Oxygen-Evolving Organisms Have two Photosystems that Operate in Series, explain by emerson that is the Photosystem I preferentially absorbs far-red light of wavelengths greater than 680 nm; photosystem II preferentially absorbs red light of 680 nm and is driven very poorly by far-red light; Another difference between the photosystems is that,

a.) Photosystem I produces a strong reductant, capable of reducing NADP+, and a weak oxidant

b.) Photosystem I produces a very strong oxidant, capable of oxidizing water, and a weaker reductant than the one produced by photosystem II

c.) Photosystem II produces a strong reductant, capable of reducing NADP+, and a weak oxidant

d.) Photosystem II produces a very strong oxidant, capable of oxidizing water, and a weaker reductant than the one produced by photosystem I

Which statements would be CORRECT?

TLS Online TPP Program

#Question id: 13161

#Unit 4. Cell Communication and Cell Signaling

Which of the following mechanism depends on the activation of heterotrimeric G proteins?

TLS Online TPP Program

#Question id: 13160

#Unit 4. Cell Communication and Cell Signaling

According to the Switching mechanism, monomeric G proteins exist in two states. Match the following states (Column I) with correct mechanism (Column II).

Column I	Column II
A. “ON” state	i. switch I and switch II, are bound to the terminal γ phosphate of GTP through interactions with the backbone amide groups of conserved threonine and glycine residues.
B. “OFF” state	ii. GTPase-activating proteins
	iii. guanine nucleotide exchange factor
	iv. Due to the removal of the γ phosphate by GTPase-catalyzed hydrolysis causes switch I and switch II to relax into a different conformation

TLS Online TPP Program

#Question id: 13159

#Unit 4. Cell Communication and Cell Signaling

How signaling is involved in ensuring that yeast cells fuse only with cells of the opposite mating type?

TLS Online TPP Program

#Question id: 1262

#Unit 4. Cell Communication and Cell Signaling

Although MAP kinase is often activated in multicellular animals by RTKs or cytokine receptors, signaling from other receptors can activate MAP kinase in other eukaryotic cells. we consider the mating pathway in the yeast S. cerevisiae, a well-studied example of a MAP kinase cascade linked to G protein–coupled receptors (GPCRs). Which of the following statement is incorrect?

TLS Online TPP Program

#Question id: 1261

#Unit 4. Cell Communication and Cell Signaling

A FOXO3a mutant in which the three serine residues that are targets for PKB are mutated to alanine then what will be the result?

TLS Online TPP Program

#Question id: 1260

#Unit 4. Cell Communication and Cell Signaling

Which of the following statement regarding RTK/Ras pathway is incorrect?