Kaplan Ch. 3 - Embryogenesis

Question 1

Stem cell

Answer 1

Cells that have not yet differentiated or that give rise to other cells that will differentiate

Question 2

Totipotent

Answer 2

Includes only embryonic stem cells, can differentiate into any kind of cell type

Question 3

Pluripotent

Answer 3

Cells can differentiate into any cell type EXCEPT those that are found in placental structures (blastulation, gastrulation)

Question 4

Multipotent

Answer 4

Can differentiate into multiple types of cells within a particular group, adult stem cells are multipotent

Question 5

Autocrine cell - cell communication

Answer 5

The signal released by the inducer cell acts in itself

Question 6

Paracrine cell-cell communication

Answer 6

Signals act on cells in local area

Question 7

Juxtacrine cell-cell communication

Answer 7

Inducer cell directly stimulates receptors of adjacent responder cell

Question 8

Endocrine cell-cell communication

Answer 8

Secreted hormones from inducer travel via blood stream to responder cells in distant target tissues

Question 9

Growth factor

Answer 9

Peptides that promote differentiation

Question 10

How are nutrients transmitted from the mother to the fetus?

Answer 10

Diffusion (gradients) : example - [oxygen] is greater in maternal blood than fetal blood —> promotes diffusion of oxygen from maternal blood supply to fetal blood supply

Question 11

How does the placenta offer immune protection?

Answer 11

Many pathogens are too large to cross the placental barrier via diffusion. Also, antibodies are diffused across placenta to fetus because fetus is not capable of making own antibodies yet.

Question 12

Key concept: where does gas exchange occur in fetus?

Answer 12

The placenta