Term
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Definition
aka embryonic period
when each of the germ layers gives rise to tissues |
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Term
| when have all the main organ systems been established |
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Definition
| by the end of the embryonic period |
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Term
| when are the external features of the body noticable |
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Definition
| the end of the second month |
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Term
| descbe the process of neurlation |
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Definition
1. neural plate formation induces neuroectoderm
2. the neural plate elongates
3. lateral edges of plate elevate and meet at the midline
4. edges fuse into a tube |
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Term
| cranial and caudal neuropores |
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Definition
| the openings at the end of the neural tube communicate with the amniotic cavity with these pores |
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Term
| when does the cranial neuropore close |
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Definition
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Term
| when does the caudal neuropore close |
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Definition
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Term
| when is the neural tube completely closed |
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Definition
| day 27 when both neuropores close and when dilations (brain vessicles) form in the cephalic region |
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Term
| describe the movement of formation of the neural tube |
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Definition
| begins in cervical area and forms bidirectionally from there |
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Term
| neural crest cell formation |
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Definition
1. cells from the lateral border (crest) of the neural plate break away while the neural tube is forming
2. the cells change from epithelial to mesenchymal
3. BMP induces the formation, migration, proliferation, and differentation of the neural crest cells |
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Term
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Definition
| loosly organized embryonic connective tissue regardless of the origin |
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Term
| where are all ganglia formed |
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Definition
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Term
| the neural crest forms the following... |
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Definition
all ganglia
connective tissue and bones of face and scull
C cells of thydoid
conotruncal seprum of the heart
odontoblasts
dermis of face and neck
adrenal medulla
schwann cells
glial cells
meninges of the forebrain
melanocytes
smooth muscle cells of blood vessels in the face and forebrain |
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Term
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Definition
neural tube defect
fails to close at crainial end
leads to death, inability to swallow, usually still born |
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Term
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Definition
neural tube fails to close in the cervical region or down farther
the patient can live fine most of the time |
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Term
| how can neural tube defects be prevented |
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Definition
| mom takes folic acid 3mo to conception |
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Term
| what does the ectoderm develop into |
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Definition
| CNS, PNS, sensory epithelium of ears and nose, epidermis, hair, glands, nails, pituitary, tooth enamel |
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Term
| what does the mesoderm along the midline derive into |
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Definition
paraxial mesoderm on the sides of the axis
lateral plate mesoderm |
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Term
| what does the lateral plate mesoderm derive into |
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Definition
somatic / parietal mesoderm
splanchnic / visceral mesoderm |
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Term
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Definition
formed by the parietal and visceral mesoderm
later makes the thorasic and abdominal cavity |
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Term
| where is the parietal mesoderm located |
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Definition
| continous with mesoderm covering the amnion |
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Term
| what does the parietal mesoderm develop into |
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Definition
| thorasic pleura, abdominal pleura, peritoneium, serous membranes |
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Term
| where is the visceral mesoderm located |
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Definition
| continous with the yolk sac |
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Term
| what does the visceral mesoderm make |
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Definition
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Term
| what does the paraxial mesoderm make |
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Definition
unorganized somitomeres (first in cephalic)
later it maes organized somites which turn into muscle, dermis, skeletal, vertebre, ribs |
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Term
| where is the indermediate mesoderm located |
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Definition
| connects paraxial and lateral plate mesoderm |
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Term
| what does the intermediate mesoderm make |
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Definition
| urogenital, future nephrotones (segmental cell clusters), nephrogenic pores (unsegmented cell clusters), cervical to caudal regions, gonads, excretory units, mesonephros |
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Term
| what is a way to determine the age of an embryo |
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Definition
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Term
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Definition
1. VEGF activates hemangioblasts
2. hemangioblasts induce to form blood cells and blood islands (week 3)
3. blood islands form vessels |
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Term
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Definition
vascular endothelial growth factor
mesoderm secretes them so they induce hemangioblasts to do vasculogenesis |
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Term
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Definition
| vessels sprout from current vessels |
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Term
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Definition
| GI tract, the root of the yolk sac, gut tube, epithelial lining of: respiratory tract, gut, parathyroid, liver, pancreas, laticular stroma, bladder, urethra, tympanic cavity, auditory tube |
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Term
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Definition
foregut: cranial region
heind gut: tail region
midgut |
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Term
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Definition
| how the midgut temporairly communicates with the yolk sac via a broad stalk |
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Term
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Definition
| holds ectoderm and endoderm together, ruptures during week 7 making the anus |
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Term
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Definition
holds the ectoderm and endoderm together at the cephalic end
breaks down in week 4 connecting the amniotc cavity and the primitive gut
evuntally makes the mouth |
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Term
| timeframe where the baby is called am embryo |
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Definition
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Term
| timeframe where the baby is called a fetus |
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Definition
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