The axis of the primitive streak is equivalent to the dorsal-ventral axis of amphibians.

TLS Online TPP Program

#Id: 7001

#Unit 5. Developmental Biology

When a multipotent stem cell divides asymmetrically, its maturing daughter cell often goes through a transition stage as a progenitor or transit-amplifying cell, as is seen in the formation of blood cells, sperm, and neurons.

TLS Online TPP Program

#Id: 7002

#Unit 5. Developmental Biology

Progenitor cells are not capable of unlimited self-renewal; rather, they have the capacity to divide only a few times before differentiating.

TLS Online TPP Program

#Id: 7003

#Unit 5. Developmental Biology

Although limited but Progenitor cells proliferation serves to amplify the pool of progenitors before they terminally differentiate.

TLS Online TPP Program

#Id: 7004

#Unit 5. Developmental Biology

Cells within progenitor pool can mature along different but related paths of specification.

TLS Online TPP Program

#Id: 7005

#Unit 5. Developmental Biology

 Precursor cell, is widely used to denote any ancestral cell type (either stem cell or progenitor cell) of a particular lineage; it is often used when such distinctions do not matter or are not known.

TLS Online TPP Program

#Id: 7006

#Unit 5. Developmental Biology

Some adult stem cells, such as spermatogonia, are referred to as unipotent stem cells because they function in the organism to generate only one cell type.