1.
#1 cause of mental retardation in US, and the leading cause of congenital malformations in the US: Fetal alcohol syndrome
2.
FGF gene: Stimulates mitosis of underlying mesoderm providing for lengthening of limbs
3.
Homeobox (hox) genes: Involved in the segmental organization of embryo in craniocaudal direction
4.
List what happens at each of the fetal landmarks:
Week 1:
Week 2:
Week 3:
Week 3-8:
Week 4:
Week 8:
Week 10:: 1: hCG secretion begins after implantation
2: Bilaminar disk (hypoblast and epiblast
3: Trilaminar disk
3-8: organogenesis; most susceptible to teratogens
4: heart begins to beat and four limbs begin to form
8: movement
10: can recognize genitalia
5.
Name the fetal placental structure that secretes hCG? Name the maternal component of the placenta?: Syncytiotrophoblast
Decidua basalis
6.
Notochord: Develops into the neural plate which gives rise to the neural tube and neural crest. The nucleus propulsa is the remanent of the notochord
7.
Sonic the hedgehog gene: Produced at the base of limbs in the zone of polarizing activity. Involved in patterning along the anterior and posterior axis
8.
What are the stages of the zygote upon fertilization and until implantation?: Zygote - Morulla - Blastocyst (implants around day 6)
9.
What is the embryological origin of the following structures:
1. Anterior pituitary
2. Cornea
3. Lens
4. Retina
5. Olfactory epithelium
6. Mammary glands
7. Salivary glands
8. Sweat glands: 1. Surface ectoderm
2. Neural crest
3. Surface ectoderm
4. Neuroectoderm
5-8. Surface ectoderm
10.
What structures arise from the endoderm: Gut tub epithelium and derivatives: lungs, liver, pancreas, thymus, parathyroid, thyroid follicular cells, eustachian tube, gallbladder
11.
What structures arise from the mesoderm: Muscle, bone, connective tissue, linings of body cavities, spleen, CV structures, lymphatics, blood, bladder, urethra, vagina, kidneys, adrenal cortex, skin dermis, testes, ovaries
12.
What structures arise from the neural crest: PNS, dorsal root ganglia, CN, celiac ganglion, melanocytes, chromaffin cells of the adrenal medulla, parafollicular cells of the thyroid, Schwann cells, pia and arachnoid, bones of the skull, odontoblasts, aorticopulmonary septum, anterior chamber of the eye and its structures
13.
What structures arise from the neuroectoderm: CNS and brain
14.
What structures arise from the surface ectoderm: Adenohypophysis (anterior pituitary), lens of the eye, epithelial lining of the oral cavity, sensory organs of the ear, and the olfactory epithelium, anal canal below the pectinate line, parotid, sweat, and mammary glands
