Embryology Flashcards
(214 cards)
1
Q
- The principal energy source for ejaculation spermatozoa is:
a. prostatic acid phosphatase
b. internal glucose
c. prostatic citric acid
d. fructose in seminal vesicle fluid
e. glycogen release from the vaginal epithelium
A
d. fructose in seminal vesicle fluid
2
Q
- Of the barriers to sperm survival and transport within the female reproductive tract, low pH is most important in the:
a. upper uterine tube
b. lower uterine tube
c. uterine cavity
d. cervix (is a barrier for other reasons not pH)
e. vagina
A
e. vagina
3
Q
- During the menstrual cycle, a sharp spike in plasma levels of which of the following hormone jus before ovulation is responsible for ovulation?
a. fsh
b. LH
c. estrogen
d. progesterone
e. estradiol 17 beta
A
b. LH
4
Q
- Transcription of which of the following genes is required to permit cleavage to proceed to the 2 cell stage in mammalian embryos?
a. nanog
b. 4-oct
c. cdx-2
d. sox-2
A
b. 4-oct
5
Q
- Which of the following cells are responsible for the production of testosterone in the testes?
a. sertoli cells
b. leydig cell
c. grandulose cells
d. spermatogonia
A
b. leydig cell
6
Q
- The graafian follicle, in addition to participating in ovulation, also has endocrine function. What components of the graafin cfollicle formteh corpus luteum?
a. granulose cells
b. Thecal cells
c. Corona radiate cells
d. Both granulose and thecal cells
A
d. Both granulose and thecal cells
7
Q
- In mammalian embryos, unlike non mammalian and inverte embryos, most transcription via the embryonic genome, as opposed to the maternal genome, occurs as early as which ofhe following stages
a. zygote
b. 4-cell stage
c. balstula
d. gastula
A
b. 4-cell stage
8
Q
- In Drosophoila from which ofhte following genes categories adre mRNA derived fromt eh maternal genone rathe than embryonic genome
a. Egg polarity genes
b. Pair rule genes
c. Homeotic genes
d. Gap genes
A
a. Egg polarity genes
9
Q
- Which of the following is a transcription factor
a. FGF
b. Pax
c. TGF
d. Notch
e. Wnt
A
b. Pax
10
Q
- Zinc fingers or helix loop helix arrangements are characteristic of members of what class of molecules?
a. Proto-oncogenes
b. Signaling molecules
c. Receptors
d. Transcription factors
e. None of the above
A
d. Transcription factors
11
Q
**12. Sonic hedgehog is produced in which signaling center
a. Notochord
b. Interstinal portals
c. Floor plate of neural tube
d. Zone of polarizing activity in the limb bud
e. All of the above
A
e. All of the above
12
Q
- Based on your knowledge of paralogous groups, which gene would be expressed most anteriorly in the embryo?
a. Hoxa-13
b. Hoxc-9
c. Hoxd-13
d. Hoxb-1
e. Hoxb-6
A
d. Hoxb-1
13
Q
**14. The principal inductor in primary neural induction is the:
a. Hypoblast
b. Primitive streak
c. Extraembryonic mesoderm
d. Notochordal process
e. Embryonic ectoderm
A
d. Notochordal process
14
Q
- Cells of which germ layer are not present in the oropharyngeal membrane?
a. Ectoderm
b. Mesoderm
c. Endoderm
d. All are present
A
b. Mesoderm
15
Q
- Brachyury, a deficiency in caudal tissues in the body, is cuased by a mutation in what gene?
a. Lim-1
b. Noggin
c. T
d. Sonic hedgehog
e. Activin
A
c. T
16
Q
**Hypoblast is a bilaminar, early embryo gives rise to which of the following tissue types?
a. Extraembryonic only
b. Embryonic only
c. Embryonic and extraembryonic
d. Neither
A
a. Extraembryonic only
17
Q
- In meiosis pair of homologous chromosomes begins during which of the followoing stages of prophase I: a. Leptotine b. Zygotene c. Pachytene d. Diplotene
A
b. Zygotene
18
Q
- Which of the following description best describes the oogonium and the ovary during the early fetal period? a. Diploid, no follicle b. Diploid, few follicle cells c. Haploid, no follicle d. Haploid, few follicle cells
A
a. Diploid, no follicle
19
Q
- Inhibin released by the granulose cells during the mammary cycle inhibits secretions of gonadotropins especially FSH. Resulting in which of the following
A
Regression of the corpus luteum
20
Q
- Splitting of the blastocyst during early development, results in the two complete blastocyst enclose within a single trophoblast is the most common mode of twinning. Assuming complete normal identical twins result what developmental property is illustrated? a. Differentiation b. Determination c. Regulation d. Morphogenesis
A
c. Regulation
21
Q
A 33 year old woman has have both ovaries removed because of large bilateral ovarian cyst. The next year she is on an extended expedition in northern canada, and her canoe tips, sending her replacement hormonal medicate to the bottom of the lake. More than 6 weeks elapse before she is able to obtain a new supply of medication. Which of the following would be least affected by the loss of the medication? A. blood levels of FSH and LH B. Ciliated cells of the uterine tube C. Mass of the heart D. Glandular tissue of the breasts E. Thickness of the endometirum
A
C. Mass of the heart
22
Q
During spermatogenesis, histone is replaced by which of the following, to allow better packing of the condensed chromatin in the head of the spermatozoon? A. inhibin b. prostaglandin E c. testosterone d. protamine e. androgen-binding protein
A
d. protamine
23
Q
Which cell type is located outside the blood-testis barrier? A. spermatozoon B. Secondary spermatocyte C. Spermatid D. Primary spermatocyte E. Spermatogonium
A
E. Spermatogonium
24
Q
Which of the following cells normally participates in mitotic divisions? A. primary oocyte B. oogonium C. Primary spermatocyte D. spermatid E. secondary spermatocyte
A
B. oogonium
25
\*\* At what stage of oogenesis is meiosis arrested in the female?
Metaphase I
Anaphase I
Prophase I
Metaphase II
Telophase I
At prophase (dipotene stage) of the first meiotic division and at metaphase of second meiotic division
26
What is the underlain cause of most spontaneous abortions during the early weeks of pregnancy?
Chromosomal abnormalities such as polyploidy
27
\*\*The actions of what hormones are responsible for the changes in the endometrium during the menstrual cycle
Estrogen, secreted by ovary support preovulatory proliferative phase Progesterone is secreted by corpus luteum
28
Sertoli cells in the testis are stimulated by what two major reproductive hormones?
FSH produced by anterior pituitary Testosterone produced by Leydig cells
29
What is the principle hormonal stimulus for ovulation?
The sharp surge of LH
30
What is capacitation?
Interaction between a spermatozoon and female reproductive tissues that increase sperm ability to fertilize an egg
31
Where does fertilization occur?
upper this of uterine tube
32
What is polyspermy, how is it prevented after a spermatozoon enters the egg
prevented through fast block
33
What is the most common condition associated with spontaneous aborted embryos? A. Maternal imprinting B. Paternal imprinting C. Ectopic pregnancy D. Chromosomal abnormailites E. Lack of X-chromosomal inactivation
D. Chromosomal abnormailites
34
What tissue from the implanting embryo directly interfaces with the endometrial connective tissue A. Corona radiata B. Inner cell mass C. Extraembryonic mesoderm D. Epiblast E. Syncytiotrophoblast
E. Syncytiotrophoblast
35
The zona pellucida: A. Aids in the penetration of the endometrail epithelium B. Serves as a source of nutrients for the embryo C. Prevents premature implantation of the cleaving embryo D. All of the above E. None
C. Prevents premature implantation of the cleaving embryo
36
What is the importance of the inner cell mass of the cleaving embryo?
The embryonic body proper arises from the inner cell mass
37
Parental imprinting is a phenomenon showing that certain homologous maternal and paternal chromosomes have different influences on the development of the embryo. Excess paternal influences result in abnormal development of what type of tissue at the expense of development of the embryo itself?
Trophoblastic issues
38
What is the function of integrins in implantation?
They allow the trophoblast of the embryo to adhere to the uterine epitheium
39
Where in the cell is the retinoid acid receptor located?
The receptors for retinoid acid are located in nucleus
40
A mutation for what receptor is the basis for basal carcinomas of the skin? A. Patched B. Retinoic acid C. Notch D. FGF receptor E. None
A. Patched
41
Zinc finger or helix loop helix arrangements are characteristic of members of what class of molecules? A. proto-oncogenes B. signaling molecules C. Receptors D. Transcription factors E. None
D. Transcription factors
42
A 35 year old married man with a history of chronic respiratory infection sis found on a routine X-ray examination to have dextrocardia. Further physical examination and imaging studies reveal that he has complete sinus inversus. He has also been going to another clinic for completely different problem, which is related to the same underlying defects. What clinic a. urology b. dermatology c. infertility d. orthopedic e. oncology
c. infertility Because of respitatory issues with situs inverses, probably has mutation of a dynein gene. Person have immotile sperm
43
Which of the following tissues arises from cells passing through the primitive streaks? a. embryonic endoderm b. hypoblast c. cytotrophoblast d. primary yolk sac e. anmion
b. hypoblast
44
The prechordal plate plays an important role in regionalization of the: a. notochord b. forebrain c. embryonic mesoderm d. primitive node e. hindbrain
b. forebrain
45
Which layer of the bilaminar (two-layered) embryo gives rise to all of the embryonic tissue proper?
Epibalst
46
Of what importance is the primitive node in embryonic development?
acts as organizer
47
The migration of mesodermal cells from the primitive streak is facilitated by the presence of what molecules of the extracellular matrix?
hyaluronic acid and fibronectin
48
What molecules can bring about mesodermal induction in an early embryo
Vg1 and activin
49
At what stage in the life history of many cells are cell adhesion molecules lost?
migratory phase Re-express when settle down
50
Which of these cell and tissue types arises from cranial, but not trunk, neural crest cells? A. Sensory ganglia B. Adrenal medulla C. Melanocytes D. Schwann cells E. None of the above
E. None of the above
51
Which of the following is a poor substrate for migrating neural crest cells? A. Laminin B. Chondroitin sulfate C. Fibronectin D. Type IV collagen E. Hyaluronic acid
B. Chondroitin sulfate
52
Neural crest cells arise from which of the following? A. Somite B. Dorsal non-neural ectoderm C. Neural tube D. Splanchnic mesoderm E. Yolk sac endoderm
C. Neural tube
53
Which of the following is involved in the migration of neural crest cells from the neural tube? A. Snail B. BMP-2 C. Mash-1 D. Norepinephrine E. Glial growth factor
A. Snail (Slug)
54
Which is not a derivative of neural crest? A. Sensory neurons B. Motor neurons C. Schwann cells D. Adrenal medulla E. Dental papilla
B. Motor neurons
55
What maintains the competence of neural cells to differentiate into autonomic neurons? A. Shh B. Acetylcholine C. Mash 1 D. Glial growth factor E. TGF-Beta
C. Mash 1
56
If trunk neural crest cells are transplanted into the cranial region, they can form all of the following types of cells except: A. Pigment cells B. Schwann cells C. Sensory neurons D. Cartilage E. Autonomic neurons
D. Cartilage
57
\*\*What molecule produced by the notochord is instrumental in inducing the floor plate of neural plate?
A. Hoxa-5
B. Retinoic acid
C. Pax-3
D. Msx-1
E. Shh
E. Shh
58
The cell bodies of the motor neurons of a spinal nerve arise from which of the following? A. Basal plate B. Marginal zone C. Floor plate D. Roof plate E. Alar plate
A. Basal plate
59
Growth cones adhere strongly to a substrate containing which of the following? A. Acetylcholine B. Laminin C. Epinephrine D. Norepinephrine E. Shh
B. Laminin
60
Complete failure of the neural tube to close in the region of the spinal cord is: A. Spina bifida occulata B. Meningocele C. Cranioschisis D. Rachischisis E. Myelomeningocele
D. Rachischisis
61
Rhombomeres are segmental divisions of which of the following? A. Forebrain B. Midbrain C. Hindbrain D. Spinal cord E. None of the above
C. Hindbrain
62
Rathke’s pouch arises from which of the following? A. Diencephalon B. Stomodeal ectoderm C. Mesencephalon D. Pharyngeal endoderm E. Infundibulum
B. Stomodeal ectoderm
63
Shaping of the snout involves the establishment of a gradient between which of the following pairs of signals? A. FGF-8 and Edn-1 B. Hox and Pax C. TGF-2 an dBMP-4 D. FGF-8 and Shh
D. FGF-8 and Shh
64
\*\*In craniofacial development, segmentation of the cranial neural tube occurs as a result of expression of which of the following genes?
A. Sox
B. BMP
C. Hox
D. TGF
C. Hox
65
Except for the pharyngeal muscles, pharyngeal arch mesoderm (tendons, etc.) are derived from which of the following? A. Neural crest B. Somitomeres C. Paraxial mesoderm D. Parachordal mesoderm
A. Neural crest
66
In molar development, induction of secondary enamel knots by the primary enamel knot followed by apoptosis of the primary enamel knot is associated with which of the following morphogenic events? A. Formation of future molar cusps B. Induction of the ameloblast layer C. Induction of ondontoblast layer D. Formation of the dental sac
A. Formation of future molar cusps
67
At which of the following stages in tooth development do both the ameloblast and odontoblast layers first appear together? A. Tooth bud stage B. Cap stage C. Bell stage D. Dental sac stage
C. Bell stage
68
Which of the following is necessary for tooth development to continue past the bud stage? A. BMP-4 B. Shh C. FGF-8 D. Pax-9
D. Pax-9
69
Cleft lip results from lack of fusion of which of the following? A. Nasomedial and nasolateral process B. Nasomedial and maxillary processes C. Nasolateral and maxillary D. Nasolateral and mandibular processes
B. Nasomedial and maxillary processes
70
Which of the following abnormalities in teath development is characterized by teeth the appear blue-gray or amber brown and are opalescent and may be caused by mutation in type I collagen? A. Amelogenesis imperfecta B. Dentinogenesis imperfecta C. Enamel fluorosis D. KGB syndrome
B. Dentinogenesis imperfecta
71
Muscles of facial expression are innervated by cranial nerve seven. This relationship would suggest that these muscles are derived form which of the following pharyngeal arches? A. First B. Second C. Third D. Fourth
B. Second
72
The malleus of the middle ear in mammals is derived from which of the following former jaw articulation bones? A. Columella B. Meckel’s cartilage C. Quadrate D. Articular
Articular
73
Which bone forms around Meckel’s cartilage? A. Mandible B. Malleus C. Stapes D. Maxilla
A. Mandible
74
Which of the following develop from the third pharyngeal pouch in response to high concentrations of Shh? A. Thyroid B. Superior parathyroids C. Thymus D. Inferior parathyroids
D. Inferior parathyroids
75
Hypoplasia of mandible and facial bones is commonly associated with an autosomal dominant condition involving TCOF1 gene. IN this condition, there is reduced populationof neural crest cells in 1st pharyngeal arch. This condition is associated with which of the following anomalies? A. Treacher Collins Syndrome B. Pierre Robin Syndrom C. DiGeorge syndrome
A. Treacher Collins Syndrome
76
Which of the following is derived from Rathke’s pouch? A. Neurohypophysis B. Thymus C. Adenohypophysis D. Thyroid
C. Adenohypophysis
77
The auditory tube is derived of which of the following pharyngeal pouches? A. First B. Second C. Third D. Fourth
First
78
Calcitonin secreting cells (C cells\_, embedded in the thyroid gland, are derived from which of the following primordia? A. Ventral midline gut endoderm B. Third pharyngeal pouch C. Fourth pharyngeal pouch D. Rathke’s pouch
C. Fourth pharyngeal pouch
79
An infant with a tuft of hair over the lumbar region of the vertebral column undergoes surgery for a congenital anomaly in that region. During surgery it was found that the dura and arachnoid layers over the spinal cord were complete, but that the neural arches of several vertebra were missing. What condition did the infant have? Meningocele Meningomyelocele Encephalocele Spina bifida occulta rachischisis
Spina bifida occulta
80
6 month- old infant exhibits multiple congenital defects, including cleft palate, deafness, ocular hypertelorism, and a white forelock but otherwise but otherwise dark hair on his head. The probable diagnosis is CHARGE association Von Recklinghausen's disease (fibroneuromas) Hirchsprung's disease Waardenburg's syndrome None of the above
Waardenburg's syndrome
81
Neural-crest derived cells constitute a significant component of which tissue of the eye Neural retina Lens Optic nerve Cornea None
Cornea
82
The otic placode arises through an inductive message given off by the Telencephalon Rhombencephalon Infundibulum Diencephalon Mesencephalon
Rhombencephalon
83
What molecule plays a role in guidance of advancing retinal axons through the optic nerve Pax2 FGF3 BMP4 PAX6 BMP7
Pax2
84
Surface ectoderm is induced to become corneal epithelium by an inductive event originating in the Optic cup Chordamesoderm Optic vesicle Lens vesicle Neural retina
Lens vesicle
85
The second pharyngeal arch contributes to the Cochlea and earlobe Auditory tube and incus Stapes and earlobe Auditory tube and stapes Otic vesicle and stapes
Stapes and earlobe
86
The facial nerve (CN 7) supplies muscles derived from which pharyngeal arch? First Second Third Fourth Sixth
Second
87
In the case of holoprosencephaly, defects of facial structures are typically secondary to defects of the Pharynx Oral cavity Forebrain Eyes Hindbrain
Forebrain
88
Meckel's cartilage is a prominent structure in the early formation of the Upper jaw Hard palate Nasal septum Soft palate Lower jaw
Lower jaw
89
An early induction in tooth development consists of the ectoderm of the dental epithelium acting on the underlying neural crest mesenchyme. Which of the following molecules is an important mediator of the inductive stimulus? BMP-4 Tenascin Hoxb-13 Msx-1 Syndecan
BMP-4
90
Which of following does not connect directly with the primary nephric (mesonephric) duct? Metanephros Cloaca Nephrotomes Mesonephric tubules Ureteric bud
Metanephros
91
Which association is correct? Potter's facies and hydramnios Urachal fistula and hydramnios Horseshoe kidney and superior mesneteric artery GDNF and metanephrogenic blastema Bilateral renal agenesis and compensatory hypertrophy
GDNF and metanephrogenic blastema
92
Which defect is strongly associated with olifohydramnios? Pelvic kideny Renal agenesis Horseshoe kidney Crossed ectopia Polycystic kidney
Renal agenesis
93
The uterus arises from? Paramesonephric ducts Urogenital sinus Mesonephric tubules Pronephric ducts Mesonephric ducts
Paramesonephric ducts
94
The metanephrogenic blastema is induced by the Pronephric duct Ureteric bud Mesonephric tubules Allantois Mesonephric duct
Ureteric bud
95
Nucleated erythrocytes found circulating in the embryo are produced in the Yolk sac Para-aortic clusters Liver Bone marrow None of above
Yolk sac
96
In a 7M fetus, blood draining the left temporalis muscle enters the heart via the Left anterior cardinal vein Coronary sinus Left common cardinal vein Superior vena cava None of above
Superior vena cava
97
Adherons are inductive particles released by what structure in the endocardinal cushion area? Endocardium Cardiac jelly Myocardium Epicardium None of above
Myocardium
98
Neural crest contributes to the structures of which of the following Truncus arteriosus Ascending aorta Plumonary trunk All of the above None of the above
All of the above
99
For which of these cardiovascular malformations is a paten ductus arteriosus necessary for survival of the individual Atrial septal defect Ventricular septal defect Double aortic arch Right subclavian artery from arch of aorta None of the above
None of the above
100
5 days after birth, an infant becomes cyanotic during a prolonged crying spell. Cyanosis is most likely caused by venous blood entering the systemic circulation through the Interatrial septum Ductus arteriosus Ductus venosus Umbilical vein Interventricular septum
Interatrial septum
101
The internal carotid artery arises from aortic arch number 1 2 3 4 5
3
102
10. Infant w/ Tuft of hair, dura and arachnoid layers complete, neural arches of several vertebrae missing? Which of the following did it have? a. Meningocele b. Meningomyelocele c. Encephalocele d. Spina bifida occulta e. Rachischisis
d. Spina bifida occulta
103
18. Which of the following is caused by failure of the choroid fissure to close during the sixth week of pregnancy? a. Anophthalmos b. Microphthalamos c. Cyclopia d. Colobomo e. Presbyopia
Colobomo
104
Neural crest cells form many components of the nervous system but do not form what?
Motor neurons
105
What mutant has specific behavioral defects related to the cerebellum? Due to what abnormal cell? Formation of what abnormal
Weaver Radial glial cells in cerebellum Formation of granular layer of the cerebellar cortex
106
What is characterized by abnormal behavior and absence of normal cortical layering? What is defective? What does this do?
Reeler Reelin: extracellular protein defective Reelin: may serve as a stop signal for radial neuronal migration or as an insertional signal for migrating neurons
107
Rostral patterning center?
FGF-8
108
What may serve as a stop signal for radial neuronal migration or as an insertional signal for migrating neurons
Reelin
109
Dorsal patterning center?
BMPs and Wnts
110
Ventral patterning center
Shh
111
Neural crest cells are from what?
Neural plate
112
Neural crest cells from trunk transplanted into head form most neural crest derivates except -What also differentiates
Cartilage or skeletal elements (even though normally do) Some cells differentiate into cholinergic parasym instead of adrenal sympathetic normally produced
113
Most neural crest cells from somites 1-3
Pass into pharyngeal arches 4 and 6 or form cardiac crest
114
Neural crest cells from somites R4-R7
Make up vagal crest Form parasympathetic innervation for digestive tract
115
What induces formation of lens placed from lens ectoderm?
Optic vesicle
116
Absence of Pax6 in eye development
Optic vesicle can't induce formation of lens placode
117
Corneal epithelium is induced to from cornea by what?
Lens vesicle
118
groove in optic vesicle is what?
Choroid fissure
119
What runs in the choroid fissure?
Hyaloid artery to posterior chamber
120
Rathke's pouch is an evagination from the roof of what? What is its primordium for the anterior pituitary
Stomodeal ectoderm -Adenohypophysis
121
First arch develops into ______ because of the lack of _____ gene expression
Jaws Hox
122
Expression of what keeps arch 2 from differentiating into arch 1 and forming jaws
Hoxa2
123
What is necessary for tooth development to continue past the bud stage
Pax9
124
Primary enamel knots can give rise to secondary enamel knots which progress to what
Molar cusps
125
For salivary gland development the signaling between Shh and FGF occurs where
Within the epithelium (Rather then between epithelium and mesenchyme)
126
Malformation of anterior endoderm and prechordial plate leads to this clinical
Holoprosencephaly
127
Main organizer for pharyngeal arch development is
Foregut endoderm
128
The opening of the thyroglossal duct that persists as a small pit at base of tongue
Foramen cecum
129
Prevents neurons from crossing the midline of the central nervous system
Slit-2 and Robo
130
Uroplakins
Proteins that make the ureter epithelium impermeable to water
131
Steps in potters syndrome
1. Renal agenesis --\> 2. Reduced urinary output --\> 3. Oligohydramnios--\> 4a. Hip dislocation 4b. pulmonary hypoplasia --\> death 4c. flattened face and ears
132
If SRY gene then get what factor
Sox-9
133
What maintains meiotic competency of germ cells and without individuals would be sterile
Dazl
134
Primary heart field -Name -Part of heart -Exposure -Timeline -Express
Heart crescent Left ventricle and atria -atria if high RA -ventral if not RA Most primitive Express Hand-1
135
Secondary heart field -Part of heart -Derived -Form -Express
Right ventricle and proximal outflow tract Derived from pharyngeal mesoderm Can form cardiac or skeletal muscle Express Hand-2
136
Primary myocardium is guided by
Tbx-2
137
What is the first asymmetrical embryonic structure to appear
Cardiac tube
138
Chamber myocardium is guided by
Tbx-5
139
Interatrial septum primum
Downward growth from cephalic wall of single atrium to endocardial cushion Separates atrium into left and right chambers
140
Interatrial septum secundum
Forms to the right of septum primumand grows from dorsal to the ventral part of atrium
141
Foramen ovale -what is it -where
Right to left atrial shunt Space formed within the septum secundum
142
Fourth aortic arch -Right -Left Sixth aortic arch -associated with -dorsal portion
Right- Right subclavian A Left- Aortic arch Pulmonary system Dorsal portion becomes ductus arterioles shunt --\> ligamentum arteriosus
143
Right vitelline vein becomes
Portal vein
144
Left umbilical vein becomes
Hepatic portal vein
145
What allows oxygenated placental blood to bypass capillary network of liver
Ductus venosus
146
\*\*In the mature placenta, which fetal tissue directly interfaces with the maternal uterine connective tissue?
A. Cytotrophoblast
B. Syncytiotrophoblast
C. Extraembryonic mesoderm
D. Decidual cells
E. None of the above
Cytotrophoblast
147
Which structure is mesodermal in origin?
A. Hair shaft (ectodermal)
B. Mammary duct
C. Sebaceous gland
D. Arrector pili muscle
E. None of the above
Arrector pili muscle
148
In the let-down of milk during lactation, the myoepithelial cells contract in response to:
A. Progesterone
B. Oxytocin
C. Estrogens
D. Oxycontin
E. Lactalbumin
Oxytocin
149
\*\*Which of the following results occurs when all the Hox10 paralogs are knocked out?
A. The sacrum fails to form
B. The tip of the xiphoid process is split
C. Ribs form on the lumbar and sacral vertebrae
D. Hypoplasia of the clavicle and delayed ossification of the skull
Ribs forms on teh lumbar adn sacral vertebrae
150
Which of the following signaling molecules is involved in the epidermal induction that results in the mesenchymal aggregation that forms the dermal papilla?
A. Dermo-1
B. Wnt-11
C. Shh
D. Noggin
Shh
151
Inductive influence of which of the following signal molecules results in the formation of individual mammary placodes?
A. Dermo-1
B. Neurogulin-3
C. Shh
D. Tbx-3
Neurogulin-3
152
Which of the following factors functions as the initial initiator of future forelimb development?
A. Hoxd
B. Tbx5
C. Shh
D. Gli3
Tbx5
153
The most serious threat in fetal hydrops is CNS damage. The affected brain is enlarged and edematous and, when sectioned, has abright yellow color, particularly the basal nuclei, thalamus, cerebellum, cerebral gray matter, and spinal cord. The CNS damage is known as which of the following?
A. Erythroblastosis fetalis
B. Kernicterus
C. Phenylketonuria
D. Galactosemia
Kernicterus
154
A high concentration of which of the following in the amniotic fluid might suggest a neural tube defect?
A. Lecithin
B. Alpha-fetoprotein
C. Kernicturus
D. Creatine
B. Alpha-fetoprotein
155
The sclerotome arises from the cells located in the
Notochord
Paraxial mesoderm
Intermediate mesoderm
Lateral plate mesoderm
None of above
Paraxial mesoderm
156
The cardiogenic plate arises from
Embryonic mesoderm
Somatic mesoderm
Splanchnic mesoderm
Intermediate mesoderm
Neural crest
Splanchnic mesoderm
157
An inductive stimulus from which structure stimulates the transformation of epithelial sclerotome into 2ary mesnchyme?
Neural crest
Somite
Ectodermal placodes
Embryonic endoderm
Notochord
Notochord
158
Which of these structueres in the embryo is unsegmented?
Somitomeres
Neuromeres
Notochord
Somites
Notochord
159
The intermediate mesoderm is the precursor of the
Urogenital system
Heart
Somites
Body wall
Vertebral bodies
Urogenital system
160
Which cellular component of the epidermis is a peripheral outpost of the immune system and functions to present antigens to other immune cells?
Merkel cells
Keratinocytes
Basal cells
Melanocytes
Langerhans' cells
Langerhans' cells
161
Which myogenic regulatory factor is expressed latest in development of a muscle fiber
Myogenin
myoD
MRF-4/ myf-6
Myf-5
Pax-3
Myf-4/ myf-6
162
Which of the following molecules plays an important role in determination of dorsoventral axis of developing limb?
Msx-1
Wnt-7
Hoxd-13
Pax-1
FGF-8
Wnt-7
163
What molecule is associated with myogenic cells migrating into the limb bud from somites?
Shh
BMP-7
FGF-4
Pax-3
En-1
Pax-3
164
In the developing limb the SSH gene product is produced in the
Progress zone
Region of interdigital cell death
ZPA
AER
Common muscle mass
ZPA
165
The C.tissue of the limb arises from the
Paraxial mesoderm
Neural crest
Intermediate mesoderm
Somatic mesoderm
Lateral mesoderm
Lateral mesoderm
166
The cell bodies of the motoneurons of a spinal nerve arise from the
Basal plate
Marginal zone
Floor plate
Roof plate
Alar plate
Basal plate
167
An infant with a tuft of hair over the lumbar region of the vertebral column undergoes surgery for a congenital anomily in that region. During surgery it was found that the dura and arachnoid layers over the spinal cord were complete, but that the neural arches of several vertebra were missing. What condition did the infant have?
Meningocele
Meningomyelocele
Encephalocele
Spina bifida occulta
rachischisis
Spina bifida occulta
168
Growth cones adhere strongly to a substrate containing
Acetylcholine
Laminin
Epinephrine
Norepinephrine
Sonic Hedghog
Laminin
169
Complete failure of the neural tube to close in the region of the spinal cord is
Spina bifida occulta
Meningocele
Cranioschisis
Rachischisis
Myelomeningocele
Rachischisis
170
Rhombomeres are segmented division of the
Forebrain
Midbrian
Hindbrain
Spinal cord
None
Hindbrain
171
Which of these cells and tissue types from cranial but not trunk, neural crest cells?
Sensory ganglia
Adrenal medulla
Melanocytes
Schawann cells
None of the above
None of the above
172
\*\*What is one of the major enzymes in the acrosome that breaks down the intercellular matrix?
Acrosin
Hyaluronidase
Lipase
Zona lysin
Hyaluronidase
173
Neural crest arise from the
Somite
Dorsal non-neural ectoderm
Neural tube
Splanchnic mesoderm
Yolk sac endoderm
Neural tube
174
6 month- old infant exhibits multiple congenital defects, including cleft palate, deafness, ocular hypertelorism, and a white forelock but otherwise but otherwise dark hair on his head. The probable diagnosis is
CHARGE association
Von Recklinghausen's disease
Hirchsprung's disease
Waardenburg's syndrome
None of the above
Waardenburg's syndrome
175
What molecule involved in migration of neural crest from the neural tube?
Slug / Snail
BMP-2
Mash 1
Norepinephrine
Glial growth factor
Slug / Snail
176
Which is not a derivative of the neural crest?
Sensory neurons
Motor neurons
Schwann cells
Adrenal medulla
Dental papilla
Motor neurons
177
What maintains the competence of neural crest cells to differentiate into autonomic neurons?
Sonic hedgehog
Acetylcholine
Mash 1
Glial growth factor
Transforming growth factor Beta
Mash 1
178
If trunk neural crest cells are transplanted into cranial region, they can form all the following types of cells except:
Pigments cells
Schawann cells
Sensory neurons
Cartilage
Autonomic neurons
Cartilage
179
Neural-crest derived cells constitute a significant component of which tissue of the eye
Neural retina
Lens
Optic nerve
Cornea
None
Cornea
180
The optic placode arises through an inductive message given off by the
Telencephalon
Rhombencephalon
Infundibulum
Diencephalon
Mesencephalon
Rhombencephalon
181
What molecule plays a role in guidance of advancing retinal axons through the optic nerve
Pax2
FGF3
BMP4
PAX6
BMP7
Pax2
182
Surface ectoderm is induced to become corneal epithelium by an inductive event originating in the
Optic cup
Chordamesoderm
Optic vesicle
Lens vesicle
Neural retina
Lens vesicle
183
The second pharyngeal arch contributes to the
Cochlea and earlobe
Auditory tube and incus
Stapes and earlobe
Auditory tube and stapes
Otic vesicle and stapes
Stapes and earlobe
184
15. In the formation of limb joints, which of the following signal molecules is responsible for inhibiting BMP in the region of the future joint cavity?
Shh
Noggin
Wnt-1
Eng-1
Noggin
185
16. Pre-muscle cells in the developing limb bud are derived from which of the following sources?
Lateral plate mesoderm
Somatic dermatomes
Somitic myotomes
Neural crest
Somitic myotomes
186
The morphology of specific muscles within the limb bud is determined by which of the following factors?
Surrounding connective tissue
BMPs
Apical ectodermal ridge
Noggin
Surrounding connective tissue
187
18. Which of the following is observed when the forelimb rudiment of a salamander embryo is removed so that the limb fails to develop?
The associated spinal ganglia increase more than 150% of their normal size
Local nerves are not affected
The nerves of the brachial plexus remain smaller (thinner) than they would have been if the limb were still there.
Nerves of the future brachial plexus undergo apoptosis
The nerves of the brachial plexus remain smaller (thinner) than they would have been if the limb were still there.
188
Which of the following occurs when an additional limb bud is transplanted into the immediate vicinity of the host forelimb of a salamander embryo?
Neither limb bud will be supplied by any branches of the brachial plexus
The brachial plexus nerves will develop branches running out to the additional limb and will supply it
The transplanted limb bud will be supplied by local nerves that would normally supply flank muscles
Local brachial plexus nerves deviate form the normal limb bud and supply only the transplanted limb bud
The brachial plexus nerves will develop branches running out to the additional limb and will supply it
189
190
\*\*How many germ cells are ovulated?
400
191
\*\*How many germ cells are present at embryonic midterm?
7 million
192
\*\* How many germ cells at birth?
2 million
193
\*\*How many germ cells survive to puberty?
400,000
194
\*\*What induces overlying ectoderm to convert to neural ectoderm?
Transcription factors?
Signals?
Notochord
TF: Foxa-2 and Goosecoid
Signals: Noggin and Chordin
195
\*\*The proliferation phase is characterized by what hormone?
Progesterone
Estrodial
LH
FSH
Secreted by what?
Estradiol by granulosa cells
196
The secretory phase is controlled by rising levels of what?
Progesterone
Estradiol
LH
FSH
Secreted by what?
Progesterone secreted by granulosa and thecal cells
197
\*\*What is the most important enzyme involved in the penetration of the zona pellucida?
Acrosin
198
\*\*The isthmic organizer is located where?
What is it?
Mesencephalon and Metencephalon
Signaling Center
199
\*\*What is the principal signaling molecule for the Isthmic organizer?
What does it do?
FGF-8 (Wnt-1 also)
Organizes and polarizes midbrain and cerebellum
200
\*\*What organizes and polarizes midbrain and cerebellum?
FGF-8 and Wnt-1 of Isthmic organizer
201
\*\*What signaling center is important in teh organizing telecephalon, parts of dienecephalon, olfactory area, adn pituitary gland?
And what signals?
Anterior neural ridge
Shh and FGF-8
202
\*\*What organizes borders between dorsal and ventral thalamus ?
What signal?
Zona limitans
Shh
203
\*\*Amnion (4)
From
Derivative
Two tissues
Inner cell mass
Epiblast deriative
Ectoderm & Mesoderm
204
\*\*Yolk Sac (4)
From
Derivative
Two tissues
Inner cell mass
Hypoblast derivative
Endoderm & Mesoderm
205
Chorion (3)
From
Two tissues
Part of fetal maternal surface
Ectoderm and Mesoderm
206
\*\* Allantois (4)
From
Interfaces with
Two tissues
Inner cell mass
Interfaces iwth placenta via umbilical cord
Endoderm adn Mesoderm
207
\*\* What directly interfaces withthe maternal uterine CT?
Cytotrophoblast
208
\*\* Absence of normal cell death
Syndactyly
209
\*\*Failure of migration example
Pelvic kidneys
210
\*\*Failure to fuse or merge example
Cleft palate
211
\*\*Example of defective fields
Sirenomelia
212
\*\*Occipital cervical boundary
Hox3
213
\*\*Cervical thoracic boundary?
Hox6
214
\*\*Attached floating ribs boundary
Hox9
