The first step in polar transport is auxin influx. According to the model, auxin can enter plant cells from any direction by either of two mechanisms:

a) Passive diffusion of the protonated (IAAH) form across the phospholipid bilayer

b) Secondary active transport of the dissociated (IAA–) form via a 2H+–IAA– symporter

c) Active diffusion of the protonated (IAAH) form across the phospholipid bilayer

Find out the correct statements of about diffusion of IAA.

TLS Online TPP Program

#Question id: 29452

#Unit 6. System Physiology – Plant

Auxins in biological samples can be determined by

a. bioassay

b. mass spectrometry

c. enzyme-linked immunosorbent assay 

d. The Avena coleoptile curvature assay

TLS Online TPP Program

#Question id: 29453

#Unit 6. System Physiology – Plant

Which of the following technique will be most effective for IAA concentrations of about 0.02 to 0.2 mg L–1

TLS Online TPP Program

#Question id: 29454

#Unit 6. System Physiology – Plant

Identify A, B and C in auxin synthesis

a. Tryptophan (Trp)----------A-------------→ Indole-3-pyruvic acid 

b. (IPA) -----------B------------→ Indole-3-acetaldehyde (IAld)

c. Indole-3-acetaldehyde (IAld) ------------C-----------→ I3AA

TLS Online TPP Program

#Question id: 29455

#Unit 6. System Physiology – Plant

which of the following auxin derivates compound that provide broad‐spectrum control of fungal pathogens

TLS Online TPP Program

#Question id: 29456

#Unit 6. System Physiology – Plant

In maize kernels, IAA also appears to be synthesized by a tryptophan independent pathway via

TLS Online TPP Program

#Question id: 29457

#Unit 6. System Physiology – Plant

Covalent conjugation of amino acids to IAA can also result in permanent inactivation (storage or degradation), here certain combination is given (∧ shows conjugation)

a. IAA ∧ myo-inositol/Gluc/Ala/Leu/Me ---Reversible (storage)

b. IAA ∧ myo-inositol/Gluc/Ala/Leu/Me ---irreversible (degradation)

c. IAA ∧ oxIAA/GH3-Asp-Glu/3-Methyleneoxidole ---Reversible (storage)

d. IAA ∧ oxIAA/ GH3-Asp-Glu/3-Methyleneoxidole---irreversible (degradation)

Which of the following is correctly paired