anatomy mcq's 1

19 Pages·2008·0.46 MB·English

by  Dr. Madaan

ANATOMY
MCQ’S 1
RxDENTISTRY

RX DENTISTRY PRESENTS YOU WITH
NEW MCQ’S SERIES . TO START WITH
HERE IS ANATOMY

Dr. MADAAN
2/18/2009
ANATOMY MCQ’S 1

1. The subodontoblastic plexus of Raschkow occurs: 12. Dangerous area of the eye is:
a. Below the cell bodies of odontoblasts a. Ciliary body b. Sclera c. Optic nerve d. Retina
b. In the root region of the pulp
c. Within the central pulp core 13. Urothelium does not line:
d. Within the cell-rich zone of Weil a. Collecting ducts b. Minor calyx
c. Ureter d. Urinary bladder
2. Uppermost structure seen at the hilum of the left lung is:
a. Pulmonary artery b. Pulmonary vein 14. Which type of gingival fibers attaches to cementum of
c. Bronchus d. Bronchial artery adjacent teeth and is present over the alveolar crest?
a. Alveolar crest fibers b. Alveologingival fibers
3. Ulnar injury in the arm leads to all except: c. Transseptal fibers d. Circular fibers
a. Sensory loss of the medial 1/3rd of the hand
b. Weakness of the hypothenar muscles 15. The secretory product of odontoblasts is:
c. Claw hand a. Topocollagen. b. Calcium salts.
d. adduction of thumb c. Mantle dentin. d. Hydroxyapatite.

4. Left renal vein crosses the Aorta: 16. The escapement spaces between teeth and the interdental
a. Anteriorly, above the superior mesenteric artery spaces are called:
b. Anteriorly, below the superior mesenteric artery a. Marginal ridges. b. Contact areas.
c. Posteriorly, at the level of superior mesenteric artery c. Embrasures. d. Developmental grooves
d. Anteriorly, below the inferior mesenteric artery
17. Basement membrane consists of all except:
5. What are intrinsic fibers of cementum? a. Laminin b. Nidogenin
a. Fibers produced by cementoblasts c. Entactin d. Rhodopsin
b. Noncalcified fibers associated with the attachment of
periodontal ligament fibers 18. Perforators are not present at the:
c. Principal fibers of the PDL a. Ankle b. Distal calf
d. None of the above c. Mid thigh d. Below the inguinal ligament

6. In post-ductal coarctation of the aorta, blood flow to the 19. Tongue muscles develops from:
lower limbs in maintained by increased blood flow a. Occipital somites b. Mesoderm of the pharyngeal pouch
through: c. Cervical somites d. Endoderm of pharyngeal pouch
a. Inferior Phrenic and pericardio phrenic vessels
b. Intercostal and Superior epigastric 20. A female come with complaints of chest pain. On
c. Sub costal and Umbilical examination she is found to have pericarditis with
d. Umbilical and superior gastric pericardial effusion. The pain is mediated by:
a. Deep cardiac plexus b. Superficial cardiac plexus
7. Seen in agenesis of corpus callosum is:
c. Phrenic nerve d. Subcostal nerve
a. Astereognosis b. Hemiparesis

c. Hemi sensory loss d. No neurological deficit
21. Meiosis occurs at which of the following transformation:

a. Primary spermatocyte to intermediate spermatocyte
8. One of the following is the watershed area of the colon
b. Primary spermatocyte to secondary spermatocyte
between the superior and inferior mesenteric arteries:
c. Secondary spermatocyte to round spermatid
a. Ascending colon b. Hepatic flexure
d. Round spermatid to elongated spermatid
c. Splenic flexure d. Descending colon

22. The ureter develops from:
9. Gall bladder epithelium is:
a. Metanephros b. Mesonephros
a. Simple squamous b. Simple cuboidal with stereocilia
c. Mesonephric duct d. Paramesonephric duct
c. Simple columnar d. Simple columnar with brush border

23. Inflammation of a retrocaecal appendix will produce
10. Perforating fibers consisting of collagen fibers
pain when there is which of the following movements at
embedded in alveolar bone proper are known as:
the hip:
a. Gingival fibers b. Sharpey’s fibers
a. Flexion b. Extension
c. Transseptal fibers d. Alveolar fibers
c. Medial rotation d. Lateral rotation

11. Which muscle is not punctured while doing a thoracic
24. In Hyaline cartilage, type of collagen present is:
procedure in the mid-axillary line:
a. Type 1 b. Type 2 c. Type 3 d. Type 4
a. Innermost intercostals b. Transverses thoracis

c. External intercostals d. Internal intercostals
25. All of the following statements are true for metaphysis

of bone, except -
a. It is the strongest part of bone.
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b. It is the most vascular part of bone. 37. The communicating vein responsible for spread of
c. Growth activity50 is maximized here. infection from the Dangerous area of the face.
d. It is the region favoring hematogenous spread of a. Superior ophthalmic Vein
infection. b. Inferior Ophthalmic Vein
26. All of the following muscles are grouped together as c. Maxillary Vein
‘muscles of mastication’ except - d. Lingual Vein
a. Buccinator. b.Masseter. c.Temporalis. d.Pterygoids.
38. Artery to vas deferens is a branch of
27. In emergency tracheostomy the following structures are a. Inferior epigastric b. Superior vesical
damaged except: c. Cremasteric d. Middle rectal
a. Isthmus of the thyroid b. Inferior thyroid artery
c. Thyroidea ima d. Inferior thyroid vein 39. What is the origin of the definitive myocardium of the
adult heart?
28. Vidian Nerve is formed by a. Endoderm
a. Deep Petrosal & Greater Superficial Petrosal nerve b. Somatopleuric mesoderm
b. Greater Superficial Petrosal Nerve and Lesser c. Hypoblast
Superficial Petrosal Nerve. d. Splanchnopleuric mesoderm
c. Deep Petrosal Nerve and Lesser Superficial Petrosal
Nerve 40. an infarct causing bilateral infarction of the occipital
d. None of the above lobes is likely to be secondary to occlusion in the
territory of the :
29. Kanavel’s sign is seen in: a. The Posterior Cerebral Artery
a. Tenosynovitis b. Dupuyteren’s contracture b. The Basilar Artery
c. Carpal tunnel syndrome d. Trigger finger c. The superior cerebellar artery
d. The anterior inferior cerebellar artery
30. Which of the following is correctly matched:
a. B cells – Somatostain b. D cells – Insulin 41. Most fascia of the body that attach to bones attach by
c. G cells – Gastrin d. A cells - renin which of the following mechanisms?
a. Blending with the covering periosteum
31. Internal spermatic fascia is derived from b. Inserting deeply into the cancellous bone
a. Transversalis facia c. Inserting deeply into the cartilage
b. Internal abdominis muscle d. Inserting deeply into the diaphysis
c. External Oblique Abdominis Muscle
d. Internal Oblique Abdominis Muscle 42. Which of these statements about Scalenus anterior is
true
32. Sertoli cells in the testis have receptors for: a. Is an accessory muscle of respiration
a. FSH b. LH c. Inhibin d. testosterone b. Lies anterior to the suprascapular artery
c. Is pierced by the phrenic nerve
33. External laryngeal nerve supplies d. Inserts into the scalene tubercle on the second rib
a. Superior Constrictor. b. Middle Constrictor.
c. Inferior constrictor. d. None of the above 43. Which of the following respiratory system components
is derived from neural crest?
34. Most common site of spinal tumour a. Endothelial cells
a. Extramedullary intradural b. Epithelium of primary bronchi
b. Extra dural c. Laryngeal cartilage
c. Intra medullary d. Tracheal glands
d. Extra meduralary extradural
44. An infarct involving the seventh nerve and nucleus is
35. All are essential components of TOF except: likely to be secondary to occlusion in the territory of the:
a. Valvular pulmonic stenosis a. The Posterior Cerebral Artery
b. Right ventricular hypertrophy b. The Basilar Artery
c. Infundibular stenosis c. The superior cerebellar artery
d. Aorta overriding d. The anterior inferior cerebellar artery

36. When stem cell transforms to form other tissues, the 45. A patient has a tumour based in an enlarged jugular
process is called as: foramen , what is the most likely presentation?
a. Dedifferentiation b. Redifferentiation a. Eight cranial nerve palsy
c. Transdifferentiation d. Subdifferentiation b. Ninth cranial nerve palsy
c. Tenth cranial nerve palsy
d. Eleventh cranial nerve palsy

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46. True about diaphragm is pharynx
a. Develops from the septum transversum and cervical d. Is a muscle of mastication
myotomes
b. Receives a nerve supply from phrenic nerve only 56. Nerves that pass in the lateral wall of the cavernous
c. The inferior vena cava passes through the diaphragm at sinus include:
the level of the T12 vertebra a. The ophthalmic division of the trigeminal nerve
d. The aorta passes through the diaphragm at the level of b. The sixth cranial nerve
the T8 vertebra c. The anterior ethmoidal nerve
47. Which cranial nerve exits the skull base at the pars d. The optic nerve
nervosa of the jugular foramen ?
a. Eight cranial nerve palsy 57. The nerve supplying submandibular gland is
b. Ninth cranial nerve palsy a. V b. VII c. IX d. XII
c. Tenth cranial nerve palsy
d. Eleventh cranial nerve palsy 58. The muscle least related to pterygomandibular raphe is
a. Superior pharyngeal constrictor b. Medial pterygoid
48. The following structures pass under the inguinal c. Lateral pterygoid d. Buccinator
ligament
a. The tendon of psoas major 59. The radial nerve
b. The femoral branch of the genitofemoral nerve a. Is the principal branch of the posterior cord of the
c. The long saphenous vein brachial plexus
d. The superficial epigastric vein b. Is derived from the posterior primary rami of the C5 to
T1 nerve roots
49. The axilla contains all except c. Is the main nerve supply to the flexor compartments of
a. The cords of the brachial plexus the arm and forearm
b. The superior thoracic artery d. Supplies sensation to the extensor aspect of the radial
c. The latissimus dorsi muscle in its medial wall three and a half digits
d. The thoracodorsal nerve in its posterior wall
60. The heart of an embryo first begins beating at which of
50. What suspensory ligaments connect the outer edge of the following ages?
the lens of the eye with the ciliary processes? a. 2 weeks b. 3 weeks
a. Zonnules of Zinn b. Zonnules of Schlemm c. 4 weeks d. 6 weeks
c. Cruciate ligaments d. Ligaments of Treitz
61. Which of these statements about oesophagus is true
51. Closure of the neural tube occurs on around which day a. Is 40 cm in length
of the embryonic life period? b. Is lined by stratified squamous epithelium in the upper
a. 26 b. 38 c. 56 d. 74 two-thirds
c. Is lined by transitional epithelium in the lower one-
52. Which of the following is true of the optic disc? third
a. No arteries pass through it d. Drains all of its blood into the azygos and hemiazygos
b. No veins pass through it veins
c. It appears dark red on fundoscopy
d. It is normally less than 1cm in diameter 62. A 36-year-old Asian male complains of difficulty
swallowing. Esophagoscopy reveals a polypoid mass
53. An infarct causes a pure motor herniparesis . This that is subsequently biopsied. In addition to tumor cells,
infarct is likely to be secondary to occlusion in the the esophageal biopsy show normal smooth muscle and
territory of the : striated muscle in the same section. Which portion of
a. The Posterior Cerebral Artery the esophagus was the source of this biopsy?
b. Deep penetrating lacunar artery a. Lower esophageal sphincter
c. The superior cerebellar artery b. Lower third of the esophagus
d. The anterior inferior cerebellar artery c. Middle third of the esophagus
d. Upper esophageal sphincter
54. The most common sex chromosomal aneuploidy in males
is 63. Contraction of which of the following muscles
a. XX karyotype b. XXY karyotype contributes most to the backward movement of the
c. XO karyotype d. XXX karyotype lower jaw during the process of mastication?
a. Digastric b. Lateral pterygoid
55. The buccinator muscle: c. Medial pterygoid d. Temporalis
a. Is attached to both jaws opposite the molar teeth
b. Is supplied by the V nerve 64. Which of the following hormones is secreted by anterior
c. Is continuous with the superior constrictor of the pituitary cells that stain with acidic dyes?
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a. ACTH b. FSH
c. LH d. Prolactin

65. A 7-year-old patient presents with a mass in the anterior
midline of the neck, slightly above the larynx. The mass
is mobile and elevates upon protrusion of the tongue.
This mass is most likely a cyst that developed from
which of the following embryonic structures?
a. First pharyngeal cleft
b. First pharyngeal pouch
c. Second pharyngeal cleft
d. Thyroglossal duct
66. Zygomycosis, a destructive fungal infection of the
sinuses, is likely to reach the brain by which of the
following routes?
a. Cavernous sinus
b. External carotid artery
c. Internal carotid artery
d. Superior sagittal sinus
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b. Failure of formation of the septum secundum
c. Incomplete adhesion between the septum primum and
67. Which of these statements about the thymus gland is septum secundum
false d. Malformation of the membranous interventricular
a. Develops from the fourth pharyngeal pouch septum
b. Decreases in size with age
c. Is made up of cells of endodermal origin 75. Which of the pharyngeal pouches develops into the pal-
d. Descends anterior to the brachiocephalic vein atine tonsil?
a. First b. Second c. Third d. Fourth
68. The morphofunction unit of the breast is composed of:
a. The aveoli and the large duct system 76. During anatomy lab, a medical student notes a fibrous
b. The lobule and the stroma band that runs on the visceral surface of the liver. It is
c. The lactiferous sinus and the terminal ductules attached on one end to the inferior vena cava and on the
d. The TDLU (terminal duct lobular unit) and the large other end to the left branch of the portal vein. In the
duct system embryo, this structure corresponds to the
a. Ductus venosus b. Ligamentum teres
69. What is the length of the Human spermatozooa c. Ligamentum venosum d. Umbilical arteries
(Sperm)?
a. 50 micrometers b. 100 micrometers 77. At which of the following ages does fetal movement first
c. 200 micrometers d. 500 micrometers occur?
a. 1 month b. 2 months c. 4 months d. 6 months
70. Which of the following stimulus does not induce visceral
pain ? 78. A patient, who appears to be female, is found to be 46,
a. Distension b. Pressure XY. The patient's vagina is very shallow, ending in a
c. Cauterisation d. Cutting blind pouch, and there are palpable masses in the labia.
The diagnosis of testicular feminization syndrome is
71. Which of these statements about the pancreas gland is made. Which of the following was most likely present
false during the early fetal life of this individual ?
a. Lies anterior to the left kidney a. A streak ovary
b. Derives part of its blood supply from the splenic artery b. A uterus
only c. Depressed levels of testosterone
c. Has parts in both the supracolic and infracolic d. MIF (Mullerian inhibitory factor)
compartments
d. Is pierced by the middle colic artery 79. The smooth part of the right atrium derives from which
of the following embryonic structures?
72. A 25-year-old female presents to her obstetrician after a. Bulbus cordis b. Primitive atrium
taking a home pregnancy test with a positive result. She c. Primitive ventricle d. Sinus venosus
states that twins run in her family and would like an
ultrasound to determine if she has a twin pregnancy. 80. Which of the following characteristics is similar for
Radiographic studies confirm that the embryo has split spermatogenesis and oogenesis?
at the blastocyst stage. Splitting of the embryo at the a. Age at which meiosis begins
blastocyst stage results in which of the following? b. Amount of cytoplasm retained
a. Conjoined twins c. DNA replication during meiosis
b. Dizygotic twins d. Length of prophase I
c. Fraternal twins
d. Monozygotic twins 81. In a genotypic male, the testes fail to develop, and do
not secrete testosterone or Müllerian regression factor.
73. A newborn male child is noted to have hypospadias. A Which of the following best describes the in utero
complete evaluation determines that the child has no reproductive system development of this individual?
other genitourinary anomalies. Nonetheless, hyposp- a. Both male- and female-type internal reproductive tracts
adias repair will be performed to prevent which of the and male-type external genitalia
following possible sequelae? b. Female-type internal reproductive tract and female-
a. Bladder exstrophy type external genitalia
b. Hydrocele c. Female-type internal reproductive tract and male-type
c. Phimosis external genitalia
d. Urinary tract infection d. Male-type internal reproductive tract and female-type
74. A 12-month-old child is diagnosed with an atrial septal external genitalia
defect. What is the most common cause of such a
congenital heart malformation? 82. Which of these statements about the common bile duct
a. Failure of formation of the septum primum is false
a. Lies in the free edge of the lesser omentum
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b. Lies anterior to the portal vein a. Basale. b. Granulosum.
c. Lies to the right of the hepatic artery c. Corneum. d. Spinosum.
d. Lies anterior to the first part of the duodenum
92. The auriculotemporal nerve encircles which of the
83. From which of the following fetal vessels do the umbil- following vessels?
ical arteries arise? a. Maxillary artery.
a. Aorta b. Superficial temporal artery.
b. Carotid arteries c. Deep auricular artery.
c. Ductus arteriosus d. Middle meningeal artery.
d. Iliac arteries
93. The muscle that is found in the walls of the heart is
84. Thoracic duct is also called characterized by '
a. Hensen’s duct a. A peripherally placed nucleus
b. Bernard’s duct b. Multiple nuclei
c. Pecquet duct c. Intercalated discs
d. Hoffman’s duct d. Fibers with spindle-shaped cells

85. The greater omentum is derived from which of the 94. All of the following are found in the posterior tria-
following embryonic structures? ngle of the neck except one. Which one is the
a. Dorsal mesoduodenum exception?
b. Dorsal mesogastrium a. External jugular vein. b. Subclavian vein.
c. Pericardioperitoneal canal c. Hypoglossal nerve. d. Phrenic nerve.
d. Pleuropericardial membranes
95. Deoxygenated blood from the transverse sinus dra-
86. The lateral pterygoid muscle attaches to which of ins into the _
the following? a. Inferior sagittal sinus
a. Lateral surface of the lateral pterygoid plate. b. Confluence of sinuses
b. Medial surface of the lateral pterygoid plate. c. Sigmoid sinus
c. Lateral surface of the medial pterygoid plate. d. Straight sinus
d. Medial surface of the medial pterygoid plate.
96. The vestigial cleft of Rathke's pouch in the hypop-
87. Which of the following muscles is responsible for hysis is located between the .
the formation of the posterior tonsillar pillar? a. Anterior and posterior lobes
a. Stylopharyngeus. b. Anterior lobe and hypothalamus
b. Tensor veli palatine. c. Posterior lobe and hypothalamus
c. Palatoglossus. d. Median eminence and the optic chiasm
d. Palatopharyngeus.
97. Involution of the thymus would occur following
88. The superior and inferior ophthalmic veins drain which year in a healthy individual?
into the a. 0 years (at birth). b. 12th year.
a. Internal jugular vein c. 20th year. d. 60thyear.
b. Pterygoid plexus
c. Frontal vein 98. Blood from the internal carotid artery reaches the
d. Facial vein posterior cerebral artery by the
a. Anterior cerebral artery
89. The masseter originates from the b. Anterior communicating artery
a. Condyle of the mandible c. Posterior communicating artery
b. Infratemporal crest of the sphenoid bone d. Posterior superior cerebellar artery
c. Inferior border of the zygomatic arch
d. Pyramidal process of the palatine bone 99. The infraorbital nerve is a branch of the
a. Optic nerve
90. Which of the following muscles adducts the vocal b. Oculomotor nerve
cords? c. Ophthalmic nerve
a. Lateral cricoarytenoid. d. Maxillary nerve
b. Posterior cricoarytenoid.
c. Cricothyroid. 100. The most distal portion of the maxillary alveolar bone
d. Vocalis. is the
a. Tuberosity b. Retromolar area
91. Which of the following strata of oral epithelium is c. Palatine raphe d. Palatine fovea
engaged in mitosis?
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1. Ans A. Nerve fibers Pulp and Dentin entering the teeth have been identified histologically as myelinated A-fibers and
unmyelinated C-fibers. These fibers are grouped in bundles and enter through the apical foramina of the teeth, passing through the
radicular to the coronal pulp where they fan out and diverge into smaller bundles. Nerve divergence continues; individuals-fibers
within small bundles lose their myelin sheath and divide repeatedly before finally ramifying into a plexus of single axons known as
the subodontoblastic plexus or plexus of Raschkow. The exact function of this plexus is unknown, as is the changing configuration of
the plexus with dentin formation." From this plexus nerve fibers are distributed toward the pulp-dentin border with terminals showing
a characteristic bead-like structure.

2. Ans A. Explanation: Mnemonic is Atal Bihari Vajpayee (ABV) -Arrangement of pulmonary structures at the hilum of the lungs -
ABV: From (A)bove to below: (A)rtery-(B)ronchus-(v)ein. -Pulmonary artery is uppermost whereas, pulmonary vein is inferior
most. -This applies well to left lung...for right lung one additional bronchus goes above the artery and is called as ep-arterial
bronchus. -Hence, in the right lung the uppermost structure in the hilum will be a bronchus.
NOTE: There are 2 veins which are named anterior & inferior according to their location at the hilum. (Similar arrangement on both
sides) -Bronchus & bronchial arteries are always posterior most structures at the hila of both lungs.

3. Ans D. Explanation: Ulnar nerve supplies the Adductor pollicis muscle and hence it will be paralysed in its lesion. Hence,
adduction of thumb is not a clinical finding in ulnar nerve palsy.

4. Ans B. Explanation: Left renal vein crosses in front of the aorta from right to left towards the left kidney. -Additional information:
The vein lies below the superior mesenteric artery (L-1 vertebral level) and above the renal artery (lies between L-1 & L-2 vertebra)
-Because the inferior vena cava is on the right side of the body, the left renal vein is generally the longer of the two.
- Now, because the inferior vena cava is not laterally symmetrical, the left renal vein often receives the following veins:
left inferior phrenic vein left suprarenal vein
left gonadal vein (left testicular vein in males, left ovarian vein in females) left 2nd lumbar vein
-This is in contrast to the right side of the body, where these veins drain directly into the IVC.

5. Ans A. Classification of Cementum Based on the Nature and Origin of Collagen Fibers.
Organic matrix derived form 2 sources: Periodontal ligament (Sharpey’s fibers)
Cementoblasts
Extrinsic fibers derived from PDL. These are in the same direction of the PDL principal fibers i.e. perpendicular or oblique to the
root surface. Intrinsic fibers derived from cementoblasts. Run parallel to the root surface and at right angles to the extrinsic fibers
The area where both extrinsic and intrinsic fibers is called mixed fiber cementum.

6. Ans B. Explanation: Coarctation (stenosis/narrowing) of aorta is due to defect in the tunica media, which forms a shelf like
projection into the lumen, most commonly in the region of the ductus arteriosus.
-A collateral circulation develops distal to the obstruction between subclavian artery (internal thoracic artery) & descending aorta
(posterior intercostal arteries).
-This anastomosis produces characteristic notching of the ribs on X-RAY
Superior epigastric is a branch of internal thoracic artery and gives the anterior intercostal arteries in the lower intercostal spaces.
-Coarctation of the aorta is of three types:
1. Pre-ductal coarctation: The narrowing is proximal to the ductus arteriosus. If severe, blood flow to the aorta distal (to lower body)
to the narrowing is dependent on a patent ductus arteriosus, and hence its closure can be life-threatening.
2. Ductal coarctation: The narrowing occurs at the insertion of the ductus arteriosus. This kind usually appears when the ductus
arteriosus closes.
3. Post-ductal coarctation: The narrowing is distal to the insertion of the ductus arteriosus. Even with an open ductus arteriosus blood
flow to the lower body can be impaired. Newborns with this type of coarctation may be critically sick from the birth.

7. Ans A. Explanation:
1. Agenesis of the Corpus Callosum (ACC) is a rare birth defect (congenital disorder) in which there is a complete or partial absence
of the corpus callosum. Agenesis of the corpus callosum occurs when the corpus callosum, the band of tissue connecting the two
hemispheres of the brain, does not develop typically in utero. In addition to agenesis of the corpus callosum, other callosal disorders
include hypogenesis (partial formation), dysgenesis (malformation) of the corpus callosum, and hypoplasia (underdevelopment) of the
corpus callosum.
Signs and symptoms: Signs and symptoms of Agenesis of the Corpus Callosum and other callosal disorders vary greatly among
individuals. However, some characteristics common in individuals with callosal disorders include vision impairments, low muscle
tone (hypotonia), poor motor coordination, delays in motor milestones such as sitting and walking, low perception of pain, delayed
toilet training, chewing and swallowing difficulties, early speech and language delays, and social difficulties. Recent research
suggests that specific social difficulties may be a result of impaired face processing. Unusual social behavior in childhood is often
mistaken for or misdiagnosed as Asperger's syndrome or other autism spectrum disorders. Other characteristics sometimes associated
with callosal disorders include seizures, spasticity, early feeding difficulties and/or gastric reflux, hearing impairments, abnormal
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ANATOMY MCQ’S 1

head and facial features, and mental retardation.

8. Ans C. Explanation: -The weakest link in the marginal chain of vessels (of Drummond) is near the left colic (splenic) flexure,
between the middle colic artery (mid-gut) & the left colic artery (hind-gut).
-An inner arterial circle (of Riolan) between the ascending branch of left colic artery and the trunk of middle colic artery may
supplement the blood supply to this region of colon. "Watershed area" is the medical term referring to regions of the body that receive
dual blood supply from the most distal branches of two large arteries, such as the splenic flexure of the large intestine.
During times of blockage of one of the arteries that supply of the watershed area, such as in atherosclerosis, these regions are spared
from ischemia by virtue of their dual supply. However, during times of systemic hypoperfusion, such as in DIC or Heart failure, these
regions are particularly vulnerable to ischemia by virtue of the fact that they are supplied by the most distal branches of their arteries,
and thus the least likely to receive sufficient blood.

9. Ans D. Explanation:
-Gall bladder is lined by columnar cells with irregular microvilli-brush border.
-Small intestine is lined by microvilli arranged in regular fashion -striated border.
-Brush border is also present in the proximal convoluted tubule (PCT) of kidney.
-Stereo-cilia are present in the hair cells of internal ear and epididymis.

10. Ans B. Sharpey's Fibers = direct extensions of dense irregular CT from periosteum into compact bone. Functions to anchor tendon
(with fibers penetrating periosteum to bone) to bone. Formation by appositional bone growth around original attachment site.
The periodontal ligament is much more cellular and more highly vascularized than ordinary ligaments, reflecting its high rate of
protein turnover. It consists of collagen and some elastic fibers. The collagenous fibers penetrate into the cementum and into the
surrounding bone. When properly stained, the fibers within cementum and bone are visible and referred to as Sharpey's fibers.

11. Ans b. Explanation:
-During a thoracic procedure in mid-axillary line, the external & internal intercostal muscles are always punctured.
-Inner most layer : Of the three group of muscles in this layer, the innermost intercostals are at the side of the rib cage,
-Subcostalis are at the back and Transversus thoracis at the front of the thoracic cage.
-Hence, Transversus thoracis will not be punctured in a mid axillary line approach.
NOTE: Transversus thoracis muscle was formerly called as sterno-costalis, more exactly. In fact, now TRANSVERSUS THORACIS
includes all the three inner layer muscles, namely - Subcostalis, innermost intercostal (intercostalis intimi) and the sterno-costalis.

12. Ans A. Explanation:
-The dangerous area of the eye is the region in the neighborhood of the ciliary
Body, and wounds or injuries in this situation are peculiarly dangerous.

13. Ans A. Explanation: -Urothelium (or transitional) epithelium starts in the minor calyx region and lines major calyx, pelvis,
ureter, urinary bladder and the proximal 2 cm of prostatic urethra.
-Collecting ducts are lined by columnar epithelium

14. Ans C. Transseptal fibers
Types of gingival fibers
There are three groups within which gingival fibers are arranged: gingivodental group - there are three types of fibers within this
group: fibers that extend towards the crest of the gingiva fibers that extend laterally to the outer surface of the gingiva and fibers that
extend outward, past the height of the alveolar crest, and then downward along the cortex of the alveolar bone. circular group - these
fibers are unique in that they exist entirely within the gingiva and do not contact the tooth transseptal group - these fibers have
traditionally been described as spanning the interproximal tissue between adjacent teeth, into which they are embedded. However,
two other types of fibers have been described in this group:
semicicular fibers - fibers that run through the facial and lingual gingiva around each tooth, attaching to the interproximal surfaces of
the same tooth.
transgingival fibers - fibers that run between two non-adjacent teeth and are embedded in the cementum of their proximal surfaces,
passing around the tooth in the middle of the two teeth attached with these fibers.

15. Ans C: DENTIN : It consists of about 80% hydroxyapatite (by dry weight) and 20% of organic matrix (collagen, proteoglycans,
glycosaminoglycans) and is pervaded by the dentinal tubules. On the outside, the dentin is covered either by enamel (anatomical
crown) or by cementum. On its inner surface facing the pulp chamber and the root canal, the dentin is lined by the odontoblasts,
which are columnar cells arranged in a single layer (fig. 19). Each odontoblast sends a cytoplasmic process into one dentinal tubule,
reaching as far as 1/2 the thickness of the dentin. Odontoblasts are not separated from the pulp by a basement membrane. A plexus of
capillaries extends within the odontoblast layer close to the predentin (a thin uncalcified layer of dentin matrix facing the pulp
chamber). The odontoblasts are of mesenchymal origin, synthesizing and secreting the components of the dentinal matrix. They
secrete first a layer of predentin, which stains pale in H&E and PAS preparations. The odontoblasts furthermore secrete a
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ANATOMY MCQ’S 1

phosphoprotein that is deposited specifically at the predentin-dentin junction. Apparently this phosphoprotein initiates the
calcification of dentin. Dentin stains strongly with H&E and PAS

16. Ans C. Embrasure: The space between two teeth which opens out from their contact point.

17. Ans D. Explanation: -Rhodopsin is present in the retinal rods -The basement membrane consists of an electron-dense membrane
called the lamina densa, about 30–70 nanometers in thickness, and an underlying network of reticular collagen (type IV) fibrils (its
precursor is fibroblasts) which average 30 nanometers in diameter and 0.1–2 micrometers in thickness. This type IV collagen is of the
reticular type, in contrast to the fibrillar collagen found in the interstitial matrix. -The Lamina Densa (which is made up of type IV
collagen fibers; perlecan (a heparan sulfate proteoglycan) coats these fibers and they are high in heparan sulfate) and the Lamina
Lucida (made up of laminin, integrins, entactins, and dystroglycans) together make up the basal lamina. -Lamina Reticularis attached
to basal lamina with anchoring fibrils (type VII collagen fibers) and microfibrils (fibrilin) is collectively known as the basement
membrane.

18. Ans D. Explanation: -Perforators connect the superficial veins with the deep veins. -There are about 5 perforators along the great
saphenous vein - 1.in the mid-thigh; 2. Below knee; 3, 4 & 5. near the lower leg and ankle. -Great saphenous vein itself drains into the
femoral vein below the inguinal ligament.

19. Ans A. Explanation: -Tongue muscles develop from occipital myotomes and are innervated by the 12 nerve.

20. Ans C. Explanation:
-The pain of pericarditis originates in the parietal layer only and is transmitted by the phrenic nerve.
-The fibrous and parietal layer of serous pericardium is supplied by the phrenic nerve.
-Visceral layer is insensitive.

21. Ans B. Explanation: -Meiosis - I changes primary spermatocyte into secondary spermatocyte.
-Then, Meiosis - II changes secondary spermatocyte into the spermatid.

22. Ans C. Explanation: -Mesonephric duct (Wolffian duct) gives the ureteric bud which further develops into ureter.

23. Ans B. Explanation: Psoas sign: flexion of or pain on hyperextension of the hip due to contact between an inflammatory process
and the psoas muscle; a sign often seen in appendicitis. Called also Cope’s sign.
-The inflamed appendix lies on the psoas muscle and the patient will lie with the right hip flexed for pain relief.
-Extension of hip will cause pain
Rovsing's sign: Rovsing sign, pressure over the point on the left side corresponding to the McBurney point will elicit the typical pain
at the McBurney point on the right side in appendicitis.
-Deep palpation of the left iliac fossa causes pain in the right iliac fossa.
Obturator sign: If an inflamed appendix is in contact with the obturator internus, spasm of the muscle can be demonstrated by flexing
and internally rotating the hip. This manouvre will cause pain in the hypogastrium.

24. Ans B. Explanation:
Hyaline & elastic cartilage contain type-II collagen, whereas fibro-cartilage is more like bone & contain type-I cartilage.

25. Ans A. Metaphysis as we all know is the most metabolically active part of the bone with rapid cell turn over and most vascular
part also. Since it is the most vascular part we have the Osteomyelitis that spreads through hematogenous route originate here in
children and is one of the areas that get fractured in pathological fracturesof the bone. The zone of maturation is more vulnerable
1. It is the weakest part of bone and so this is a wrong statement. 2. It is the most vascular part of bone.
3. Growth activity is maximized here. 4. It is the region favouring hematogenous spread of infection.

26. Ans A. Muscles of Mastication
Muscle Origin Insertion Action
Temporalis Temporal bone Coronoid process Elevates jaw
Parietal bone Retracts jaw
Masseter Zygomatic arch Mandibular angle Elevates jaw
Lateral Pterygoid (Superior Head) Sphenoid bone Temporomandibular Disk Draws articular disk forward
Lateral Pterygoid (Inferior Head) Lateral Side of Lateral Pterygoid Plate Mandibular neck (bilaterally) Protracts jaw
(unilaterally) Abducts jaw
(grinding)
Medial Pterygoid Medial Side of Lateral Pterygoid Plate Mandibular angle Elevates jaw
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