T3 AQ Flashcards

1
Q
The morphology of specific muscles within the limb buds is determined by which of the following factors
Surrounding CT
BMPs
Apical ectodermal ridge
Noggin
A

Surrounding connective tissue

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2
Q
Pre muscle cells in the developing limb bud are derived from which of the following sources?
Lateral plate mesoderm
Somatic dermatomes
Somatic myotomes
Neural crest
A

Somatic myotomes

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3
Q

Which of the following represents the principal function of the AER?
Stimulating outgrowth of the limb bud
Setting up the AP axis of the limb bud
Determining the specific characteristic of the ectodermal appendages of the limb
Determining the pattern of neural outgrowth of the lomb

A

Stimulating outgrowth of the limb bud

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4
Q

If the limb disc of a salamander embryo is rotated 180 degrees, so that both the AP and the DV axes are revered, which of the following would be observed?
The resulting limb would be completely normal with no reversal of axes
The AP axis of the resulting limb would be reversed but not the DV axis
The DV axis of the resulting limb bud would be revered but not the AP axis
Both the AP and the DV axes of the resulting limb would be revered

A

The AP axis of the resulting limb would be reversed but not the DV axis

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5
Q
Numerous experiments have shown that retinoic acid is capable of inducing the formation of the posterior limb in vertebrates. RA is not the actual morphogen but is capable of activating which of the following genes, which is thought to express the actual morphogen?
Shh
Wnt-7
Pax-3
Noggin
A

Shh

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6
Q
Pattern formation along the proximodistal axis of the limb bud is primarily determined by which of the following?
Paxa
Hoxd
Retinoic acid
Shh
A

Hoxd

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7
Q
The presence of webbing between the toes of wading birds such as ducks and the presence of webbed fingers (syndactyly) is most likely associated with which of the following?
Overexpression of noggin
Oligohydramnios
Reduced apoptotic activity
Amniocentesis
A

Reduced apoptotic activity

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8
Q

Which of the following experiments carried out on salamander embryos illustrates that the developing limb is a highly regulative system?
Split a limb primordium in two halves and prevent them from fusing
Juxtapose two equivalent halves of a limb primordium
Remove part of a limb primordium
All of the above

A

All;
Split a limb primordium in two halves and prevent them from fusing
Juxtapose two equivalent halves of a limb primordium
Remove part of a limb primordium

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9
Q
Which of the following factors functions as the initial initiator of future hindlimb development?
Hoxd 
Tbx4
Shh
Gli3
A

Tbx4

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10
Q

In limb development, the attraction oft he outgrowing nerves to peripheral organs seems to be unspecified to a very high degree. Connections between a nerve and the end organ can be made only if the two correspond to each other. These assumptions are based on which of the following experiments?
An eye was transplanted tot eh side of a salamander embryo after the forelimb rudiment was removed
A salamander forelimb bud was removed and replaced by a hindlimb bud
A salamander limb rudiment was transplanted to the flank (side) of a host salamander
An obstacle (piece of mica) was placed between the spinal cord and the region where the hindlimb rudiment was to develop in a salamander embryo

A

An eye was transplanted tot eh side of a salamander embryo after the forelimb rudiment was removed

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11
Q
During limb development, pre-muscle cells in the somite express c-met, which is the receptor for which of the following?
Pax3
N-cadherin
Tcf-4
Scatter factor
A

Scatter factor

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12
Q
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
A

Noggin

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13
Q

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 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 from the normal limb bud and supply only the transplanted limb bud.

A

The brachial nerves will develop branches running out to the additional limb and will supply it

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14
Q

The formation of clubfoot () is associated with which of the following?
A misplaced ZPA
Defective cellular migration from somites
Thalidomide
Oligohydramnios
Neural crest defect

A

Oligohydramnios

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15
Q

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 to 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

A

The nerves of the brachial plexus remain smaller (thinner) than they would have been if the limb were still there

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16
Q
Which of the following are NOT derived from neural crest cells?
Postganglionic autonomic neurons
Autonomic ganglia
Sensory neuron cell bodies
Motor neuron cell bodies
A

Motor neuron cell bodies

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17
Q

Trunk neural crest cells utilize three migratory pathways. The earliest (first) emigrating cells following which of the following pathways?
Ventral/sympathoadrenal
Ventrolateral
Dorsolateral

A

Ventral pathway/Sympathoadrenal pathway

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18
Q
Cranial neural crest cells from region of rhombomeres 6 and 7 are involved in the establishment of which of the following structures?
Pharyngeal arch 1
Pharyngeal arch 2
Pharyngeal arch 3
Pharyngeal arch 4
A

Pharyngeal arch 3

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19
Q
Neural crest cells that give rise to the leaflets of the semilunar valves, thymus, thyroid and parathyroid glands, and the septa that divide the conus arteriosus into the aortic and pulmonary arteries arise from which of the following?
Circumpharyngeal 
Vagus
Cardiac
Cranial
A

Cardiac neural crest cells

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20
Q

What neurocristopathies is characterized by pigmentation defects, white stripe in the hair, deafness, and cleft palate among others?

A

Waardenburg Syndrome

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21
Q

A low concentration of what factors results in placode formation, which a high concentration of the same factor results in the formation of neural plate?

A

BMP

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22
Q

What factor is referred to as the “master gene of eye development” in Drosophila and in human eye development is necessary to induce the formation of the lens placode?

A

Pax-6

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23
Q

In the development of the retina, the nasotemporal (anterior-posterior) axis is fixed first (before the dorsoventral axis). This axis is established, in part, by gradients composed of what?

A

Ephrins

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24
Q

Except for pharyngeal arch musculature, the rest of the pharyngeal arch mesenchyme is derived from what source?

A

Neural crest

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25
``` Except for the first pharyngeal pouch, patterning of the pharyngeal arch endoderm is heavily based on exposure to which of the following factors? BMPs Retinoic acid FGF10 Shh ```
Retinoic acid
26
Shaping of the snout involves the establishment of a gradient between what pairs of signals?
FGF8 and Shh
27
What develops from the cartilaginous portion of the second pharyngeal arch?
Stapes
28
``` The palate forms during which of the following time periods? 1-3 weeks 4-5 weeks 6-10 weeks 11-15 weeks ```
6-10 weeks
29
``` Cranial neural crest cells from region of rhombomere 4 is involved in the establishment of which of the following structures? Pharyngeal arch 1 Pharyngeal arch 2 Pharyngeal arch 3 Pharyngeal arch 4 ```
Pharyngeal arch 2
30
``` Cranial neural crest cells from region of rhombomeres 1 and 2 are involved in the establishment of which of the following structures? Pharyngeal arch 1 Pharyngeal arch 2 Pharyngeal arch 3 Pharyngeal arch 4 ```
Pharyngeal arch 1
31
``` Tendons of limb muscles arise from the lateral plate mesoderm. Limb muscles arise from which of the following sources? Dorsal lip of the myotome Ventral buds of myotomes Ventrolateral dermomyotome Paraxial somitomeres ```
Ventrolateral dermomyotome
32
``` 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
33
``` Pre-muscle cells in the developing limb bud are derived from which of the following sources Lateral plate mesoderm Somitic dermatomes Somitic myotomes Neural crest ```
Somitic myotomes
34
Which of the following represents the principle function of the AER? Stimulating outgrowth of the limb bud Setting up the AP axis of the limb bud Determining the specific characteristics of the ectodermal appendages of the limb Determining the pattern of neural outgrowth of the limb
Stimulating outgrowth of the limb bud
35
If the limb disc of a salamander embryo is rotated 180 degrees, so that both the AP and the DV axes are reversed, which of the following would be observed? The resulting limb about be completely normal with no reversal of axes The AP axis of the resulting limb would be revered but not the DV axis The DV axis of the resulting limb would be revered but not the AP axis Both the AP and DV axes of the resulting limb would be reversed
The AP axis of the resulting limb would be reversed but not the DV axis
36
``` Numerous experiments have shown that retinoic acid is capable of induing the formation of the posterior limb in vertebrates. Retinoic acid is not the actual morphogen but is capable of activating which of the following genes, which is thought to express the actual morphogen? Sonic Hedgehog Wnt 7 Pax 3 Noggin ```
Sonic Hedgehog
37
``` Pattern formation along the proximodistal axis of the limb bud is primarily determined by which of the following? Pax a Hox d RA Shh ```
Hoxd gene
38
``` The presence of webbing between the toes of wading birds such as ducks and the presence of webbed fingers (syndactyly) is most likely associated with which of the following? Overexpression of Noggin Oligohydramnios Reduced apoptotic activity Amniocentesis ```
Reduced apoptotic activity
39
Which of the following experiments carried out on salamander embryos illustrates that the developing limb is a highly regulative system? Split a limb primordium into two halves and prevent them from fusing Juxtapose two equivalent halves of a limb primordium Remove part of a limb primordium All of the above
All of the above
40
``` Which of the following factors functions as the initial initiator of future hindlimb development? Hoxd Tbx4 Shh Gli3 ```
Tbx4
41
In limb development, the attraction of the outgrowing nerves to peripheral organs seems to be unspecific to a very high degree. Connections between a nerve and the end organ can be made only if the two correspond to each other. These assumptions are based on which of the following experiments? An eye was transplanted to the side of the salamander embryo after the forelimb rudiment was removed A salamander forelimb bud was removed and replaced by a hindlimb bud A salamander limb rudiment was transplanted to the flank (side) of a host salamander An obstacle (piece if mica) was placed between the spinal cord and the region where the hindlimb rudiment was to develop in a salamander embryo
An eye was transplanted to the side of the salamander embryo after the forelimb rudiment was removed
42
``` During limb development, pre-muscle cells in the somite express c-met, which is the receptor for which of the following? Pax 3 N-cadherin Tcf-4 Scatter factor ```
Scatter factor
43
``` 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
44
Which of the following occurs when 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 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 from the normal limb bud and supply only the transplanted limb bud
The brachial nerves will develop branches running out to the additional limb and will supply it
45
The formation of club foot (tapiles equinovarus) is associated with which of the following A misplaced ZPA Defective cellular migration from somites Thalidomide Oligohydramnios A neural crest defect
Oligohydramnios
46
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 to 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
47
``` Which of the following are NOT derived from neural crest cells? Postganglionic autonomic neurons Autonomic neurons Sensory neuron cell bodies Motor neuron cell bodies ```
Motors neuron cell bodies
48
``` Which of these cell and tissue types arise from cranial but not trunk, neural crest cells? Sensory ganglia Adrenal medulla Melanocytes Schwann cells None of the above ```
None of the above
49
``` Which of the following is a poor substrate for migrating neural crest cells? Laminin Chondroitin sulfate Fibronectin Type IV collagen Hyaluronic acid ```
Chondroitin sulfate
50
``` Neural crest cells arise from which of the following? Somite Dorsal non-neural ectoderm Neural plate Splanchnic mesoderm Yolk sac mesoderm ```
Neural plate
51
``` A 65 month old infant exhibits multiple congenital defects, including cleft palate, deafness, ocular hypertelorism, and a white forelock but otherwise dark hair on his head. Which of the following represents a probable diagnosis? CHARGE association Von Recklinghausen's disease Hischsprung's disease Waardenburg's syndrome None of the above ```
Waardenburg's syndrome
52
``` Which of the following is involved in the migration of neural crest cells from the neural tube? Snail BMP 2 Mash 1 Norepinephrine Glial growth factor ```
Snail
53
``` Which is not a derivative of neural crest? Sensory neurons Motor neurons Schwann cells Adrenal Medulla Dental Papilla ```
Motor neurons
54
``` What maintains the competence of neural cells to differentiate into autonomic neurons? Shh ACh Mash 1 Glial growth factor TGF-B ```
Mash 1
55
``` If trunk neural crest cells are transplanted into the cranial region, they can form all of the following types of cells except: Pigement cells Schwann cells Sensory neurons Cartilage Autonomic neurons ```
Cartilage
56
``` Which of the following syndromes is characterized by reduced function of thymus, thyroid and parathyroid glands, cardiovascular defects, and abnormalities of the aortic arches, and is the result of a defect in the neural crest supplying the third and fourth pharyngeal arches? Neurofibromas DiGeorge's syndrome Waardenburg's syndrome CHARGE ```
DiGeorge's syndrome
57
``` Most neural crest cells originating from areas of somites 1-3 will follow the circumpharyngeal path and will make up which of the following divisions? Cardiac neural crest Vagal neural crest Sympathoadrenal neural crest Spinal ganglia neural crest ```
Cardiac neural crest
58
Which of the following conclusions concerning the choroid fissure is correct? The optic nerve and the hyaloid artery both use the choroid fissure to reach the posterior chamber of the eye Low concentrations of Shh are necessary to guide the axons of the ganglion cells along the choroid fissure to the retina Failure of the choroid fissure to close results in the formation of cyclopia The hyaloid artery uses the choroid fissure to reach the posterior chamber of the eye
The hyaloid artery uses the choroid fissure to reach the posterior chamber of the eye
59
``` Neural crest derived cells constitute a significant component of what tissue of the eye? Neural retina Lens Optic nerve Cornea None of the above ```
Cornea
60
``` What molecule play a role in guidance of advancing retinal axons through the optic nerve? Pax 2 FGF 3 BMP 4 Pax 6 BMP 7 ```
Pax 2
61
``` Surface ectoderm is induced to become corneal epithelium by an inductive event originating in which of the following? Optic cup Chordamesoderm Optic vesicle Lens vesicle Neural retina ```
Lens vesicle
62
``` Which of the following is caused by failure of the choroid fissures to close during the sixth week of pregnancy? Anophthalmos Microphthalamos Cyclopia Colobomo ```
Colobomo
63
``` Antagnostic actions ofBMP-4 and Shh, along with ventropin, establish which of the following axes? AP axis of the cornea AP axis of the lens Dorso-ventral axis of the retina Nasal-temporal fields of the retina ```
Dorso-ventral axis of the retina
64
``` Except for the pharyngeal muscles, pharyngeal arch mesoderm (tendons, etc) are derived from which of the following? Neural crest Somitomeres Paraxial mesoderm Parachordal mesoderm ```
Neural crest
65
``` Shaping the snout involved the establishment of a gradient between which of the following pairs of signals? FGF 8 and Edn1 Hox and Pax TGF2 and BMP 4 FGF 8 and Shh ```
FGF 8 and Shh
66
``` In craniofacial develop, segmentation of the cranial neural tube occurs as a result of expression of which of the following genes? Sox BMP Hox TGF ```
Hox
67
``` In most kind of glandular development, signaling between Shh and FGF occurs between the epithelium and mesenchyme. In which of the following development processes does this signaling occur entirely within the epithelium? Nasal Salivary Thyroid Anterior pituitary ```
Salivary
68
``` 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 morphogenetic events? Formation of future molar cusps Induction of the ameloblast layer Induction of the ondontoblast layer Formation of the dental sac ```
Formation of future molar cusps
69
``` At which of the following stages of tooth development do both the ameloblast and odontoblast layers first appear together? Tooth bud stage Cap stage Bell stage Dental sac stage ```
Bell stage
70
``` Which of the following is necessary for tooth development to continue past the bud stage? BMP 4 Shh FGF 8 Pax 9 ```
Pax 9
71
``` Cleft lip results from lack of fusion of which of the following? Nasomedial and nasolateral processes Nasomedial and maxillary processes Nasolateral and maxillary processes Nasomedial and mandibular processes ```
Nasomedial and maxillary processes
72
``` Which of the following abnormalities in tooth development is characterized by teeth that appear blue-gray or amber brown and are opalescent and may be caused by mutations in type I collagen? Amelogenesis imperfecta Dentinogenesis imperfecta Enamel Fluorosis KGB syndrome ```
Dentinogenesis imperfecta
73
``` Which of the following develops from the cartilaginous portion of the second pharyngeal arch? Meckel's cartilage Malleus Incus Stapes ```
Stapes
74
``` Cranial nerve V innervates structures derived from which of the following pharyngeal arches? Pharyngeal arch 1 Pharyngeal arch 2 Pharyngeal arch 3 Pharyngeal arch 4 ```
Pharyngeal arch 1
75
``` Rathke's pouch arises from which of the following? Diencephalon Stomodeal ectoderm Mesencephalon Pharyngeal endoderm Infundibulum ```
Stomodeal ectoderm
76
``` Expression of which of the following genes is necessary to prevent pharyngeal arch 2 from differentiating into pharyngeal arch 1? Engrail Pax 7 Hoxa 2 Foxd ```
Hoxa-2
77
``` Muscles of facial expression are innervated by cranial nerve 7. This relationship would suggest that these muscle are derived from which of the following pharyngeal arches First Second Third Fourth ```
Second
78
``` In the formation of the mammalian temporomandibular articulation, several bones that are involved in the jaw articulation in lower vertebrates dissociate themselves from jaw articulation and become located in the middle ear cavity where they function in sound transmission. The malleus of the middle ear in mammals is derived from which of the following former jaw articulation bones? Columella Meckel's cartilage Quadrate Articular ```
Articular
79
``` Which of the following develop from the third pharyngeal pouch in response to high concentration of Shh Thyroid Superior parathyroids Thymus Inferior parathyroids ```
Inferior parathyroids
80
``` The auditory tube is a derivative of which of the following pharyngeal pouches? First Second Third Fourth ```
First
81
``` Which of the following remains temporarily connected to the floor of the pharynx by a narrow duct that later forms the foramen cecum on the tongue? Thyroid Thymus Parathyroid Anterior pituitary ```
Thyroid
82
``` Which of the following do NOT form from the ureteric bud (metanephric diverticulum)? Renal pelvis Ureter Nephros Calyces ```
Nephros
83
``` Metanephrogenic blastemata are induced to condense from the surrounding mesenchyme by which of the following? Allantoic sac Mesonephric duct Pronephric duct Ureteric diverticulum ```
Ureteric diverticulum
84
``` Potter's facies is the characteristic of an embryo exposed to which of the following? Exstrophy of the bladder Oligohydramnios Polycystic kidney disease Epispadias ```
Oligohydroamnios
85
``` The ureteric epithelium, influenced by BMP-4, forms which of the following proteins necessary to render the epithelium of the ureter impermeable to water? Sproutys Gremlin Uroplakins Uvomorulins ```
Uroplakins
86
``` Which of the following factors determine the cranio-caudal limits of the early urinary system? Lim 1 Hox 4-11 RA Pax 2 and Pax 8 ```
Hox 4-11
87
``` Sprouty and Gremlin are involved in the development of which of the following? Teeth Kidneys Tongue Salivary glands ```
Kidneys
88
The presence of the SRY gene is directly associated with which of the following? Switching of the indifferent gonad to testis Switching of the indifferent gonad to an ovary Retention of the Mullerian ducts Development of the secondary male characteristics
Switching of the indifferent gonad to testis
89
The scrotum and labia majora develop from which of the following primordia Genital tubercle Genital swellings Genital fold A combination of genital tubercle and the genital swellings
Genital swellings
90
``` In the genetic male, Sertoli cells develop from which of the following? Rete cords Sex cords Efferent ductules Cortex of the indifferent gonad ```
Sex cords (become seminiferous tubules)
91
``` In a genetic male, mesonephric tubules in the vicinity of the gonad will form which of the following? Rete cords Sex cords Efferent ductules Mesonephric duct ```
Efferent ductules
92
``` The conversion of the primordial germ cells into meiosis competent cells depends on which of the following factors? Dazl RA Nanos-2 Stra-8 ```
Dazl
93
``` The internal carotids are derived from which of the following pairs of aortic arches? Third Fourth Fifth Sixth ```
Third
94
``` The hepatic portal vein develops from which of the following fetal vessels? Left vitelline Right vitelline Left umbilical Right umbilical ```
Left umbilical
95
Which of the following best describes the function of the ductus venosus? It will become the left hepatic vein It carried food-laden blood from the yolk sac to the hepatic capillary network It drains the hepatic capillary networks into the sinus venosus It permits the incoming oxygenated placental blood to bypass the capillary networks of the liver
It permits the incoming oxygenated placental blood to bypass the capillary networks of the liver
96
``` The ductus arteriosus shunt in the fetus becomes the ligamentum arteriosus in the adult. It is derived from the dorsal portion of which of the following structures? Right fourth aortic arch Left fourth aortic arch Right sixth aortic arch Left sixth aortic arch ```
Left sixth aortic arch
97
``` Hemangioblasts originate from the posterolateral mesoderm during gastrulation and organize into blood islands in the yolk around day 18. They become divided into two lineages. Which of the following factors is responsible for establishing the endothelial lineage Runx1 Hox 3 VeGF A Angiopoietin ```
Hox 3
98
``` The initial formation of the cardiac tube is guided by which of the following? Tbx 2 Tbx 5 Pax 6 Shh ```
Tbx-2
99
``` During cardiac development, the distal region of the bulbus cordis (outflow tract) is derived from which of the following? Primary cardiac field Secondary cardiac field Neural crest Septoconal ridges ```
Neural crest
100
``` Absence of hand-2 results in the absence of which of the following structures? Right ventricle Left ventricle Left atrium Right atrium ```
Right ventricle
101
``` The proximal region of the outflow tract of the developing heart is derived from which of the following sources? Primary heart field Secondary heart field Neural crest Conotruncal septa ```
Secondary heart field
102
``` Which of the following adult heart components is derived from the secondary heart field? Right ventricle Left ventricle Left atrium Right atrium ```
Right ventricle
103
``` The foramen ovale is a right-left cardiac shunt and is structurally associated with which of the following cardiac structures? Septum primum Septum secundum Foramen primum Foramen secundum ```
Septum secundum
104
What is true concerning the characteristics of the three stages of kidney development in human embryos?
The mesonephros is the functional kidney in the human embryo and the pronephric duct is necessary to form the mesonephric duct.
105
``` Partitioning of the single ventricle into left and right chamber begins during which of the following developmental periods? Third week Fourth week Fifth week Sixth week ```
Fifth week
106
``` The tracheal primordium extends from the ventral flood of the foregut and will later have to be separated from the foregut lumen (future esophagus) by a septum. The separation is accomplished by a pair of lateral ridges that fuse toward the midline from posterior to anterior. Which of the following factors is responsible for initiating the formation of this septum? Wnt Hox6 BMP4 Fox3A ```
Wnt
107
``` The initial sight for the development of the respiratory system is from the floor of the pharynx (ventral foregut). Which of the following factors marks this site (as well as the site of the thyroid diverticulum)? Wnt BMP 4 Nkx2.1 FGF 10 ```
Nkx2.1
108
``` The large, ventral portion of the respiratory diaphragm is derived from which of the following primordia? Pleuropericardial folds Falciform ligament Pleuroperitoneal folds. Septum transversum ```
Septum transversum