stem cells

Question 1

before the blastocust forms what happens?

Answer 1

cleavage –> morula (hollow) –> blastocyst (trophoblast, blastocoel, inner cell mass)

Question 2

what happens at day 6?

Answer 2

blostocyst hatches from zona pellucida and implants into uterine wall. epiblast and hypoblast form (bilaminar disc)

Question 3

what happensa t day 8?

Answer 3

blastocyst partially in uterus
amnionic cavity forms.
cytiotrophoblast and syncytiotrophoblast form

Question 4

what happens at day 10?

Answer 4

blastocyst fully in.
trophoblastic lacunae (placenta)
hypoblast forms extra embryonic mesoderm, which goes on to form the yolk sac.

Question 5

define: gastrulation

Answer 5

rapid proliferation and movement of cells. epiblast forms germ layers.

Question 6

how do 3 germ layers form

Answer 6

ectoderm formed not on primitive groove.
endoderm displaces hypoblast.
mesoderm goes on top of endoderm

Question 7

what cells differentiate from the endoderm, mesoderm and ectoderm

Answer 7

endoderm: skin, neural, some connective tissue
ectoderm: epithelial tissue of respiratory tract, gut, liver, pancreas, bladder, thymus
mesoderm: everything else bish

Question 8

what are stem cells

Answer 8

• undifferentiated cells
• self renew via mitosis
• differentiates into one or more types of specialised cells.

Question 9

3 potencies?

Answer 9

totipotent - can form whole organism (zygote)
pluripotent - forms all cells that come from 3 germ layers (embryonic stem cells)
multipotent - differentiates into many cells, but not all offered by the 3 germ layres

Question 10

3 types?

Answer 10

adult stem cells
induced pluripotent
embryonic

Question 11

describe embryonic stem cells

Answer 11

differentiate into all tissues.
inner cell mass
diff conditions = different cells

Question 12

describe induced pluripotent

Answer 12

adult differentiated cells
4 transcription factors added which go to pluripotent
diff conditions = diff cells.