Factors that promote tolerance rather than stimulation

a. High doses of antigen

b. Long-term persistence of antigen in the host

c. Intravenous or oral introduction

TLS Online TPP Program

#Id: 6984

#Unit 5. Developmental Biology

If a stem cell divides symmetrically, have the ability to produce either two stem cells (increasing the stem cell pool by one) or two committed cells (decreasing the pool by one). This is called symmetrical renewing or symmetrical differentiating.

TLS Online TPP Program

#Id: 6985

#Unit 5. Developmental Biology

TLS Online TPP Program

#Id: 6986

#Unit 5. Developmental Biology

If a stem cell divides asymmetrically, produce two types of cells (a stem cell & a developmentally committed cell) are produced at each division, is called the single stem cell asymmetry.

TLS Online TPP Program

#Id: 6987

#Unit 5. Developmental Biology

Cell potency is a cell’s ability to differentiate into other cell types. Stem cell has the power, or potency, to produce many different types of differentiated cells.

TLS Online TPP Program

#Id: 6988

#Unit 5. Developmental Biology

The potency of a cell is an intrinsic property and is greater than or equal to its fate. Potency is described as the gene activation potential within a cell which begins with – 

Totipotency, Pluripotency, Multipotency  and finally Unipotency.

TLS Online TPP Program

#Id: 6989

#Unit 5. Developmental Biology

Totipotency

the ability of a single cell to divide and produce all of the differentiated cells in an organism (embryonic and extra embryonic cells).

Eg- spores and zygotes