Embryology Flashcards
1
Q
Gene that organizes anteroposterior axis
A
Sonic hedgehog gene
2
Q
Mutation in this gene can cause holoprosencephaly
A
Sonic hedgehog gene
3
Q
Where is sonic hedgehog gene produced?
A
Base of limbs
4
Q
Gene that organizes dorsal-ventral axis
A
WNT-7 gene
5
Q
Thickened ectoderm at distal end of each developing limb
A
Dermal ectodermal ridge
6
Q
Gene that causes mitosis of mesoderm and lengthens limbs
A
FGF gene
7
Q
Where is the FGF gene produced?
A
Apical ectodermal ridge
8
Q
Where is the WNT-7 gene produced?
A
Apical ectodermal ridge
9
Q
Mutation in this gene causes limbs to be in wrong places
A
HOX gene
10
Q
Gene that organizes segmental organization in a craniocaudal direction
A
HOX gene
11
Q
During which week of development does hCG secretion begin?
A
week 1
12
Q
During which week of development does the blastocyst implant?
A
week 1
13
Q
During which week of development does the bilaminar disk form?
A
week 2
14
Q
What tissues make up the bilaminar disk?
A
epiblast and hypoblast
15
Q
Where does the notochord arise from?
A
Midline mesoderm
16
Q
What becomes the neural plate?
A
ectoderm
17
Q
The epiblast invaginates to form what?
A
Primitive streak
18
Q
During which week of development do endoderm, ectoderm, and mesoderm form?
A
Week 3
19
Q
During which week of development does neural tube form?
A
Week 3
20
Q
By which week of development does the neural tube close?
A
week 4
21
Q
During which weeks does organogenesis occur?
A
Weeks 3-8
22
Q
The embryonic period occurs within which weeks?
A
Weeks 3-8
23
Q
Which period of embryo development is most susceptible to teratogens?
A
Embryonic period (weeks 3-8)
24
Q
During which week of development does the heart begin to beat?
A
week 4
25
During which week of development do limbs begin to appear
week 4
26
During which week of development is fetal cardiac activity visible by transvaginal ultrasound?
week 6
27
During which week of development do fetal movements start?
week 8
28
During which week of development do genitalia develop male and female characteristics?
week 10
29
Benign Rathke pouch tumor with cholesterol crystals and calcifications
Craniopharyngioma
30
Adenohypophysis is derived from what tissue?
Rathke pouch (surface ectoderm)
31
Embryonic tissue that gives rise to lens of the eye
surface ectoderm
32
Embryonic tissue that gives rise to epithelial linings of oral cavity
surface ectoderm
33
Embryonic tissue that gives rise to sensory organs of ear and olfactory epithelium
surface ectoderm
34
Embryonic tissue that gives rise to anal canal below the pectinate line
surface ectoderm
35
Embryonic tissue that gives rise to parotid, sweat and mammary glands
surface ectoderm
36
Embryonic tissue that gives rise to CNS structures and cells
Neural tube (Neuroectoderm)
37
Embryonic tissue that gives rise to PNS structures and cells
Neural crest (ectoderm)
38
Embryonic tissue that gives rise to melanocytes
Neural crest (ectoderm)
39
Embryonic tissue that gives rise to chromaffin cells of adrenal medulla
neural crest (ectoderm)
40
Embryonic tissue that gives rise to parafollicular (C) cells of thyroid
neural crest (ectoderm)
41
Embryonic tissue that gives rise to pia and arachnoid
neural crest (ectoderm)
42
Embryonic tissue that gives rise to bones of the skull
neural crest (ectoderm)
43
Embryonic tissue that gives rise to aorticopulmonary septum
neural crest (ectoderm)
44
Embryonic tissue that gives rise to endocardial cushions
neural crest (ectoderm)
45
Embryonic tissue that gives rise to myenteric (Auerbach) plexus
neural crest (ectoderm)
46
Embryonic tissue that gives rise to muscle, bone and connective tissue
mesoderm
47
Embryonic tissue that gives rise to serous linings of body cavities
mesoderm
48
Embryonic tissue that gives rise to the spleen
mesoderm
49
Embryonic tissue that gives rise to cardiovascular structures
mesoderm
50
Embryonic tissue that gives rise to lymphatics and blood
mesoderm
51
Embryonic tissue that gives rise to wall of gut tube
mesoderm
52
Embryonic tissue that gives rise to upper vagina, testes and ovaries
mesoderm
53
Embryonic tissue that gives rise to kidneys and adrenal cortex
mesoderm
54
What induces ectoderm to form neuroectoderm
Notochord
55
What is the postnatal derivative of the notochord
The nucleus pulposus of the intervertebral disk
56
Embryonic tissue that gives rise to gut tube epithelium including anal canal above the pectinate line
endoderm
57
Embryonic tissue that gives rise to most of urethra and lower vagina
endoderm
58
The urogenital sinus gives rise to what part of the vagina?
lower vagina
59
Embryonic tissue that gives rise to lungs, liver, gallbladder, pancreas
endoderm
60
Embryonic tissue that gives rise to thymus, parathyroid, and thyroid follicular cells
endoderm
61
Embryonic tissue that gives rise to the Eustachian tube
endoderm
62
Absent organ due to absent primordial tissue
agenesis
63
Absent organ despite presence of primordial tissue
aplasia
64
Incomplete organ development; primordial tissue present
hypoplasia
65
2ndry breakdown of previously normal tissue or structure
disruption
66
extrinsic disruption after embryonic period
deformation
67
intrinsic reaction during embryonic period
malformation
68
abnormalities resulting from a single primary embryological event (oligohydramnios)
Sequence (Potter sequence from oligohydramnios)
69
Teratogen that causes renal damage
ACE inhibitors
70
Teratogen that causes absence of digits and multiple anomalies
Alkylating agents
71
Teratogen that causes ototoxicity
Aminoglycosides
72
Teratogen that causes neural tube defects, cardiac defects, cleft palate and skeletal abnormalities
Antiepileptic drugs
73
Most common antiepileptic drugs that cause neural tube and cardiac defects, cleft palate and skeletal abnormalities
Valproate, carbamazepine, phenytoin, phenobarbital
74
Teratogen that causes vaginal clear cell adenocarcinoma and congenital Mullerian anomalies
Diethylstilbestrol
75
Folate antagonists that cause neural tube defects
Trimethoprim, methotrexate, antiepileptic drugs
76
Teratogen that causes multiple birth defects and requires mandatory contraception
Isotretinoin
77
Teratogen that causes Ebstein anomaly
Lithium
78
Teratogen that causes aplasia cutis congenita
Methimazole
79
Teratogen that causes discolored teeth and inhibited bone growth
Tetracycline
80
Teratogen that causes limb defects
Thalidomide
81
Teratogen that causes bone deformities, fetal hemorrhage, abortion, and eye abnormalities
Warfarin
82
Teratogen that causes intellectual disability and other birth defects
Alcohol
83
Teratogen that causes low birth weight, preterm birth, IUGR, placental abruption
cocaine
84
Teratogen that causes low birth weight, preterm labor, placental problems, IUGR, SIDS in developing countries
Smoking, nicotine or CO
85
What is the effect of cocaine on blood vessels
Vasoconstriction
86
What is the effect of nicotine on blood vessels
Vasoconstriction
87
Lack of this nutrient will lead to congenital goiter or hypothyroidism (cretinism)
Iodine
88
Condition in mother that can cause caudal regression syndrome, congenital heart defects, neural tube defects, micromsa, and neonatal hypoglycemia
Maternal diabetes
89
Can cause neurotoxicity and found in highest concentrations in swordfish, shark, tilefish, and king mackerel
Mercury
90
High amounts of this vitamin increases risk of spontaneous abortion and birth defects
vitamin A
91
Anal atresia and sirenomalia can be caused by what maternal condition?
Maternal diabetes
92
Needs to be minimized by lead shielding to avoid microcephaly and intellectual ability in developing fetus
X-rays
93
What is the leading cause of intellectual disability in the U.S?
Fetal alcohol syndrome
94
Child presenting with intellectual disability and has smooth philtrum, thin vermillion border and small palpebral fissures is also at risk for what other complications?
Heart and limb defects and holoprosencephaly
95
Holoprosencephaly is caused by what?
Trisomy 13 or alcohol
96
What type of twins are fraternal twins?
Dizygotic
97
What number of chorions and amnions will be present if twinning occurs during 0-4 days?
dichorionic and diamniotic
98
What number of chorions and amnions will be present if twinning occurs during 4-8 days?
monochorionic and diamniotic
99
What number of chorions and amnions will be present if twinning occurs during 8-12 days?
one chorion and amnion
100
What number of chorions and amnions will be present if twinning occurs > 13 days?
one chorion and amnion - maybe conjoined
101
What is the cell stage if twinning occurs in 0-4 days?
2 cell stage
102
What is the cell stage if twinning occurs in 4-8 days?
Morula
103
What is the cell stage if twinning occurs in 8-12 days?
Blastocyst
104
What is the cell stage if twinning occurs in > 13 days?
Formed embryonic disc
105
Which layer of the chorionic villi makes ?
cytotrophoblast
106
which layer of the chorionic villi synthesizes hormones
syncytiotrophoblast
107
Which layer of the chorionic villi is the inner layer ?
cytotrophoblast
108
Which layer of the chorionic villi is the outer layer
syncytiotrophoblast
109
Hormone that is structurally similar to LH and stimulates corpus luteum to secrete progesterone during first trimester
hCG
110
Vessels that return deoxygenated blood from fetus to placenta
Umbilical arteries
111
Supplies oxygenated blood from placenta to fetus
Umbilical vein
112
The umbilical arteries return blood from fetus via what main arteries?
Internal iliac arteries
113
What blood vessel does the umbilical vein drain into?
IVC via ductus venosus
114
What structures are found in the umbilical cord?
2 umbilical arteries
1 umbilical vein
Allantoic duct
Wharton jelly
115
During which week of development is the allantois formed?
week 3
116
To where does the allantois extend?
urogenital sinus
117
What does the allantois become?
Urachus
118
Where is the urachus located?
between the fetal bladder and umbilicus
119
What causes urine to discharge from the umbilicus
Patent urachus - failed to obliterate
120
What is a fluid-filled cavity lined with epithelium between the umbilicus and bladder?
Urachal cyst
121
What is the cause of a urachal cyst?
Partial failure of urachus to obliterate
122
What is a complication of an urachal cyst?
Infection or adenocarcinoma
123
What is an outpouching of the bladder called?
Vesicourachal diverticulum
124
What causes a Vesicourachal diverticulum?
Slight failure of urachus to obliterate
125
During which week of development does the vitelline duct obliterate?
week 7
126
What does the vitelline duct do?
Connects yolk sac to midgut lumen
127
What usually causes meconium discharge from umbilicus?
Vitelline fistula - fails to close
128
Usually presents with melena, hematochezia, and abdominal pain and is attached to ileum
Meckel diverticulum (a true diverticulum)
129
What causes Meckel diverticulum?
Partial closure of vitelline duct
130
Aortic arch that gives rise to part of maxillary artery
1st
131
Aortic arch that gives rise to stapedial and hyoid arteries
2nd
132
Aortic arch that gives rise to common carotid and proximal part of the internal carotid artery
3rd
133
Aortic arch that gives rise to aortic arch and proximal part of right subclavian artery
4th
134
Aortic arch that gives rise to proximal part of pulmonary artery on the left and ductus arteriosus
6th
135
The right recurrent laryngeal nerve loops around which vessel?
Right subclavian artery
136
The left recurrent laryngeal nerve loops around which vessel?
Aortic arch distal to ductus arteriosus
137
Branchial clefts are derived from which embryological tissue?
ectoderm
138
Branchial arches are derived from which embryological tissue?
mesoderm
139
Branchial pouches are derived from which embryological tissue?
endoderm
140
Mnemonic to remember branchial apparatus
CAP covers outside to inside:
C = ectoderm (C=clefts)
A = mesoderm (A=arches)
P = endoderm (P=pouches)
141
What does the first branchial cleft develop into?
external Auditory meatus (A is 1st letter of alphabet)
142
Cyst within lateral neck located anterior to SCM muscle and is immobile during swallowing?
Persistent cervical sinus
143
What causes a persistent cervical sinus?
Failure of 2nd - 4th branchial clefts to obliterate
144
branchial arch that gives rise to CN V2 and V3
1st
145
branchial arch that gives rise to maxillary process, mandibular process, malleus and incus, and sphenomandibular ligament
1st
146
Maxilla and zygoMatic bone are derived from which brachial arch?
1st
147
Meckel cartilage and Mandible are derived from which brachial arch?
1st
148
Malleus and incus are derived from which brachial arch?
1st
149
sphenoMandibular ligament is derived from which brachial arch?
1st
150
Muscles of Mastication are derived from which brachial arch?
1st
151
temporalis Masseter, lateral and Medial pterygoids are derived from which brachial arch?
1st
152
Mylohyoid, anterior belly of digastric, tensor tympani, and anterior 2/3 of tongue are derived from which brachial arch?
1st
153
Stapes, Styloid process, lesser horn of hyoid, Stylohyoid ligament are derived from which brachial arch?
2nd
154
Muscles of facial expression are derived from which brachial arch?
2nd
155
CN VII is derived from which brachial arch?
2nd
156
Stapedius, Stylohyoid, platySma, and posterior belly of the digastric are derived from which brachial arch?
2nd
157
Someone with a small jaw, displaced tongue, cleft palate, and airway obstruction has what sequence?
Pierre Robin sequence
158
Someone with a small jaw, displaced tongue, cleft palate, and airway obstruction has a defect in which brachial arch?
1st
159
Pierre Robin sequence and Treacher Collins syndrome can be caused by defects in which brachial arch?
1st
160
Someone with neural crest dysfunction causing mandibular hypoplasia and facial abnormalities has what syndrome?
Treacher Collins syndrome
161
Someone with neural crest dysfunction causing mandibular hypoplasia and facial abnormalities has a defect in which brachial arch?
1st/2nd
162
Branchial arch that gives rise to Greater horn of hyoid
3rd
163
Branchial arch that gives rise to CN IX (glossopharyngeal nerve)
3rd (3x3=9)
164
Branchial arch that gives rise to stylopharyngeus
3rd
165
Nerve that innervates stylopharyngeus
CN IX (glossopharyngeal nerve)
166
Branchial arch that gives rise to Arytenoids, Cricoid, Corniculate, Cuneiform, Thyroid cartilage (ACCCT)
4th and 6th
167
Branchial arch that gives rise to most pharyngeal constrictors, cricothyroid and levator veli palatini
4th
168
Branchial arch that gives rise to all intrinsic muscles of larynx except cricothyroid
6th
169
Branchial arch that gives rise to superior laryngeal branch of CN X
4th
170
Branchial arch that gives rise to recurrent laryngeal branch of CN X
6th
171
Function of superior laryngeal branch of CN X
Swallow
172
Function of recurrent laryngeal branch of CN X
Speaking
173
What branchial arches contribute to the posterior 1/3 of the tongue?
3rd and 4th
