Home > Flashcards > Print Preview
The flashcards below were created by user
on FreezingBlue Flashcards
. What would you like to do?
Major events: weeks 1 & 2
- Week 1 = implantation (as a blastocyst)
- Week 2 = 2 cell types of embryoblast: epiblast (--> amniotic sac) & hypoblast (--> yolk sac). In other words, it's a bilaminar disk.
Gastrulation (3 germ cell layers), neurulation (form notochord, which induces ectoderm to become neuroectoderm --> neural plate). Also, blood islands form from mesodermal (mesenchymal) cells this week.
Heart begins to beat, limb buds form. Pronephros degenerates after Week 4.
Fetal movement; fetus looks like baby.
External genitals look male or female.
Fate of thyroglossal duct, which connects thyroid to tongue -- the location from which thyroid arises (i.e. floor of pharynx)
- Foramen cecum... or, if not obliterated, then pyramidal lobe of thyroid.
- If parts of duct persist: thyroglossal duct cyst = moves w/swallowing, unlike persistent cervical sinus.
Primary palate = fusion of the...
2 intermaxillary segments, medial nasal prominences.
Secondary palate = fusion of the...
2 palatine shelves (forms the palatine raphe)
Failure of primary palate to fuse (more anterior than secondary palate).
Failure of secondary palate structures to fuse (further posterior).
Name derivatives: 1st through 6th parts of aortic arch
- 1 = maxillary A; 2 = stapedial & hyoid A's
- 3 = common & internal carotid A's
- 4 = (L) aortic arch & (R) subclavian A
- 6 = proximal pulmonary arteries, ductus arteriosus (L)
Name the specific beginning & end points of midgut.
- Begin = duodenum, just past the common bile duct
- End = after first 2/3 of transverse colon
Upper vs. lower anal canals -- formed from:
- Upper = urorectal septum separating the cloaca (end of gut tube)
- Lower = ectoderm
Ventral pancreatic bud
Forms the: pancreatic head, uncinate process (lower 1/2 of head), & main pancreatic duct.
Extrahepatic biliary atresia
Occlusion of bile duct (connects the hepatic diverticulum to foregut) --> pale stool, dark urine, jaundice.
Lungs develop from...
- Endoderm: front wall of foregut.
- Visceral pleura: from mesoderm covering outside of bronchi
- Parietal pleura: from mesoderm of body wall
Forms ureters, collecting ducts, calyces, pelvis
Forms bladder, allantois, urethra.
Bilateral renal agenesis (b/c malformed ureteric bud) --> oligohydramnios, limb & face malformations b/c fetus is pushed up against uterine wall.
Inferior poles of both kidneys fuse. As kidneys ascend upward, they get "stuck" on inferior mesenteric artery & stay low in abdomen... but at least the kidneys function normally.
Connects ovaries to uterus (the place where fallopian tube meets uterus)
Connects ovary to labia majora.
Fate of processus vaginalis in men vs. women
Women = obliterated. Men = becomes tunica vaginalis... if it stays wide open (patent), then congenital inguinal hernia --> intestines can herniate into scrotum or labia majora (less common).
Incomplete fusion of paramesonephric ducts. Infertility, urinary tract abnormalities. It could also be true that 1 of the paramesonephric ducts is rudimentary.
Genital tubercle: male & female homologues
- Male = glans penis, corpus spongiosum
- Female = clitoris, vestibular bulbs
- Bladder, urethra, allantois is true for both genders
- Male = Cowper's glands (bulbourethral), prostate gland
- Female = Bartholin's glands (greater vestibular), urethral & paraurethral glands
Urogenital folds: male vs female
- Female = labia minora
- Male = ventral shaft of penis (underside)
Labioscrotal swelling: male vs. female
- Female = labia majora
- Male = scrotum
Urethra opens on ventral side (underside) of penis; UTI's. More common than epispadias. Failure of urethral folds to close.
Pee shoots up to ceiling: urethra opens onto dorsal side of penis, b/c faulty positioning of genital tubercle (responsible for glans penis).
Sonic hedgehog gene: axis
ZPA --> A-P axis.
Controls dorsal --> ventral patterning: DAER (apical ectodermal ridge).
Surface ectoderm derivatives
Eyes, ears, nose, mouth, skin = epithelial linings. Lens of eye, adenohypophysis. Glands: sweat, saliva, mammary.
Brain, SC, & optic vesicle --> retina, iris, ciliary body. 2 types of neural cells: neuroblasts & glioblasts (for "everything else").
Everything associated with brain & SC. PNS, CN's, dorsal root ganglia, pia & arachnoid mater. Also: chromaffin cells of adrenal medulla, parafollicular (C) cells of thyroid, melanocytes, AP septum.
Epithelium (lining) of gut tube... plus lungs, liver, thymus, parathyroid, pancreas. NOT kidneys.
- Kidneys, urogenital structures, adrenal cortex, cardiovascular/blood/lymphatics, spleen (from foregut mesentery).
- Also: muscle, bone, CT, serious linings of body cavities (ex. peritoneum; sclera, choroid, & anterior chamber for eye).
Auto recess. Abnormally motile cilia (or not at all). Bronchiectasis, female infertility, sinusitis, situs inversus. (If cilia don't move at all, then a 50/50 chance of situs inversus.)
Fetal addiction, developmental defects, placental abruption
Causes clear cell vaginal adenocarcinoma
Iodide (lack or excess)
Hypothyroidism or goiter
Vitamin A (excess)
Spontaneous abortion (just like w/measles), cardiac abnorm's & cleft palate
Placental abnormalities, preterm labor. Also IUGR, ADHD
Inhibit bone growth, discolored teeth
Abortion, fetal hemorrhage, bone deformities
Missing fingers (mnemonic: count the diff types of agents on your fingers)
Fetal alcohol syndrome
- Microcephaly, hydrocephalus, facial abnormalities
- Limb dislocation, heart & lung fistulas
- May be abnormal cell migration.
Monochorionic, diamniotic twins
- The most common setup for identical twins. Separate amniotic sacs, but same chorion & placenta.
- Vs. Siamese twins: 1 amniotic sac, too
What would you like to do?
Home > Flashcards > Print Preview