In the following pedigree shows the segregation of two different recessive traits.

Assuming that both traits are 10 cM apart on the X chromosome, what is the probability that a female child will have both recessive traits?

TLS Online TPP Program

#Question id: 14738

#Unit 4. Cell Communication and Cell Signaling

Choose correct statements about Muscarinic receptors;

a. An acetylcholine analog, In activated condition, these receptors slow the rate of heart muscle contraction.

b .This type of receptor is coupled to a Gαi protein, and ligand binding leads to the opening of an associated K+ channel.

c .The subsequent influx of K+ ions from the cytosol causes an increase in the magnitude of the usual inside-negative potential across the plasma membrane that lasts for several seconds. 

TLS Online TPP Program

#Question id: 14739

#Unit 4. Cell Communication and Cell Signaling

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: 14740

#Unit 4. Cell Communication and Cell Signaling

Rod cells sense light with the aid of a light-sensitive GPCR known as rhodopsin; choose incorrect statements

a. Rhodopsin consists of the protein opsin, which has the usual seven–transmembrane segment GPCR structure, covalently linked to a light-absorbing pigment called retinal. 

b. Rhodopsin, found only in rod cells, is localized to the thousand or so flattened membrane disks that make up the inner segment of each of these rod-shaped cells.

c. A human rod cell contains about 4 × 10⁷ molecules of rhodopsin. 

d. The heterotrimeric G protein coupled to rhodopsin, called transducin (Gt), contains a Gα unit referred to as Gαt; like rhodopsin, Gαt is found only in rod cells.

TLS Online TPP Program

#Question id: 27107

#Unit 4. Cell Communication and Cell Signaling

Which of the following receptors is not a signalling receptor?

TLS Online TPP Program

#Question id: 27108

#Unit 4. Cell Communication and Cell Signaling

The receptor for adrenaline is a

TLS Online TPP Program

#Question id: 27109

#Unit 4. Cell Communication and Cell Signaling

Main protease subunit of gamma secretase?