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TLS Online TPP Program

#Question id: 19480

The C-terminal half of these cry proteins is highly conserved and is most likely involved in the 

#Unit 12. Applied Biology
  1. Dimer formation
  2. Globule formation
  3. Lattice formation
  4. Crystal formation
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TLS Online TPP Program

#Question id: 10413

#Unit 1. Molecules and their Interaction Relevant to Biology

Following are certain statements are related to the effect of red and far-red light;
a) under a dense canopy much of the red light is absorbed by plant pigments, resulting in transmittance of mostly far-red light
b) Pr (red) has highest photon flux at 680 nm while Pfr (far-red) has highest photon flux at 730nm
c) Pfr far-red light–absorbing form, which is considered to be the physiologically active form of phytochrome
d) R:FR ratio is strongly affected by the presence of a canopy because chlorophyll absorbs far-red but not red light
Which one of the combinations of above statements is incorrect?
TLS Online TPP Program

#Question id: 11840

#Unit 1. Molecules and their Interaction Relevant to Biology

During an ethylene signalling pathway, what will have done  inside cytosol and nucleus . Given below some prediction about presence and absence of ethylene in column B match with column A

            COLUMN A

                                           COLUMN B

I-  In the presence of ethylene

a)  ETR1 signaling is repressed and CTR1 is inactive

II- In the absence of ethylene

b)  ETR1 activate CTR1, a Ser/Thr kinase

 

c)  CTR1 phosphorylates the C-terminal domain of EIN2

 

d)  The nonphosphorylated C terminus of EIN2 is cleaved by a protease

 

e)  Phosphorylation of EIN2 inhibits proteolytic cleavage

 

f)  EIN3 transcription factors are ubiquitinated and degraded in the nucleus by the 26S proteasome

 

g)  EIN3 initiates a transcriptional cascade by activating expression of ethylene-responsive genes, including ERF1 transcription factor, leading to ethylene responses

 
TLS Online TPP Program

#Question id: 2253

#Unit 1. Molecules and their Interaction Relevant to Biology

Match the following lipid linked proteins (column I) with their function (Column II).

Column I

Column II

A. prenylated proteins

i. These proteins are located in a number of subcellular compartments, including the cytosol, the endoplasmic reticulum, the inner face of the plasma membrane, and the nucleus.

B. fatty acylated proteins

ii. The core structure of these proteins consists of phosphatidylinositol glycosidically linked to a linear tetrasaccharide composed of three mannose residues and one glucosaminyl residue.

C. glycosylphosphatidylinositol-linked proteins

iii. The proteins that have covalently attached lipids that are built from isoprene units

TLS Online TPP Program

#Question id: 29440

#Unit 1. Molecules and their Interaction Relevant to Biology

Nitrogenase is a complex consisting of the 
(a) MoFe protein (dinitrogenase or component I) a heterotetramer
(b) the Fe protein (dinitrogenase reductase or component II) a heterotetramer
(c) MoFe protein (dinitrogenase or component I) a homodimer.
(d) the Fe protein (dinitrogenase reductase or component II) a homodimer

Which of the following is correct 
TLS Online TPP Program

#Question id: 4423

#Unit 1. Molecules and their Interaction Relevant to Biology

Each repeat unit within the nuclear ribosomal gene cluster of eukaryotes (rDNA) contains
TLS Online TPP Program

#Question id: 10308

#Unit 1. Molecules and their Interaction Relevant to Biology

Oxidative decarboxylation of pyruvate to acetyl-CoA by the PDH complex, how the pyruvate dehydrogenase complex carries out the five consecutive reactions in the decarboxylation and dehydrogenation of pyruvate?

 A) Pyruvate reacts with the bound thiamine pyrophosphate (TPP) of pyruvate dehydrogenase, undergoing decarboxylation to the hydroxyethyl derivative

 B) A transesterification in which the —SH group of CoA replaces the —SH group of E2 to yield acetyl-CoA and the fully reduced (dithiol) form of the lipoyl group

 C) The reduced FADH2 of E3 transfers a hydride ion to NAD1 , forming NADH, the enzyme complex is now ready for another catalytic cycle

 D) The transfer of two electrons and the acetyl group from TPP to the oxidized form of the lipoyllysyl group of the core enzyme, dihydrolipoyl transacetylase, to form the acetyl thioester of the reduced lipoyl group

 E) Dihydrolipoyl dehydrogenase promotes transfer of two hydrogen atoms from the reduced lipoyl groups of E2 to the FAD prosthetic group of E3 , restoring the oxidized form of the lipoyllysyl group of E2

 Find out the correct sequence of action of this complex enzyme?