TLS Online TPP Program

#Question id: 370


Which of the following statements is true about buffer solutions?

#Unit 1. Molecules and their Interaction Relevant to Biology
  1. They maintain a constant pH of 7.

  2. They maintain a constant pH when acids are added to them but not when bases are added to them.

  3. They fluctuate in pH when either acids or bases are added to them.

  4. They maintain a relatively constant pH when either acids or bases are added to them.

More Questions
TLS Online TPP Program

#Question id: 15528

#Unit 4. Cell Communication and Cell Signaling

The B7 family of protein interact  with distinct receptor present on the T-cells, 

TLS Online TPP Program

#Question id: 15527

#Unit 4. Cell Communication and Cell Signaling

CD4 and CD8 T cells leave the thymus and enter the circulation as resting cells in which stage of the cell cycle?

TLS Online TPP Program

#Question id: 15526

#Unit 4. Cell Communication and Cell Signaling

If a thymocyte randomly generated a TCR with an affinity for MHC Class I, the TCR and CD8 would bind MHC Class I together, and generate a signal that specifically initiated a program that is 
a) silenced CD8 expression
b) silenced CD4 expression
c) induced expression of genes specific for helper T-cell lineage function
d) induced expression of genes specific for cytotoxic T-cell lineage function

TLS Online TPP Program

#Question id: 15525

#Unit 4. Cell Communication and Cell Signaling

In the instructive model, TCR/CD4 and TCR/CD8 coengagement generates unique signals, if a thymocyte randomly generated a TCR with an affinity for MHC Class I. which thymocyte would bind with MHC class I?

TLS Online TPP Program

#Question id: 15524

#Unit 4. Cell Communication and Cell Signaling

The bulk of DP thymocyte death (~95%) occurs among thymocytes that fail positive selection because 

TLS Online TPP Program

#Question id: 15523

#Unit 4. Cell Communication and Cell Signaling

The appearance of ϒδ thymocytes and αβ thymocytes during mouse fetal development. Fetal animals generate
a) more αβ T-cells than ϒδ T-cells
b) the proportion of ϒδ T-cells generated drops off dramatically after birth
c) the proportion of αβ T-cells generated drops off dramatically after birth
d) more ϒδ T-cells than αβ T cells