Steve Avery's Reproductive Lockup Flashcards
(287 cards)
Sonic headgehog gene
Produced at the base of the limbs in zone of polarizing activity;
involved in patterning along anterior-posterior axis;
Involved in CNS development;
Mutation can cause holoprosencephaly
Wnt-7 gene
Produced at the apical ectodermal ridge (thickened ectoderm at distal end of each developing limb);
Necessary for proper organization along dorsal-ventral axis
FGF gene
Produced at the apical ectodermal ridge;
stimulates mitosis of underlying mesoderm;
providing for lengthening of limbs
Homeobox (Hox) genes
Involved in segmental organization of embryo in a craniocaudal direction. Hox mutations lead to appendages in wrong locations
Early fetal development: day 0
Fertilization of egg by sperm forming the zygote, initiating embryogenesis
Early fetal development: within 1 week of fertilization
hCF secretion begins around the time of implantation of the blastocyst
Early fetal development: within 2 weeks of fertilization
bilaminar disc (epiblast and hypoblast); 2 weeks= 2 layers
Early fetal development: within 3 weeks of fertilization
trilaminar disc, 3 weeks=3 layers;
gastrulation;
primitive streak, notochord, mesoderm and its organization, and neural plate begin to form
Early fetal development: weeks 3-8 post fertilization
Embryonic period;
neural tube formed by neuroectoderm and closes by week 4;
organogenesis;
extremely susceptible to teratogens
Early fetal development: Week 4
Heart begins to beat;
upper and lower limb buds begin to form;
4 weeks= 4 limbs
Early fetal development: week 6
Fetal cardiac activity visible by transvaginal ultrasound
Early fetal development: week 10
Genitalia have male/female characteristics
Grastrulation
Process that forms the trilaminar embryonic disc;
Establishes the ectoderm, mesoderm, and endoderm germ layes;
starts with the epiblast invaginating to form primitive streak
Surface ectoderm leads to what notable structures
Adenohypophysis (from Rathke pouch); lens of the eye; epithelial lining of the oral cavity, sensory organs of ear, and olfactory epithelium; Epidermis; anal canal below the pectinate line; parotid, sweat, and mammary glands
Craniopharyngioma
Benign Rathke pouch tumor with cholesterol crystals, calcifications
Neuroectoderm leads to what notable structures
Brain (neurohypophysis, CNS neurons, oligodendrocytes, astrocytes, ependymal cells, pineal gland), retina, optic nerve, spinal cord;
Just think CNS
Neural crest leads to what notable structures
PNS (dorsal root ganglia, cranial nerves, celiac ganglion, Schwann cells, ANS); Melanocytes; chromaffin cells of adrenal medulla; Parafollicular C cells of thyroid; pia and arachnoid; bones of the skull; Odontoblasts; aorticopulmonary septum
Mesoderm leads to what structures
Muscle, bone, connective tissue, serous linings of body cavities(e.g. peritoneum), spleen (from foregut mesentery), cardiovascular structures, lymphatics, blood, wall of gut tube, vagina, kidneys, adrenal cortex, dermis, testes, ovaries;
Notochord induces ectoderm to form neuroectoderm (neural plate). Its post natal structures are
Nucleus pulposus of the intervertebral disc. That is it.
Endoderm
Gut tube epithelium (including anal canal above the pectinate line), most of urethra (derived from urogenital sinus), luminal epithelium derivatives (e.g. lungs, liver, gall bladder, pancreas, eustachian tubes, thymus, parathyroid, thyroid follicular cells)
Errors in morphogenesis: agenesis
Absent organ due to absent primordial tissue
Errors in morphogenesis: aplasia
Absent organ despite presence of primordial tissue
Errors in morphogenesis: Hypoplasia
Incomplete organ development;
primordial tissue present
Errors in morphogenesis: Deformation
extrinsic disruption;
occurs after the embryonic period