In heart muscle, activation series of the muscarinic acetylcholine receptor its effector K+ channel via the Gβγ subunit of a Gi protein.

a. Binding of acetylcholine triggers activation of the Gαi subunit and its dissociation from the Gβγ subunit in the usual way. 

b. The released Gβγ subunit (rather than Gαi∙GTP) binds to and opens the associated effector protein, a K+ channel. 

b. The increase in K+ permeability hyperpolarizes the membrane, which reduces the frequency of heart muscle contraction. 

d. Activation is terminated when the GTP bound to Gαi is hydrolyzed (by a GAP enzyme that is an intrinsic part of the Gαi subunit) to GDP and Gαi∙GDP recombines with Gβγ.

TLS Online TPP Program

#Question id: 26444

#Unit 3. Fundamental Processes

global genome repair (GG-NER) depending on proteins

TLS Online TPP Program

#Question id: 26443

#Unit 3. Fundamental Processes

XP-V is caused by a defect in the translesion DNA polymerase

TLS Online TPP Program

#Question id: 26441

#Unit 3. Fundamental Processes

NER component and their functions are given, match them correctly

Component	Function
1. UvrA	a. DNA Pol I and DNA ligase
2. UvrB dimer	b. creates two incisions
3. UvrC	c. melts the DNA to create a single-stranded bubble around the lesion
4. DNA Pol I and DNA ligase	d. scanned Distortion

TLS Online TPP Program

#Question id: 26440

#Unit 3. Fundamental Processes

Choose the correct statement 

a. Long patch repair system is accomplished by Lig1, FEN1, Pol ζ ε, and APE1 

b. Long patch repair system is accomplished by Lig3, FEN1, Pol ξ β ,APE1 & lyase action

c. Short patch repair system is accomplished by Lig3, FEN1, Pol  ξ β,APE1 & lyase action

d. Short patch repair system is accomplished by Lig1, FEN1, Pol ζ ε, , and APE1

TLS Online TPP Program

#Question id: 26439

#Unit 3. Fundamental Processes

Which of the following Mut system involve in the rectification of oxygen damage

TLS Online TPP Program

#Question id: 26438

#Unit 3. Fundamental Processes

 Preferential removal of bases in pairs that have oxidized guanine is designed to minimize mutations using different Mut system having specific functions match them correctly

Mut system	Mutational pairing
1. MutT	a. removes G=O that is paired with C
2. MutM	b. removes A that is paired with G=O
3. MutY	c. hydrolyzes 8-oxo-dGTP