page 218-237 Flashcards
root formation
Begins at the cervical loop (where the IEE and OEE join) after enamel is first formed.
As the cervical loop elongates, ——– is
formed, which shapes the root(s) and ultimately surrounds the majority of
the ——-. Its most apical segment, the —— ——–, turns
———-, ensuring that the root tapers as odontogenesis proceeds.
As the cervical loop elongates, Hertwig’s epithelial root sheath (HERS) is
formed, which shapes the root(s) and ultimately surrounds the majority of
the dental papilla. Its most apical segment, the epithelial diaphragm, turns
medially, ensuring that the root tapers as odontogenesis proceeds.
(root formation)
As root formation continues, the tooth erupts, leaving the ——- ——–
always at the same location. This eventually forms the —– foramen.
As root formation continues, the tooth erupts, leaving the epithelial diaphragm
always at the same location. This eventually forms the apical foramen.
As ——- dentin is formed, —– begins to disintegrate, leaving behindpatches of epithelial cells called —– ——- ——-
As radicular dentin is formed, HERS begins to disintegrate, leaving behindpatches of epithelial cells called epithelial rests of Malassez.
The collapse of HERS enables ectomesenchymal cells of the dental follicle to contact dentin and differentiate into the formative cells of the periodontium:
x
y
z
cementoblasts (forming cementum), osteoblasts (forming alveolar bone proper), and fibroblasts (forming the PDL).
tooth eruption
As the tooth erupts into the oral cavity, the —- fuses with the —– ——–,
forming the ——– junction (epithelial attachment).
As the tooth erupts into the oral cavity, the REE fuses with the oral epithelium,
forming the dentogingival junction (epithelial attachment).
—– —- later migrates apically along the tooth to its normal position in which
the most apical cells of the JE are at the —-.
A delay in this apical migration
is known as delayed (altered) —— eruption.
dentogingival junction (epithelial attachment). later migrates apically along the tooth to its normal position in which
the most apical cells of the JE are at the CEJ. A delay in this apical migration
is known as delayed (altered) passive eruption.
fertilization
Capacitation and acrosomal reaction of sperm.
entry of spermatozoa
Inhibition of polyspermy.
Acrosome reaction: Sperm releases enzymes to penetrate outer surface
of egg.
Cortical (zona) reaction: Sperm alters zona pellucida, preventing
other sperm from binding.
Meiosis II occurs in oocyte.
Barr body (second polar body).
Fusion of male and female pronuclei.
zygote
restoring diploids
BILAMINAR DISC
■ Occurs in the —- week.
■ Epiblast (primary ectoderm).
■ Amniotic cavity.
■ Ultimately gives rise to:
BILAMINAR DISC
■ Occurs in the second week.
■ Epiblast (primary ectoderm).
■ Amniotic cavity.
■ Ultimately gives rise to:
■ Ectoderm.
■ Mesoderm.
FETAL CIRCULATION
See Figure 4–12.
Oxygenated blood to heart via
Umbilical vein.
Inferior vena cava.
Foramen ovale
■ Allows most of the oxygenated blood to bypass the pulmonary circuit.
■ Pumps out the aorta to the head.
Deoxygenated blood returned via
■ Superior vena cava.■
■ Superior vena cava.
deoxy blood
Mostly pumped through the pulmonary artery and ductus arteriosus to the:
■ Feet.
■ Umbilical arteries.
ectoderm of skin
endorm
mesoderm
Forebrain 1st and 2nd subsets
1; Prosencephalon
2; Telencephalon diencephalon
Cerebrum, basal
ganglia
telencephalon
diencephalon
Thalamus
Hypothalamus
Epithalamus
Subthalamus
Posterior pituitary
(neurohypophysis)
midbrain
midbrain
mesencephalon
pons
metaencephalon of hindbrain
med. obl.
myencephalon of hindbrain
Neuroblasts → neurons
Ependymal cells (lining ventricles, central canal)
Glioblasts-astrocytes, oligodenrocytes (myelin in CNS)
neuroep.
microglia
mesenchymal derivative
neural crest
Sensory ganglia (CNs V, VII, IX, X)
Dorsal root ganglia (in peripheral nervous system)
Schwann cells (peripheral)
Melanocytes and odontoblasts
Enterochromaffin cells
Neurons in parasympathetic and sympathetic
ganglia (adrenal medulla)
Leptomeninges (pia and arachnoid)
Parafollicular cells (C-cells) of parathyroid
from neural crest
Aortic arch arteries
■
Form during week 4.
Arise from distal truncus arteriosus (aortic sac).
■ Associated with corresponding pharyngeal arch.
aortic arch art
Connect to the paired dorsal aortae.
■ Dorsal aortae fuse in week 5 to form:
Descending thoracic aorta.
Abdominal aorta.
aortic arch art.
Maxillary artery
aortic arch 1
Hyoid artery
Stapedial artery
aortic arch 2
aortic arch 3
Common carotid artery
ICA (first part)
aortic arch and r. subclavia
arotci arch 4
involutes
aortic arch 5
Pulmonary arteries (proximal)
Ductus arteriosus
aortic arch 6
Celiac trunk
Foregut
Vagus nerve
(parasympathetic)
Splanchnic nerve (sympathetic)
Thoracic nerve
Pancreas
4gut
4gut
Esophagus
Duodenum (1st part)
sotmach
Liver
Gallbladder
Pancreas
SMA
midgut
Vagus nerve
(parasympathetic) parts)
Splanchnic nerve (sympathetic)
midgut
DJI
Appendix
Ascending and
transverse colon
midgut
IMA
hindugt
Pelvic splanchnic S2–S4) nerve– (parasympathetic)
Lumbar splanchnic nerve (sympathetic)
hindgut
sigmoid
rectum
colon(distal to splenic flexure)
hindgut
https://drive.google.com/open?id=0B8uJUY-tie8Gc0pEelJSU2xpa00
https://drive.google.com/open?id=0B8uJUY-tie8GUVFDUWJFN0FqdWs
https://drive.google.com/open?id=0B8uJUY-tie8GSDk0dzV6QkVVbUk
https://drive.google.com/open?id=0B8uJUY-tie8GOXZWRl9QU1RfRVU
https://drive.google.com/open?id=0B8uJUY-tie8GcFlTN0pQb210dE0
https://drive.google.com/open?id=0B8uJUY-tie8GZF8zRWJ2V0lHQkE
From intermediate mesoderm
■ Nephrogenic cord gives rise to:
■ Pronephros.
■ Mesonephros.
■ Metanephros.
https://drive.google.com/open?id=0B8uJUY-tie8GNC1QUWdkTWdGams
https://drive.google.com/open?id=0B8uJUY-tie8GSk12Vlp6bFBvSHc
https://drive.google.com/open?id=0B8uJUY-tie8GX195bmdtM0lxeVU
https://drive.google.com/open?id=0B8uJUY-tie8GQVlURXdqR19SQjg
https://drive.google.com/open?id=0B8uJUY-tie8GeTRNWXRUODNvbjQ
https://drive.google.com/open?id=0B8uJUY-tie8GeTRNWXRUODNvbjQ
https://drive.google.com/open?id=0B8uJUY-tie8GU2NNU0JVVXFudnM
https://drive.google.com/open?id=0B8uJUY-tie8GQkZqaERNWWFJZ2M
https://drive.google.com/open?id=0B8uJUY-tie8GdzE2OFFGNmxwdkU
https://drive.google.com/open?id=0B8uJUY-tie8GR05oWS1KRUp3dTA
br. arch
Rounded, mesodermal ridges (neural crest cells).
■ Form from proliferative activity of neural crest cells.
Nerves (CNs V, VII, IX, X) are
branchiomeric because they originate
from the branchial arches.
■ Not from somites.
■ Develop about week 4 of life.
br. arch
At the end of week 4 the arches are well-defined and visible externally.
br. arch
During week 4 the first branchial arch divides into:
■ Mandibular process.
■ Maxillary process.
■ Weeks 5–6, arches are smaller, not seen on surface.
■ Arches 1–3 play role in forming face and oral cavity.
br. arch 1
Arch 1
■ Mandible
■ Maxilla (most)
br. arch 2 and 3
tongue
https://drive.google.com/open?id=0B8uJUY-tie8GV0JXTUdLQjVaZE0
https://drive.google.com/open?id=0B8uJUY-tie8GTTFQckcxUnlCMEU
https://drive.google.com/open?id=0B8uJUY-tie8GNlhvQjVkU1NSRVk
https://drive.google.com/open?id=0B8uJUY-tie8GdG9lTHJCR3d2VnM
https://drive.google.com/open?id=0B8uJUY-tie8Gdl9aT3NlT2pJV0U
https://drive.google.com/open?id=0B8uJUY-tie8GVE5oelRfS1FZOEU
