You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium. You have isolated a mutation that causes constitutive melibiase activity, which you designate MelA–. P1 phage mapping experiments using a Tn5 insertion linked to Mel1 show that MelA– is not linked to Mel1. Moreover you find that when an amber suppressor is introduced into a MelA– mutant, normal melibiase regulation is restored. Classify the MelA– mutation on the basis of genetic properties,  make a proposal for the type of regulatory functions affected by the MelA– mutation?

TLS Online TPP Program

#Question id: 14992

#Unit 4. Cell Communication and Cell Signaling

Given cell types contains granules, which perform different function such as;

CELL TYPE	MOLECULES IN GRANULE	FUNCTIONS
A) Neutrophil	i) Chemokines	a) Antiviral activity
B) Eosinophil	ii) Lipid mediators	b) Vasodilation
C) Basophil	iii) Antimicrobial proteins	c) Modulation of adaptive immune response
D) Mast cell	iv) Histamine	d) Regulation of inflammation
	v) Cytokines	e) Direct harm to pathogens
	vi) Ribonucleases

Match the given following  cells with their correct functions of granules?

TLS Online TPP Program

#Question id: 14993

#Unit 4. Cell Communication and Cell Signaling

CD-56 marker found on ?

TLS Online TPP Program

#Question id: 14994

#Unit 4. Cell Communication and Cell Signaling

The absence of MHC class I, which is expressed by almost all normal cells, but is specifically down-regulated by some tumors and in response to some viral infections, it will undergo apoptosis by

TLS Online TPP Program

#Question id: 14995

#Unit 4. Cell Communication and Cell Signaling

NKT Cells, which share features with both conventional T lymphocytes and NK cells,

Statement-I) Like T-cells, NKT Cells have T-cell receptors (TCRs), and some express CD4.

Statement-II) Like NK cells, NKT Cells have antibody receptors  

Statements-III) they are APCs

Given above statements, which is sharing correct features of NKT cells?

TLS Online TPP Program

#Question id: 15144

#Unit 4. Cell Communication and Cell Signaling

For the stimulation of B-cell responses

TLS Online TPP Program

#Question id: 15145

#Unit 4. Cell Communication and Cell Signaling

Which of the following drug causes autoimmune hemolytic anemia?