How the degradation of alkanes and aromatic hydrocarbons generally occurs.

1. Oxygenase enzyme

2. β-oxidation to yield acetyl CoA

3. Hydrogenation reaction

4. Carboxylation

Which of the following are correct?

#Question id: 11814

#Unit 6. System Physiology – Plant

Simplified biosynthetic pathway for cytokinin biosynthesis followed given such steps;

a) isopentenyl transferase (IPT), is the addition of the isopentenyl side chain from DMAPP (dimethylallyl diphosphate) to an adenosine moiety (AMP)

b) iPRTP or iPRDP is converted to ZTP or ZDP respectively by cytochrome P450 monooxygenase  and eventually is converted to zeatin

c) The ribotide and riboside forms of trans-zeatin can be interconverted, and free transzeatin can be formed from the ribotide by the LONELY GUY (LOG) family of cytokinin

Which of the following steps is true of the cytokinin biosynthesis?

#Question id: 11815

#Unit 6. System Physiology – Plant

Some given statements about  the cytokinin signalling pathway;

a)  Cytokinin receptor CRE1 probably functions as a monomer

b) Two other hybrid sensor kinases (AHK2 and AHK3) may also act as cytokinin receptors in Arabidopsis

c) Activated receptor activates their histidine kinase activity, The phosphate is transferred to an aspartate residue (D) on the fused receiver domains

d) The phosphate is then transferred to a conserved histidine present in an AHP protein that transfer the phosphate to an aspartate residue  located within the receiver domain of type-B ARRs only

e) The phosphorylation of the type-B ARR activates the output domain to induce transcription of genes encoding type-A ARRs.

f) The phosphorylated type-A ARRs feed back to negatively regulate cytokinin signaling, thus dampening cytokinin responses

Which of the following are the correct prediction about cytokinin signalling?

#Question id: 11816

#Unit 6. System Physiology – Plant

Which of the following given statements are correct predict about negatively regulate signalling pathway?

#Question id: 11817

#Unit 6. System Physiology – Plant

In the cytokinin pathway a phosphotransfer AHP1 protein is also known as___

#Question id: 11818

#Unit 6. System Physiology – Plant

Cytokinin signals to nuclear-localized response regulators  by transferring the phosphate group to an aspartate on the receiver domain of the ARR. The ARR response regulators are encoded by multigene families, They fall into two basic classes:

I) Type-A ARRs

II)Type-B ARRs

a) The products of which are made up solely of a receiver domain

b) Receiver domain also include an output domain containing DNA-binding  transcription activation sites

c) Which negatively regulate cytokinin signaling by interacting with other proteins in a manner dependent on the phosphorylation state

d) Which are activated by phosphorylation, which enables them to regulate the transcription of a set of target genes

e) Which are targeted by F-box proteins called KISS ME DEADLY (KMD) proteins negatively regulates the cytokinin response

Which of the following are the correct explanation of the given ARRs types  classes of response regulator?

#Question id: 11819

#Unit 6. System Physiology – Plant

Ethylene is a gaseous hormones which  shows typical  triple response. Following are certain statements regarding the triple response:

a) reduced stem elongation

b) increased lateral growth (swelling)

c) promote root elongation

d) exaggeration of apical hook

Which one of the following combinations is correct?