Early Embryology Flashcards

1
Q

Where does fertilization take place?

A

Ampulla of the uterine tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What processes must sperm undergo to be able to fertilize the egg?

A

Capacitation and acrosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Female pronucleus

A

Formed after sperm has entered the egg via meiosis II of the oocyte’s nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Male pronucleus

A

Formed by enlargement of the sperm’s nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

When and what is cleavage?

A

Occurs about 30 hrs post-fertilization, and is the cell division to form the blastocyst

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Morula

A

when the cell have reached about 16-32 cells from division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What layers does the blastocyst separate into?

A

Embryo proper (inner cell mass) and Trophoblast (outer cell mass)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What portion of the trophoblast penetrates into the endothelium?

A

Syncyiotrophoblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is the extraembryonic mesoderm and what is it derived from?

A

Forms between the inner surface of the cytotrophoblast and outer surface of the amnion/exocoelomic membrane, and is derived from the umbilical vesicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is the chorionic cavity (extraembryonic cavity) formed?

A

Large cavities form in the extraembryonic mesoderm to form the cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What 2 layers does the extraembryonic mesoderm form?

A

Extraembryonic somatic mesoderm and extraembryonic splanchnic mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hydatidiform Mole

A

Trophoblast forms placenta membranes, but no embryonic development. Secretes high levels of hCG and may become malignant. Most arise from fertilization of an oocyte with no nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Placenta Previa

A

Placenta forms over the cervix, causing severe and possibly life-threatening bleeding later in pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Placenta percreta

A

Chorionic villi penetrate the myometrium all the way to the perimetrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Placenta Accrete

A

Abnormal adherence of placenta to the myometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Ectopic pregnancy

A

Implantation of blastocyst outside of the uterus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Gastrulation

A

Process of establishing trilaminar germ disc. Cells slip underneath the epiblast forming the primitive streak

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

3 primary germ layers

A

ectoderm, mesoderm, endoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Mesoderm

A

Forms the paraxial/lateral/intermediate mesoderms

20
Q

Ectoderm

A

Forms the neuroectoderm and neural crest cells

21
Q

Primitive node

A

Cephalic end of primitive streak surrounding the primitive pit

22
Q

Nodal gene

A

establishes the primitive streak, which is the body axis

23
Q

Fate map: Cranial region cells

A

Turn into notochord

24
Q

Fate map: Intraembryonic mesoderm

A

turns into Paraxial mesoderm

25
Fate map: Intermediate mesoderm
Turns into lateral plate of mesoderm
26
Fate Map: Extraembryonic mesoderm
Continuous with the lateral mesoderm
27
Growth of embryonic disc
w3: cephalic region broadens and differentiates w4: caudal region differentiates, primitive streak regresses
28
Embryonic period
w3-8: Organogenesis, cranio/caudal/lateral folding, vasculogenesis
29
Derivates: Ectoderm
CNS, PNS, eyes, epithelial skin, neural plate
30
Derivatives: Paraxial Mesoderm
Bones, tendons, cartilage, muscles, dermis of skin
31
Derivative: Intermediate mesoderm
Urogenital
32
Derivates: lateral mesoderm
Parietal: serous membrane that lines the body cavity Visceral: membranes around the organs
33
Endoderm
GI and epithelium of the organs
34
When do most large structural defects occur?
Weeks 3-8
35
Holoprosencephaly
aka fetal alcohol syndrome– high doses of EtOH kill the anterior midline, creating craniofacial structure deficiencies
36
Sirenomelia
Caudal region has insufficient mesoderm, impacting lower limb/vertebral/urogential development
37
Situs inversus
Left and right organ positions are switched
38
Sacrococcygeal teratoma
Remnants of the primitive streak proliferate, forming a teratoma on the new borns coccygeal region. Is the most common type of tumor in new borns
39
Weeks 9-12 of fetal development
External genitalia is formed, liver is main site of erythropoiesis
40
Weeks 13-16 of fetal development
Rapid growth, limb movement, face forms, ovaries have oogonia
41
Weeks 17-20 of fetal development
Movements can be felt by mom, CRL size increases another about 50mm
42
Weeks 21-25 of fetal development
Sucking movements begin, fetus reacts to sound, surfactant is beginning to be secreted at 24w
43
Weeks 25-29 of fetal development
Higher survival rate, erythropoiesis switches to the bone marrow
44
Weeks 30-34 of fetal development
Pupillary light reflex, 32+w usually survive
45
Weeks 35-38 of fetal development
CRL:36cm, CHL:50cm, weight:3-3.4kg