Shared Flashcard Set

Details

Limb Development
Medical School Devo
34
Other
Graduate
09/04/2011

Additional Other Flashcards

 


 

Cards

Term
What happen to the first 7 pairs of somitomeres? What about the other 37?
Definition
First seven become the striated muscle of the face, jaw, and throat. The rest become somites
Term
Skeletal muscle comes from where?
Definition
Paraxial mesoderm. Specifically the Myotome. These mesenchymal cells differentiate into Myoblasts then travel
Term
What is the signalling molecule that does dorsalizing signals for skeletal muscles?
Definition
Wnt. This will eventually lead to all the skeletal muscles of the back
Term
What is the signalling molecule that does ventral lateral signalling in skeletal muscle development?
Definition
BMP-4. This will give rise to all the skeletal muscles except for the back skeletal muscles
Term
What is the signalling molecule associated with early striated muscle development?
Definition
Pax3
Term
What is MyoD?
Definition
MyoD is a Helix-loop-helix transcription factor associated with development of muscle
Term
What is the name for the failure of the anterior abdominal musculature to form?
Definition
Prune Belly
Term
[image]
Identify what the terms mean
Definition
Melia: Limb
Dactyly: digit
Mero: Part of
Acro: Tip
Poly: Extra
Ectro: Missing
A: Missing
Brachy or Phoco: Short
Dolicho: long
Hemi: Half
Phoco: Seal-like
Syn: Fused
Term
What environmental effects can cause congenital anomalies of the limbs?
Definition
Hyperthermia
Retinoic Acid
Aspirin
Thalidomide
Term
What are the general categories of anomalies?
Definition
Reduction
Duplication
Dysplasia
Term
What are the General Causes of congenital anomalies of the limbs?
Definition
Arrest in Development
Failure of Differentiation
Duplication
Overgrowth
Hypoplasia
Focal Defects (amniotic band)
General Skeletal abnormalities
Term
What is the anatomical position in developing infants?
Definition
Palm-up, as in the regular anatomical position but the thumb is also pointing up
Term
Hox genes stimulate limb direction in what direction?
Definition
Both Cranial to Caudal as well as Proximal to Distal
Term
What is the organizing center for the proximo-distal growth of limbs?
Definition
Apical Ectodermal Ridge (AER)
Term
What can result from Hox genes being turned off?
Definition
Meromelia
Term
What is the name of the factor that is coordinated by AER for proximal-distal growth of the limb?
Definition
Fibroblst Growth Factor (FGF)
Term
What is the result of blocking AER in early limb development?
Definition
Amelia
Term
What is the organizing center for the anteroposterior growth of limbs?
Definition
Zone of Polarizing Activity (ZPA)
Term
The ZPA works by coordinating the release of what growth factor?
Definition
SHH
Term
In anteriorposterior growth, SHH moves in what direction?
Definition
Caudal to cranial
Term
What transcription factors up regulate SHH, and where are they on the limb?
Definition
Gli-1, caudal
Term
What transcription factors down-regulate SHH, and where are they located?
Definition
Gli-2, Cranially
Term
Too much SHH (either from failure of Gli-2 or over-signalling from Gli-1) can result in what?
Definition
Polydactyly or Polymelia. This is because the overproduction of SHH can lead to a new AER
Term
Too little SSH (from failure of Gli-1 or oversignalling by Gli-2) can result in what?
Definition
Diminished cranial end development. Can result in conditions such a Hemimelia
Term
What protein stimulates apoptosis at the digits?
Definition
BMP: Bone morphogenic protein
Term
Too little BMP results in what condition?
Definition
Syndactyly
Term
Too much BMP results in what condition?
Definition
Polydactyly
Term
Lobster claw is the results of?
Definition
Over-production of BMP
Term
Where do autonomic ganglion come from?
Definition
Neural Crest Cells
Term
Where do somatic nerves of the arms come from?
Definition
Neural Tube (neural ectoderm)
Term
Where does the mesoderm of the limbs come from?
Definition
Lateral Plate
Term
Dorsal muscle of the arm consists of?
Definition
extensors, abductors, and supinators
Term
Ventral limb muscle consists of?
Definition
Flexors, adductors and pronators
Term
What are the last nerve fibers to enter the muscle masses?
Definition
GSA fibers
Supporting users have an ad free experience!