Cell Specialization

cell differentiation

when a cell forms a different cell type by expressing certian genes and not others

plant differentiation - when

adult

animal differentiation - when

early embryo

Apical meristems

causes primary growth (shoots and roots)

Lateral meristems

causes secondary growth

zygote

first cell when sperm and egg fuse

blastocyst

fluid filled ball of cells at implantation

emrbyo

organism in earliest stages of growth

morphogens

control gene expression (extracellular), concentration affects fate of cell

stem cell

undiffernetiated cell capable of unlimited differentiation

embryonic stem cell

undifferentiated cell in early-stage embryo capable of continual cell division

differences between embryonic stem cells and adult stem cells

embryonic are pluripotent, adult are multipotent

stem cell niche

microenvironments that either maintain stem cells or promote their replication and differentiation. ex: bone marrow, hair follicles

HSC

haemapoietic niche contains stem cells that produce red blood cells, white blood cells, and platelets

hair follicle stem cell niche

contains bugle hair follicle stem cells which regenerate hair follicle and hair

totipotent

can become any cell and placenta (first cells of a zygote)

pluripotent

can become any cell but not placenta (blastocyst)

multipotent

can become several related cell types, but not all (adult)