and place auxin there, the petiole would grow.
Cessation of wall expansions is____?
Secreted matrix polysaccharides are altered to _____
De-esterfication of pectins leads to _____
Cross linking of phenolic groups in the wall makes
1. irreversible
2. form tighter complexes
3. more rigid pectin gels
4. for a more rigid cell wall
auxin stimulates cell elongation in 1.
2. ____more sensitive to auxin
3._____may play a role in the lateral redistribution of auxin
1. stems
2. roots
3. Root cap
Name the hormone which regulates apical dominance.
Name two hormones which also play a role in apical dominance.
1. auxin
2. cytokinin and ABA
Name all of the things that auxin regulates
1. apical dominance, 2. formation of both lateral and adventitious roots 3. fruit development: fruit set/ parthenocarpy
What does auxin induce
vascular differentiation
What do High and low auxin concentrations stimulate
1. high auxin conc = xylem and phloem tissue develope
2. low auxin conc = stimulate phloem differentiation
What does auxin have to do with gravitropism? describe negative and positive types:
gravitropism - roots grow down, shoots grow up.
(+) gravitropism = in root, no pin cells present in root to extend cells so gravity is only way to make extension.
(-) gravitropism = in shoot, cells on bottom extend longer than on top due to gravitropism.
Why don't IAA elongate cells in stem?
2.Give an exp of IAA in root tissue
3.Is IAA settling out?
cuz cells may not have genes there to develop pins & elongate

2.Root tissue more sensitive than stem tissue. IAA conc on bottom is so much it causes root to bend down. Plants are sensitive to hormone concentration so they try to have as little as possible.

3. No bc molecules are constantly moving, statoliths keep IAA in 1 place.
ability of an organism  to detect day length
1.Shedding leaves, flowers, & fruits-
These abscised parts are (2)? .
After leaf abscission; differentiation of distinct layer of cells is called (3).
2. abscission zone
3. abscission layer
Describe GA?
A plant growth substance (phytohormone) involved in protion of stem elongation, mobilization of food reserves in seeds & ect processes. Its absence results in dwarfism of some plants. Family of diterpene acids made by terpenoid pathway in plastids and modified in ER & cytosol before reaching activated form. Orig derived from gibberella fungus
GA synthesis controlled by?
How is GA sythesized ?
Synthesis controlled by genes since dwarf plants are affected and
normal size plants are not affected by GA
Gibberellins are synthesized via the Terpenoid Pathway
Where is GA made?
largest conc made in developing seeds, and some in young leaves
What molecules can GA be conjugated with
other organic molecs - glucose
Processes controlled by GA
Photperiodism – Day length effects flowering in some plants
GA is synthesized during long days
Bolting - Cabbage plants, rosette forms under short day, undergo stem elongation and flowering only under long days.
Application of GA induces bolting.
How does GA compare to auxins
not polar, not at tips