Morphogenesis, iPSCs

Question 1

1st main fate division in early embryonic development

Answer 1

ICM- embryo

trophoblast- extraembryonic tissue

Question 2

germ cells

Answer 2

source of sperm and eggs

Question 3

characteristics of germline stem cells

Answer 3

division is asymmetric

self- renewing

Question 4

oocyte division

Answer 4

1st division: 1 polar body, 1 egg cell
2nd division: 3 polar bodies, 1 haploid egg cell

arrested in meiosis I until ovulation

asymmetric

Question 5

sperm division

Answer 5

symmetric

diploid–> 2 divisions–> 4 haploid sperm

Question 6

When the follicle ruptures what happens

Answer 6

ovulation = release of egg into the fallopian tube and eventually turns into corpus lutem (secretes hormones to keep egg alive + pregnancy viable til placenta)

Question 7

corona radiata

Answer 7

outer layer of oocyte that protects it

Question 8

When does the sperm fertilize oocyte and where

Answer 8

1-4 days, in the fallopian tube

Question 9

Steps of fertilization

Answer 9

1) sperm breaks through corona radiata (if they have the correct proteins)
2) when that happens then the cortical granules enzymes break and the zona pellucida HARDENS to prevent multiple sperm from penetrating
3) second mitotic division happens once sperm hits
4) female and male pronuclei join

Question 10

After fertilization zygote becomes (a- 16 cells) then b

Answer 10

a- morula

b- blastocyst

Question 11

When does the cell become pluripotent in embryogenesis?

Answer 11

at blastocyst

before totipotent (zygote–> morula)

Question 12

Two main components of blastocyst and what they become

Answer 12

1) inner cell mass (ICM): embryo

2) trophoblast: extraembryonic tissue

Question 13

when does implantation occur

Answer 13

day 6

blastocyst implants in uterine wall

Question 14

ectopic pregnancy

Answer 14

blastocyst implants somewhere it shouldn’t (NOT uterine wall), often fallopian tube

Question 15

identical twinning

Answer 15

1) 2 blastocysts–> 2 trophoblasts–> 2 embryos, 2 amnion

2) 2 ICM–> 1 trophoblast–> 2 embryos, 1 amnion

Question 16

Inner cell mass (ICM) adopts 2 fates which are (a+b) and that together those make (c)

Answer 16

a) epiblast and b) hypoblast

and together make c) bilaminar embryo

Question 17

epiblast gives rise to

Answer 17

3 germ layers

amnion membrane

Question 18

hypoblast gives rise to

Answer 18

yolk sac endoderm

Question 19

Trophoblast differentiates to

Answer 19

cytotrophoblast and syncytiotrophoblast

Question 20

cytotrophoblast

Answer 20

outer sac, portions of placenta

Question 21

syncytiotrophoblast

Answer 21

blood supply, seek out vasculature

Question 22

gastrulation

Answer 22

process of generating the 3 germ layers (from epiblast)

Question 23

How the germ layers form

Answer 23

epithelial cell fate changes (epithelial to mesenchymal transition EMT), primitive streak forms on surface

endoderm comes from epiblast via EMT –> migrates to bottom and displaces hypoblast

mesoderm comes from epiblast via EMT in the middle past the primitive streak

then the top becomes ectoderm

Question 24

ectoderm gives rise to

Answer 24

neural tube( brain, spinal cord), skin

Question 25

mesoderm gives rise to

Answer 25

internal connective tissue, tissue, muscle

Question 26

endoderm gives rise to

Answer 26

lines yolk sac--> gut

Question 27

totipotency

Answer 27

gives rise to ALL cells and placenta

Question 28

pluripotency

Answer 28

gives rise to all 3 germ layers

Question 29

multipotency

Answer 29

differentiate into multiple cells or tissues

Question 30

unipotency

Answer 30

differentiate into single cell type (ie. germline stem cells)

Question 31

Embryonic stem cell properties

Answer 31

infinite self renewal, pluripotent (can make all 3 germ layers), taking ICM out of blastocyst and putting in dish ethical issues, technical issues

Question 32

Positives of induced pluripotent stem cells (iPSC)

Answer 32

not using embryos--> eliminate ethical concerns retains patient genetics (DNA) easy and cost-effective

Question 33

How can you make iPSCs

Answer 33

4 yamanaka transcription factors

Question 34

3 ways 4 yamanaka TFs are put into cells

Answer 34

adenovirus transduction retrovirus transduction plasmid transfection

Question 35

Where are iPSCs most commonly derived from? and what two are commonly for kids

Answer 35

most common from fibroblasts (skin cells via punch biopsy) kids: blood and urine

Question 36

why could isogenic lines be better than patient lines

Answer 36

genetically identical with the exception of disease gene((s), genome editing, so no genetic diversity confounding data good for rare diseases

Question 37

benefit of patient lines

Answer 37

could study multigenetic disorders

Question 38

biomedical questions that could be addressed with iPSCs

Answer 38

modeling disease drug safety stem cell therapies

Question 39

teratomas

Answer 39

germ cell tumors that can form differentiated cell types --> have bones, limbs, hair, etc in abnormal locations

Question 40

organoids

Answer 40

clumps of stem cells grown in 3-D