6 Flashcards
How does the face develop?
Complex process 4-8 weeks in humans
First trimester: Face starts developing.
It starts during neuralation, and neural crest cells migrate to form tissues of the craniofacial region. Neural crest cells (NCC) migrate ventrally from the neural tube to the developing face.
Successive tissue interactions between epithelium and mesenchyme are necessary for facial development, followed by morphogenetic movements.
Medial nasal prominences merge in the midline to create the intermaxillary region.
Upper facial prominences form the jaw. The nose then starts growing, first medially and then laterally. The upper lip is then formed, and nasal placodes become the nasal cavity
What is q-PCR? Advantages and disadvantages of q-PCR
Quantitative polymerase chain reaction. Total RNA was extracted from 6 dissected heads of E9.5 control and mutants (3 and 3). cDNA was synthesized with an RNA polymerase chain reaction kit.
It’s used to amplify and quantify a target DNA molecule.
Did not find significant differences in gene expression
advantages:
Extremely sensitive and specific. Very accurate and allows for quantitative data. It is quite fast. High throughput, real-time monitoring.
Disadvantages:
expensive, complex setup
What is situ hybridization? Advantages and disadvantages
Powerful tool for visualizing gene expression in intact tissues. Visualize location and distribution of DNAA or RNA within intact tissues.
Creates a probe complimentary to the DNA or RNA sequence of interest
Probe then hybridizes to the sequence.
Probe can be visualized using fluorescence microscopy
Advantages:
Allows examination of gene expression within the entire context of an organism’s development. Can be used to understand spatial relationships
NCC identity is determined by? (2)
Based on where they arose
Patterning signals at their arrival
How to develop a cleft lip
Develops at week 6 of embryonic development from the failure of fusion between the lateral, medial nasal and maxillary prominences
