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TLS Online TPP Program

#Question id: 1257

Following statements are regarding to protein kinase A which phosphorylates multiple intracellular target proteins expressed in different cell types.

A. Inactive PKA is a tetramer consisting of two regulatory (R) subunits and two catalytic (C) subunits.

B. Each R subunit contains a pseudo-substrate domain whose sequence resembles that of a peptide substrate and binds to the active site in the catalytic domain but is not phosphorylated; thus the pseudo-substrate domain inhibits the activity of the catalytic subunits.

C. active PKA is turned off by binding of cAMP Each R subunit has two distinct cAMP-binding sites, called CNB-A and CNB-B.

D. Binding of cAMP by an R subunit of PKA occurs in a cooperative fashion; that is, binding of the first cAMP molecule to CNB-B increases the Kd for binding of the second cAMP to CNB-A. Thus small changes in the level of cytosolic cAMP can cause proportionately large changes in the number of dissociated C subunits and, hence, in cellular kinase activity.

Which of the following statements are incorrect?

#Unit 4. Cell Communication and Cell Signaling

  1. A, B and C

  2. B and C

  3. C and D

  4. B only

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TLS Online TPP Program

#Question id: 19079

#Unit 6. System Physiology – Plant

Pathogen evades plant by penetration of surface layers directly using mechanical pressure or enzymatic attack, some pass through natural openings, such as stomata or lenticels, and others only enter through wounded tissue. Once inside the plant, one of three main attack strategies is deployed specific feature of interaction given;
A) Necrotrophy
B) Biotrophy
C) Hemibiotrophy
i) where the plant cells remain alive throughout infection
ii) where the plant cells are killed in advance of infection 
iii) extensive plant tissue damage at initial stages
iv) where the pathogen initially keeps cells alive but at later stages of the infection, kills them
Match the following
TLS Online TPP Program

#Question id: 19080

#Unit 6. System Physiology – Plant

Which type of pathogens produces cell wall‐degrading enzymes tend to attack a broad range of plant species?
TLS Online TPP Program

#Question id: 19081

#Unit 6. System Physiology – Plant

Oomycetes (fungus‐like organisms), brown algae and mammalian parasites as Plasmodium falciparum and fungi can be__
a) Biotrophic plant pathogens
b) Necrotrophic plant pathogens
c) Hemibiotrophic plant pathogens
TLS Online TPP Program

#Question id: 19082

#Unit 6. System Physiology – Plant

Some necrotrophs produce host‐selective toxins as toxin that are active in only a few plant species; produced by the fungal pathogen Cochliobolus carbonum of maize (Zea mays) inhibits Plant enzyme such as___
TLS Online TPP Program

#Question id: 19083

#Unit 6. System Physiology – Plant

Alternaria produces a toxin, which activates a plant cell death program in tomato (Solanum lycopersicum) leaves___
TLS Online TPP Program

#Question id: 19084

#Unit 6. System Physiology – Plant

ToxA is produced by__
a) Cochliobolus carbonum
b) Stagonospora nodorum
c) Pyrenophora tritici‐repentis
d) fungus Botrytis
Which combination is correct?