Week 3- Embryonic period Flashcards Preview

Developmental Bio > Week 3- Embryonic period > Flashcards

Flashcards in Week 3- Embryonic period Deck (22):
1

embryonic period

weeks 3-8
all body systems will structurally develop
none are fxnl except the card. sys
shape of the embryo changes (more human)

2

three phases to embryonic devl

growth (cell division)
morphogenesis ( dev. of form and includes mass cell movements- make heart, lungs etc)
differentiation (maturation of physiological processes, give the cells specific functions)

3

trilaminar embryo

dorsal, ectoderm
ventral endoderm
middle- mesoderm
made during gastrulation

4

ectoderm

1. neuroectoderm which gives rise to all CNS (brain and spinal cord) and PNS (all autonomic NS)

2. Epidermal covering (all body and all their derivatives)

5

neural plate

edges fold up and neural groove is formed, notochord underneath

6

neuralation

the formation of the neural tube

7

cranial neuropore and caudal neuropore

openings at ends of neural tube- close on specific days (cranial 25 and caudal 27/8)

8

BMP4

is a ubiquitous neural protein, induces neural plate

9

neural crest cells

super smart and moveable cells that make the connective tissue of the mesoderm, all of the PNS, line up the heart with its arteries, forms portions of your teeth, face, neck, dermis, adrenal medulla, schwann cells in PNS, melanocytes

10

epidermal covering

makes pretty much all other tissue
epidermis, sweat glands, sebaceous glands, mammary etc

11

axial mesoderm

makes notochord, precordal plate, caudal eminence (loss of primitive node)

12

paraxial mesoderm

makes somitomeres in the head, precursor to somites.
in head: they make portions of neuroplate to form neuromeres (first 7 somitomeres)
In body: somitomeres-> somites, move occitpital to caudal, can determine age of the embryo
somites form sclerotome- ribs, vertebrae,base of skull
forms dermatomyotome

13

sclerotome

vertebrea, ribs, base of skull

14

dermatome

dermis of skin

15

myotome

skeletal muscles of the body and limbs

16

intermediate mesoderm

forms most organs, smooth muscles and epithelial linings, both urinary and genital systems

17

embryonic folding

1. cephalocaudal folding- primitive streak and notochord establish a cephalocaudal axis, right side left side and dorsal ventral surface

-rapid head and tail growth causes the embryo to curl toward the ventral surface (primarily the neural tube causes cephalic folding)

18

lateral plate mesoderm

proliferation of LPM brings the ectoderm to the ventral surface, found in the body not the head
body splits into two arms:
1. somatic- to body wall (skin, muscle, cartilage, connective tissue)
2. splanchnic- goes around the 2* yolk sac (lines all endoderm-lined organs and all tissues of Card.Sys)

19

lateral folding

endoderm becomes folded into a long narrow tube within the embryo
mesoderm continues to separate out ectoderm from endoderm
ectoderm and amniotic cavity completely encircle the embryo, ectoderm forming the outer covering of the embryo

20

intraembryonic cavity

the cavity formed with the LPM closes off the ventral side
it forms the thoracic cavity
it forms the abdominal cavity
have to have somewhere to put our organs!!

21

Extraembryonic mesoderm

mesodermal contribution to the chorion
partially for the maternal fetal circulation, because the fetus is getting bigger

22

endoderm tube

pinched off yolk sac lined internally with endoderm
forms into the specific organs of the GI system
also makes portions of the pharynx and lungs, buds of liver, pancreas, gall bladder