ANATOMY (PART 1)

Question 1

Which of the following structures is retroperitoneal?
a. Descending and Ascending colon
b. Ileum
c. Transverse colon
d. Spleen

Answer 1

a. Descending and Ascending colon
Rationale: Retroperitoneal structures are those that lie behind the peritoneum. The ascending and descending colon are retroperitoneal, while the ileum, transverse colon, and spleen are intraperitoneal.

Question 2

The anterior compartment of the arm is innervated by which nerve?
a. Axillary
b. Musculocutaneous
c. Radial
d. Ulnar

Answer 2

b. Musculocutaneous
Rationale: The musculocutaneous nerve innervates the muscles in the anterior compartment of the arm, which includes the biceps brachii, brachialis, and coracobrachialis muscles.

Question 3

During the early stages of tuberculosis infections, the costal parietal pleura becomes inflamed and results in pain at the involved area. What nerve carries these painful sensations?
a. Intercostal nerve
b. Recurrent laryngeal nerve
c. Vagus nerve
d. Phrenic nerve

Answer 3

a. Intercostal nerve
Rationale: The costal parietal pleura is innervated by the intercostal nerves, which carry pain sensations when this pleura becomes inflamed.

Question 4

A patient presenting with an enlarged pupil, ptosis of the lid, and peripheral facial palsy on the right may have a lesion compressing these nerves:
a. CN IV and VII
b. CN III, IV, and VI
c. CN III and VII
d. CN III, IV, and V

Answer 4

c. CN III and VII
Rationale: CN III (oculomotor nerve) is responsible for pupil constriction and eyelid elevation. CN VII (facial nerve) is responsible for facial expressions. A lesion affecting these nerves can result in the described symptoms.

Question 5

This structure is a cell station to all the main sensory systems except the olfactory. This is the –
a. Thalamus
b. Basal ganglia
c. Somesthetic cortex
d. Caudate nucleus

Answer 5

a. Thalamus
Rationale: The thalamus acts as a relay station for sensory information except for the olfactory system, which bypasses the thalamus and directly projects to the olfactory cortex.

Question 6

The vagus nerve accompanies which of the following through the diaphragm?
a. Aorta
b. Phrenic nerve
c. Inferior vena cava
d. Esophagus

Answer 6

d. Esophagus
Rationale: The vagus nerve passes through the diaphragm alongside the esophagus via the esophageal hiatus.

Question 7

In a positive Thompson test, which of the following statements is true?
a. The foot moves into eversion
b. The foot moves into dorsiflexion
c. The foot moves into plantar flexion
d. The foot does not move

Answer 7

d. The foot does not move
Rationale: A positive Thompson test, also known as the Simmonds’ test, indicates a rupture of the Achilles tendon. When the calf is squeezed, the foot does not move (does not plantarflex) if the tendon is ruptured.

Question 8

Which of the following layers provides a natural cleavage plane for surgical separation of the costal pleura from the thoracic wall?
a. Endothoracic fascia
b. Parietal pleura
c. Deep fascia
d. Visceral pleura

Answer 8

a. Endothoracic fascia
Rationale: The endothoracic fascia provides a natural cleavage plane between the parietal pleura and the thoracic wall, facilitating surgical procedures.

• Pleural Cavities & Pleura:
  • Endothoracic Fascia:
    
    • Fibro-areolar tissue located at the inner side of the thoracic wall.
    • Outside the pleura.
    • Not part of the pleura.
    • Tissue located between the inner side of the thoracic wall and the parietal pleura.
  • Pleura (2 Layers):
    
    • Pleural Cavity:
      
      • Pyramidal shape.
      • Surrounded by the pleura.
      • Developing lungs invaginates pleura without destroying it.
    • Visceral Pleura:
      
      • Completely covers the outer surfaces of the lungs (all around) and extends into the depths of the interlobar fissures.
      • Covers the lungs, invaginating the space in the pleural cavity.
    • Parietal Pleura:
      
      • Lines the thoracic wall.
      • Covers the thoracic surface of the diaphragm and the lateral aspect of the mediastinum.
      • Remains attached to the thoracic wall, diaphragm, and mediastinum, not taking part in covering the lungs.
      • 4 Subdivisions:
        
        • Costal Pleura:
          
          • Thickest; separated from the thoracic wall by endothoracic fascia.
        • Cervical Pleura (Capula):
          
          • Covers the apex of the lung; covered by Sibson’s fascia.
          • Apex:
            
            • Extends higher than the 1st rib and clavicle.
            • At the root of the neck; prone to injury.
        • Diaphragmatic Pleura:
          
          • Very thin; meets the costal pleura at two places: sternal reflection and vertebral reflection.
        • Mediastinal Pleura:
          
          • Meets with the visceral pleura.
          • Pleural passageway:
            
            • Upper Part: Root of the lungs (hilum).
            • Lower Part: Empty, hence forms the pulmonary ligament.
      • Sensory Nerves:
        
        • Closer to the chest wall (lateral/outer half) & central portion: Intercostal nerves.
        • Phrenic nerves.

Question 9

When foreign objects are aspirated into the trachea, they will usually pass into the right primary bronchus because:
a. It is at a 90-degree angle to the trachea
b. It is more curved, longer, and smaller than the left
c. It is straighter, longer, and larger than the left
d. It is larger, straighter, and shorter than the left

Answer 9

d. It is larger, straighter, and shorter than the left
Rationale: The right primary bronchus is wider, more vertical, and shorter than the left, making it the more likely path for aspirated objects.

Question 10

Side-to-side curvature of the vertebral column is best viewed on an AP view as:
a. Lordosis
b. Gomphosis
c. Scoliosis
d. Kyphosis

Answer 10

c. Scoliosis
Rationale: Scoliosis refers to the lateral (side-to-side) curvature of the spine, which is best observed in an anteroposterior (AP) radiographic view.

Question 11

The planning of sequential movements of the entire body and the conscious assessment of errors are controlled by the:
a. Intermediate zone of the cerebral hemispheres
b. Cerebellar tonsils
c. Vermis
d. Lateral zone of the cerebral hemispheres

Answer 11

d. Lateral zone of the cerebral hemispheres
Rationale: The lateral zone of the cerebellar hemispheres is involved in the planning of complex, sequential movements and the conscious assessment of movement errors.

Question 12

Which structure forms the superior border of the femoral triangle?
a. Adductor longus
b. Sartorius
c. Inguinal ligament
d. Gracilis

Answer 12

c. Inguinal ligament
Rationale: The inguinal ligament forms the superior border of the femoral triangle, with the sartorius muscle forming the lateral border and the adductor longus muscle forming the medial border.

Question 13

The roof of the ischiorectal fossa is formed by which of the following?
a. Levator ani
b. Obturator internus muscle
c. Urogenital diaphragm
d. Obturator fascia

Answer 13

a. Levator ani
Rationale: The levator ani muscle forms the roof of the ischiorectal (ischioanal) fossa, while the obturator internus forms the lateral wall.

Question 14

Which muscle divides the neck into an anterior and posterior triangle?
a. Trapezius
b. Platysma
c. None of the above
d. Sternocleidomastoid
e. Sternohyoid

Answer 14

d. Sternocleidomastoid
Rationale: The sternocleidomastoid muscle divides the neck into the anterior and posterior triangles, with the anterior triangle lying in front of the muscle and the posterior triangle lying behind it.

Question 15

Pleural space into which lung tissue just above the cardiac notch would tend to expand during deep inspiration is:
a. Costomediastinal recess
b. Cupola
c. Costodiaphragmatic recess
d. Anterior mediastinum

Answer 15

a. Costomediastinal recess
Rationale: The costomediastinal recess is the pleural space into which the lung tissue expands during deep inspiration, especially around the cardiac notch.

Question 16

Bifid spinous processes are seen in which vertebral region?
a. Cervical
b. Sacral
c. Thoracic
d. Lumbar

Answer 16

a. Cervical
Rationale: Bifid spinous processes are characteristic of the cervical vertebrae (specifically C2 to C6), where the spinous process splits into two parts.

Question 17

Which of the following DOES NOT cross the pelvic brim?
a. Uterine artery
b. Vas deferens
c. Ureters
d. Middle sacral artery

Answer 17

a. Uterine artery
Rationale: The uterine artery does not cross the pelvic brim. It originates from the internal iliac artery and courses within the pelvis. The vas deferens, ureters, and middle sacral artery all cross the pelvic brim.

Question 18

Lesions that interrupt the visual pathway at the chiasma opticum like pituitary tumors cause:
a. Superior quadrantanopsia
b. Homonymous hemianopsia
c. Bitemporal hemianopsia
d. Complete blindness of one eye

Answer 18

c. Bitemporal hemianopsia
Rationale: Lesions at the optic chiasma, such as those caused by pituitary tumors, typically cause bitemporal hemianopsia, which is the loss of vision in the outer (temporal) halves of the visual field of both eyes.

Question 19

The apex of the heart is formed by the:
a. Left atrium
b. Right atrium
c. Left ventricle
d. Right ventricle

Answer 19

c. Left ventricle
Rationale: The apex of the heart is formed by the left ventricle and is located at the left fifth intercostal space at the midclavicular line.

Question 20

The phase of the menstrual cycle that coincides with the activity of the corpus luteum is which of the following?
a. Menstrual phase
b. Secretory phase
c. Luteal phase
d. Proliferative phase

Answer 20

b. Secretory phase
Rationale: The secretory phase of the menstrual cycle coincides with the activity of the corpus luteum, which secretes progesterone to prepare the endometrium for potential implantation of an embryo.

Question 21

Which muscle is innervated by the femoral nerve?
a. Semitendinosus
b. Sartorius
c. Gracilis
d. Gluteus medius

Answer 21

b. Sartorius
Rationale: The sartorius muscle is innervated by the femoral nerve. The semitendinosus is innervated by the tibial part of the sciatic nerve, the gracilis by the obturator nerve, and the gluteus medius by the superior gluteal nerve.

Notes:
o Flex the Thigh/ Extend the Leg./QF: Extend the Leg.
Femoral Vein/Artery

Question 22

Which muscle is innervated by the median nerve?
a. Adductor pollicis
b. Flexor digiti minimi
c. 1st lumbrical
d. Palmaris brevis

Answer 22

c. 1st lumbrical
Rationale: The first and second lumbricals are innervated by the median nerve. The adductor pollicis is innervated by the ulnar nerve, the flexor digiti minimi by the ulnar nerve, and the palmaris brevis by the ulnar nerve.

Question 23

The left lung is made up of how many lobes?
a. 2
b. 1
c. 4
d. 3

Answer 23

a. 2
Rationale: The left lung has two lobes: the superior and inferior lobes, separated by the oblique fissure.

Question 24

This nerve is sensory to the skin covering the tip of the nose:
a. CN VII
b. CN V2
c. CN V3
d. CN V1
e. None of the above

Answer 24

d. CN V1
Rationale: The tip of the nose is innervated by the ophthalmic branch (V1) of the trigeminal nerve (CN V).

Question 25

A fracture on the middle third of the left humeral shaft will most likely injure which nerve? a. Median nerve b. Axillary nerve c. Radial nerve d. Ulnar nerve

Answer 25

c. Radial nerve Rationale: A fracture of the humeral shaft is most likely to injure the radial nerve, which runs in the radial groove of the humerus.

Question 26

Which structure serves as a key landmark for locating neurovascular structures in the gluteal region? a. Gluteus medius b. Quadratus femoris c. Piriformis d. Superior gemellus

Answer 26

c. Piriformis Rationale: The piriformis muscle serves as a key landmark in the gluteal region because the sciatic nerve and other neurovascular structures pass either above or below it.

Question 27

Which one stimulates the release of TSH from the anterior pituitary gland? a. Low thyroglobulin in the thyroid b. Low blood T3 and T4 level c. High iodide content d. High calcium level

Answer 27

b. Low blood T3 and T4 level Rationale: Low levels of T3 and T4 in the blood stimulate the hypothalamus to release TRH, which in turn stimulates the anterior pituitary gland to release TSH.

Question 28

A 20 y/o female was brought to UPHRMC due to an immediate hypersensitivity reaction. Which cell types are responsible for this condition? a. Mast cell b. Adipose cell c. Plasma cell d. Macrophage

Answer 28

a. Mast cell Rationale: Immediate hypersensitivity reactions are mediated by mast cells, which release histamine and other mediators in response to allergens.

Question 29

Mr. Baba Dugo was admitted due to malabsorption syndrome. His BP was 80/50, has pale skin and paper white conjunctiva. Complete blood count was requested. If his hemoglobin count is 6-7 grams, what is the problem of Mr. Baba? a. Leukemia b. Neutrophilia c. Thrombocytopenia d. Anemia

Answer 29

d. Anemia Rationale: A hemoglobin count of 6-7 grams indicates severe anemia, which can cause symptoms such as low blood pressure, pale skin, and pale conjunctiva.

Question 30

The following are main components of the nasal septum, EXCEPT: a. None of the above b. Cribriform plate c. Perpendicular plate of ethmoid bone d. Septal cartilage e. Vomer

Answer 30

b. Cribriform plate Rationale: The main components of the nasal septum are the perpendicular plate of the ethmoid bone, the vomer, and the septal cartilage. The cribriform plate is part of the ethmoid bone but does not form part of the nasal septum.

Question 31

All pharyngeal muscles are innervated by the vagus nerve (CN X), EXCEPT: a. Salpingopharyngeus b. Stylopharyngeus c. Constrictor muscles d. None of the above e. Palatopharyngeus

Answer 31

b. Stylopharyngeus Rationale: The stylopharyngeus muscle is innervated by the glossopharyngeal nerve (CN IX), while the salpingopharyngeus, constrictor muscles, and palatopharyngeus are innervated by the vagus nerve (CN X).

Question 32

This part of the auricle is devoid of cartilage: a. All of the above b. Opening of external acoustic meatus c. Ear lobe d. Tragus e. Helix

Answer 32

c. Ear lobe Rationale: The ear lobe is the only part of the auricle that is devoid of cartilage. The other parts mentioned (opening of external acoustic meatus, tragus, helix) contain cartilage.

Question 33

Which muscle is innervated by the tibial nerve? a. Tibialis anterior b. Peroneus brevis c. Extensor digitorum longus d. Soleus

Answer 33

d. Soleus Rationale: The tibial nerve innervates the soleus muscle. The tibialis anterior, peroneus brevis, and extensor digitorum longus are innervated by the deep peroneal (fibular) nerve and the superficial peroneal (fibular) nerve.

Question 34

The superior and inferior gluteal arteries arise from the: a. Inferior epigastric artery b. Superior rectal artery c. Internal iliac artery d. Common iliac artery

Answer 34

c. Internal iliac artery Rationale: The superior and inferior gluteal arteries arise from the internal iliac artery.

Question 34

This branch of the facial nerve innervates the mentalis muscle: a. Zygomatic b. Buccal c. Mandibular d. Temporal e. Cervical

Answer 34

c. Mandibular Rationale: The mandibular branch of the facial nerve (CN VII) innervates the mentalis muscle. The other branches (zygomatic, buccal, temporal, cervical) innervate different muscles of facial expression.

Question 35

Stimulation of the Vagus nerve will make the heart: a. Cause the heart to have missed beats b. Dysrhythmic c. Bradycardic d. Tachycardic

Answer 35

c. Bradycardic Rationale: Stimulation of the vagus nerve decreases heart rate, causing bradycardia.

Question 36

The glottis is the structure most directly concerned with voice production, and is related to the: a. Vocal folds b. Vestibule c. Infraglottic cavity d. Ventricle e. Vocal cords

Answer 36

a. Vocal folds

Question 37

Increased resistance to pulmonary blood flow in the lungs would cause a direct strain on which chamber of the heart? a. Left ventricle b. Right ventricle c. Left atrium d. Right atrium

Answer 37

b. Right ventricle Rationale: Increased resistance to pulmonary blood flow increases the workload on the right ventricle, which pumps blood to the lungs.

Question 38

Which of the following factors does not influence the testicular temperature to regulate spermatogenesis? a. Rich pampiniform plexus b. Presence of tunica albuginea c. Cremasteric muscle contraction d. Scrotal sweat evaporation

Answer 38

b. Presence of tunica albuginea Rationale: The presence of the tunica albuginea does not play a direct role in regulating testicular temperature. The rich pampiniform plexus, cremasteric muscle contraction, and scrotal sweat evaporation are involved in temperature regulation.

Question 39

A stethoscope placed over the left second intercostal space just lateral to the sternum would be best positioned to direct sounds associated with which heart valve? a. Aortic b. Mitral c. Pulmonary d. Tricuspid

Answer 39

c. Pulmonary Rationale: The left second intercostal space, just lateral to the sternum, is the best position to auscultate the pulmonary valve.

Question 40

The main superficial draining vein of the fronto-parietal lobe is the -- a. Inferior sagittal sinus b. Vein of Rolando c. Vein of Galen d. Vein of Labbe

Answer 40

b. Vein of Rolando Rationale: The vein of Rolando (also known as the central sulcus vein) is the main superficial draining vein of the fronto-parietal lobe. The other options are related to different parts of the brain's venous system.

Question 41

A fracture on the medial epicondyle of the right humerus will most likely injure which nerve? a. Musculocutaneous nerve b. Median nerve c. Radial nerve d. Ulnar nerve

Answer 41

d. Ulnar nerve Rationale: The ulnar nerve passes posterior to the medial epicondyle of the humerus and is susceptible to injury with fractures at this location.

Question 42

The trachea bifurcates into right and left primary bronchi at the level of the: a. Seventh cervical vertebra b. Suprasternal (or jugular) notch c. Plane of the sternal angle d. First rib

Answer 42

c. Plane of the sternal angle Rationale: The trachea bifurcates at the level of the sternal angle, which corresponds to the T4/T5 vertebral level.

Question 43

The prostate gland lies: a. Within the urogenital diaphragm b. At the neck of the bladder and above the pelvic diaphragm c. At the neck of the bladder and below the pelvic diaphragm d. In the superficial perineal space

Answer 43

b. At the neck of the bladder and above the pelvic diaphragm Rationale: The prostate gland is located at the neck of the bladder and lies above the pelvic diaphragm.

Question 44

The central nervous system is derived from this germ layer: a. Mesenchyme b. Ectoderm c. Mesoderm d. Endoderm

Answer 44

b. Ectoderm Rationale: The central nervous system (CNS) is derived from the ectoderm germ layer.

Question 45

Lymphatic vessels from the anal canal, below the pectinate line, drain into which lymph nodes? a. Para-aortic b. Superior mesenteric c. Internal iliac d. Superficial inguinal

Answer 45

d. Superficial inguinal Rationale: Lymphatic drainage from the anal canal below the pectinate line flows to the superficial inguinal lymph nodes.

Question 46

A 65 y/o patient was diagnosed to have cancer of the prostate, which of the following zones is most frequently involved? a. Central zone b. Transition zone c. Peripheral zone d. Superior zone

Answer 46

c. Peripheral zone Rationale: The peripheral zone of the prostate is the most common site for prostate cancer.

Question 47

The ligament that extends from the anterior superior iliac spine to the pubic tubercle and forms the lower lateral boundary of the abdominal wall, is the: a. Lacunar b. Interfoveolar c. Ilio-pectineal d. Inguinal

Answer 47

d. Inguinal Rationale: The inguinal ligament extends from the anterior superior iliac spine to the pubic tubercle and forms the lower lateral boundary of the abdominal wall.

Question 48

Neuronal degeneration in the substantia nigra is the cause of this disease: a. Diplegia b. Hemiplegia c. Parkinson’s disease d. Quadriparesis

Answer 48

c. Parkinson’s disease Rationale: Parkinson’s disease is characterized by neuronal degeneration in the substantia nigra, leading to a decrease in dopamine production.

Question 49

The main blood supply to the brain arises from the -- a. Carotid and vertebral arteries b. Innominate artery c. Middle, anterior, and posterior cerebral arteries d. The Circle of Willis

Answer 49

a. Carotid and vertebral arteries Rationale: The brain's main blood supply comes from the carotid and vertebral arteries, which form the Circle of Willis, providing collateral circulation to the brain.

Question 50

The cerebral hemispheres are separated by a cleft which is occupied by a double fold of dura known as -- a. Superior sagittal sinus b. Tentorium c. Falx cerebri d. Inferior sagittal sinus

Answer 50

c. Falx cerebri Rationale: The falx cerebri is a sickle-shaped fold of dura mater that descends vertically in the longitudinal fissure between the cerebral hemispheres.

Question 51

Which of the following nerves passes through the superficial inguinal ring? a. Iliohypogastric nerve b. Lateral femoral cutaneous nerve c. Ilioinguinal nerve d. Obturator nerve

Answer 51

c. Ilioinguinal nerve Rationale: The ilioinguinal nerve passes through the superficial inguinal ring, providing sensory innervation to the skin of the groin and the upper part of the genitalia.

Question 52

The uterine tube runs in the free border of a double-layered sheet of peritoneum clothing the anterior and posterior surfaces of the uterus and attaching laterally to the pelvic wall. This sheet is known as the: a. Mesovarium b. Recto-uterine fold c. Mesouterus d. Broad ligament

Answer 52

d. Broad ligament Rationale: The broad ligament is a double-layered sheet of peritoneum that supports the uterus, fallopian tubes, and ovaries, extending from the sides of the uterus to the walls and floor of the pelvis.

Question 53

The dorsal root of the spinal nerves carries: a. Motor fibers b. Parasympathetic fibers c. Mixed fibers d. Afferent fibers

Answer 53

d. Afferent fibers Rationale: The dorsal root of spinal nerves carries sensory (afferent) fibers that transmit sensory information from the body to the spinal cord. Summary (Spinal cord): Gray Matter: AME/PSA * Anterior (Ventral) Horn: Motor neurons, efferent root. * Posterior (Dorsal) Horn: Sensory neurons, afferent root. White Matter: Columns/Funiculus > Tracts * Anterior Tracts: Located between anteromedian and anterolateral fissures. * Lateral Tracts: Located between anterolateral and posterolateral fissures. ->Lateral Corticospinal Tracts: Descending motor tracts for voluntary movement. ->Rubrospinal Tracts: Descending motor tracts for fine-tuning motor control.

Question 54

Which of the following structures is NOT found in the mediastinum? a. Heart b. Lungs c. Great vessels d. Trachea

Answer 54

b. Lungs Rationale: The lungs are located in the pleural cavities on either side of the mediastinum. The mediastinum contains the heart, great vessels, trachea, esophagus, and other structures.

Question 55

Infected glands of the anus (near the pectinate line) may erode the wall of the anal canal and rupture laterally into the: a. Retropubic space b. Deep perineal pouch (or space) c. Rectovesical fossa d. Ischiorectal fossa

Answer 55

d. Ischiorectal fossa Rationale: Infected anal glands near the pectinate line can erode through the wall of the anal canal and rupture into the ischiorectal (ischioanal) fossa, leading to abscess formation.

Question 56

The "porta hepatis" of the liver transmits all of the following EXCEPT the: a. Hepatic arteries b. Hepatic veins c. Hepatic ducts d. Portal vein

Answer 56

b. Hepatic veins Rationale: The porta hepatis transmits the hepatic arteries, hepatic ducts, and portal vein, but not the hepatic veins, which drain directly into the inferior vena cava.

Question 57

This nerve divides the posterior cervical triangle into equal superior and inferior parts: a. Great auricular b. None of the above c. Spinal accessory nerve d. Lesser occipital e. Supraclavicular

Answer 57

c. Spinal accessory nerve Rationale: The spinal accessory nerve (CN XI) traverses the posterior cervical triangle and divides it into superior and inferior parts.

Question 58

A 45 y/o female consults an endocrinologist due to tremor at rest, hypertension, loss of weight, and exophthalmia. Which one is the most probable problem of the patient? a. Hyperthyroidism b. Adult hypothyroidism c. Hyperparathyroidism d. Hashimoto's disease

Answer 58

a. Hyperthyroidism Rationale: The symptoms described are characteristic of hyperthyroidism, which includes increased metabolism, weight loss, tremor, hypertension, and exophthalmos (protruding eyes).

Question 59

Which muscle is innervated by the superficial peroneal nerve? a. Tibialis anterior b. Peroneus longus c. Peroneus tertius d. Plantaris

Answer 59

b. Peroneus longus Rationale: The superficial peroneal nerve innervates the peroneus longus and peroneus brevis muscles, which are involved in eversion and plantarflexion of the foot. The tibialis anterior and peroneus tertius are innervated by the deep peroneal nerve, and the plantaris is innervated by the tibial nerve. Legs: Anterior (Dorsiflex/Extends): DEEP Peroneal Nerve -Tibialis Ant./Extensor Longus/Peroneus Tertius Lateral (Eversion/Plantarflex): Superficial Peroneal Nerve -Peroneus Longus/Brevis

Question 60

When you inhale, the diaphragm: a. Does not move b. Moves downward c. Relaxes d. Moves upward

Answer 60

b. Moves downward Rationale: During inhalation, the diaphragm contracts and moves downward, increasing the volume of the thoracic cavity and allowing air to enter the lungs. ### Muscles of Respiration **Primary Muscles:** 1. **Diaphragm**: Main muscle for inhalation, increases thoracic cavity volume. 2. **Intercostal Muscles**: - **External Intercostals**: Elevate ribs during inhalation. - **Internal Intercostals**: Depress ribs during forced exhalation. **Accessory Muscles:** 1. **Scalene Muscles**: Elevate first two ribs. 2. **Sternocleidomastoid**: Elevates sternum. 3. **Pectoralis Minor**: Elevates ribs during deep inhalation. **Muscles of Forced Exhalation:** 1. **Abdominal Muscles**: Compress abdominal organs, forcing diaphragm up. 2. **Internal Intercostals**: Depress ribs during forced exhalation.

Question 61

Insulin is released by the pancreatic islets when it is stimulated by which of the following? a. Elevated blood glucose level b. Inhibition of pancreatic enzyme production c. Increased pancreatic polypeptide d. Accelerated conversion of glycogen to glucose

Answer 61

a. Elevated blood glucose level Rationale: Insulin is released by the beta cells of the pancreatic islets in response to elevated blood glucose levels.

Question 62

The common bile duct, hepatic artery, and portal vein are found grouped together in the: a. Gastrosplenic ligament b. Gastrohepatic ligament c. Gastrocolic ligament d. Hepatoduodenal ligament

Answer 62

d. Hepatoduodenal ligament Rationale: The common bile duct, hepatic artery, and portal vein are grouped together in the hepatoduodenal ligament, which forms part of the lesser omentum.

Question 63

The cerebellar cortex has three functional areas, the cortex of the vermis influences movements of the -- a. Axial parts of the body b. Lateral parts of the body c. Distal parts of the body d. Proximal parts of the body

Answer 63

a. Axial parts of the body Rationale: The cortex of the vermis influences movements of the axial parts of the body, such as the trunk.

Question 64

The most prominent projection in the posterior part of the skull is called: a. Inferior nuchal line b. Superior nuchal line c. External occipital protuberance d. Inion

Answer 64

d. Inion The term "inion" refers to the most prominent point of the external occipital protuberance. Therefore, this is essentially another term for the external occipital protuberance.

Question 65

In the male, the membranous urethra: a. Is that part within the corpus spongiosum b. Starts at the trigone of the bladder c. Is that part within the prostate gland d. Is that part within the urogenital diaphragm

Answer 65

d. Is that part within the urogenital diaphragm Rationale: The membranous urethra is the portion of the male urethra that passes through the urogenital diaphragm.

Question 66

The scrotum has as its counterpart in the female the: a. Labia minora b. Labia majora c. Crura of the clitoris d. Clitoris

Answer 66

b. Labia majora Rationale: The labia majora in females are homologous to the scrotum in males.

Question 67

Jefferson's fracture involves which vertebrae? a. C-1 b. C-7 c. C-2 d. C-4

Answer 67

a. C-1 Rationale: Jefferson's fracture is a burst fracture of the atlas (C-1 vertebra) typically caused by axial loading.

Question 68

A fracture of the head of the fibula will most likely injure which structure? a. Popliteal artery b. Common peroneal nerve c. Tibial nerve d. Great saphenous vein

Answer 68

b. Common peroneal nerve Rationale: The common peroneal nerve winds around the neck of the fibula and is vulnerable to injury with fractures in this area.

Question 69

The pacemaker of the heart is the: a. SA node b. Bundle of His c. Purkinje system d. AV node

Answer 69

a. SA node Rationale: The sinoatrial (SA) node is the natural pacemaker of the heart, responsible for initiating the electrical impulses that set the heart rate.

Question 70

This paranasal sinus is located posterior to the orbit: a. None of the above b. Sphenoid c. Ethmoidal d. Maxillary e. Frontal

Answer 70

b. Sphenoid Rationale: The sphenoid sinus is located posterior to the orbit. The ethmoidal sinuses are located between the nose and the eyes, the maxillary sinuses are below the orbits, and the frontal sinuses are above the orbits.

Question 71

The cerebellum receives information from the cerebral cortex, muscles, tendons, joints, vestibular nuclei, cortico-bulbar tracts. All information is fed into the cerebellar circuitry by -- a. Efferent fibers b. Intrinsic fibers c. Arbor vitae d. Mossy and Climbing fibers

Answer 71

d. Mossy and Climbing fibers Rationale: Mossy and climbing fibers are the primary afferent inputs to the cerebellum, carrying information from various sources.

Question 72

The pleura: a. Doesn't extend into fissures of the lung b. Is wholly innervated by both the intercostal and phrenic nerves c. Extends upwards into the neck above the medial 1/3 of the clavicle d. Has the same surface markings as the lungs

Answer 72

c. Extends upwards into the neck above the medial 1/3 of the clavicle Rationale: The pleura extends into the neck above the medial third of the clavicle. It also extends into the fissures of the lungs and is innervated by both intercostal and phrenic nerves, but it does not have the same surface markings as the lungs.

Question 73

Overdistension of the valves of the atrioventricular orifices of the heart is prevented by the papillary muscles and the: a. Ligamentum venosum b. Ligamentum teres c. Trabeculae carneae d. Chordae tendineae

Answer 73

d. Chordae tendineae Rationale: The chordae tendineae are tendinous cords that connect the papillary muscles to the atrioventricular valves, preventing valve prolapse during ventricular contraction.

Question 74

In superficial lacerations of the scalp, the wound does not gape due to the strength of this layer: a. Connective tissue b. Aponeurosis epicranialis c. Pericranium d. Loose areolar tissue e. Skin

Answer 74

b. Aponeurosis epicranialis Rationale: The aponeurosis epicranialis (also known as the galea aponeurotica) provides strength and prevents gaping of superficial scalp wounds.

Question 75

The ischiocavernosus muscle is found in the: a. True pelvis b. Superficial perineal space c. Ischiorectal fossa d. Deep perineal space

Answer 75

b. Superficial perineal space Rationale: The ischiocavernosus muscle is located in the superficial perineal space, helping maintain erection by compressing the outflow veins.

Question 76

Which test is used to diagnose De Quervain's tenosynovitis? a. Allens b. Phalens c. Tinels d. Finkelsteins

Answer 76

d. Finkelsteins Rationale: Finkelstein's test is used to diagnose De Quervain's tenosynovitis, which involves pain and swelling of the tendons on the thumb side of the wrist.

Question 77

The heart is located in which anatomical subdivision of the mediastinum? a. Superior b. Posterior c. Anterior d. Middle

Answer 77

d. Middle Rationale: The heart is located in the middle mediastinum, which also contains the pericardium, roots of the great vessels, and other structures.

Question 78

A fracture-dislocation of the left shoulder will most likely injure which nerve? a. Axillary nerve b. Ulnar nerve c. Radial nerve d. Musculocutaneous nerve

Answer 78

a. Axillary nerve Rationale: The axillary nerve is commonly injured in shoulder dislocations due to its close proximity to the humeral head and the shoulder joint.

Question 79

The POSTERIOR boundary of the epiploic foramen (of Monro) is the: a. Caudate lobe of the liver b. First part of the duodenum c. Inferior vena cava d. Portal vein

Answer 79

c. Inferior vena cava Rationale: The inferior vena cava forms the posterior boundary of the epiploic foramen (also known as the foramen of Winslow), which is the communication between the greater and lesser sacs of the peritoneal cavity.

Question 80

Which of the following structures lies between the azygos vein and the thoracic aorta in the posterior mediastinum of the thorax? a. Thoracic duct * b. Pericardiacophrenic artery c. Left posterior superior intercostal vein d. Right superior intercostal vein

Answer 80

a. Thoracic duct Rationale: The thoracic duct is the major lymphatic vessel that runs between the azygos vein and the thoracic aorta in the posterior mediastinum.

Question 81

The afferent pathway for the corneal reflex is: a. CN V b. CN VI c. CN IV d. CN III

Answer 81

a. CN V Rationale: The afferent pathway for the corneal reflex is via the ophthalmic branch of the trigeminal nerve (CN V), which senses the touch on the cornea.

Question 82

The dorsal aspect of the tongue is divided into the oval and pharyngeal parts by: a. Foramen cecum b. Lingual frenulum c. Sulcus terminalis d. Vallate papillae

Answer 82

c. Sulcus terminalis Rationale: The sulcus terminalis is a V-shaped groove that divides the dorsal surface of the tongue into the anterior two-thirds (oral part) and the posterior one-third (pharyngeal part).

Question 83

Which one contributes to the stability and strength of the cornea? a. Bowman's membrane b. Inner stratified squamous epithelium c. Descemet's membrane d. Substantia propria

Answer 83

d. Substantia propria Rationale: The substantia propria (also known as the stroma) is the thickest layer of the cornea and provides its primary strength and stability due to its dense collagen fibers.

Question 84

The brachioradialis muscle is innervated by which nerve? a. Radial b. Ulnar c. Musculocutaneous d. Median

Answer 84

a. Radial Rationale: The brachioradialis muscle is innervated by the radial nerve.

Question 85

In the human kidney, the renal papilla projects directly into the: a. Renal columns b. Ureter c. Major calyx d. Minor calyx

Answer 85

d. Minor calyx Rationale: The renal papilla projects directly into the minor calyx, which collects urine from the pyramids.

Question 86

Which of the following is located at the opening between the small and large intestines? a. Cardiac sphincter b. Ileocecal valve c. Ligament of Treitz d. Pyloric sphincter

Answer 86

b. Ileocecal valve Rationale: The ileocecal valve is located at the junction of the small intestine (ileum) and the large intestine (cecum).

Question 87

Which intraocular muscle is innervated by the abducent nerve? a. None of the above b. Superior rectus c. Lateral rectus d. Superior oblique e. Inferior oblique

Answer 87

c. Lateral rectus Rationale: The lateral rectus muscle, which abducts the eye, is innervated by the abducent nerve (CN VI).

Question 88

A 30-year-old female went to an ENT specialist due to vertigo. The specialist examined her and found out that the patient has nystagmus. Lesion of which of the following does not cause nystagmus? a. Cerebellum b. Brain stem c. Visual system d. Cerebrum

Answer 88

d. Cerebrum Rationale: Nystagmus is typically caused by lesions in the cerebellum, brain stem, or visual system, but not in the cerebrum.

Question 89

This anterior neck subtriangle contains the cervical viscera: a. Submental b. Submandibular c. Occipital d. Carotid e. Muscular

Answer 89

e. Muscular Rationale: The muscular triangle of the anterior neck contains the cervical viscera, including the thyroid and parathyroid glands, larynx, and trachea.

Question 90

The ligamentum arteriosum is: A. Remnant of a fetal channel connecting the right atrium to the left atrium B. Remnant of the embryonic umbilical artery C. A ligament connecting the liver to the anterior abdominal wall D. A fibrous remnant of a fetal channel connecting the left pulmonary artery to the aorta

Answer 90

D. A fibrous remnant of a fetal channel connecting the left pulmonary artery to the aorta Rationale: The ligamentum arteriosum is a remnant of the ductus arteriosus, a fetal blood vessel that connects the left pulmonary artery to the aorta.

Question 91

The abdominal aorta passes through the diaphragm at which vertebral level? A. T12 B. T6 C. T8 D. T10

Answer 91

A. T12 Rationale: The abdominal aorta passes through the aortic hiatus of the diaphragm at the T12 vertebral level.

Question 92

The final control of the parasympathetic system is in the: A. Medial hypothalamic nucleus B. Supraoptic nucleus C. Suprachiasmatic nuclei D. Pre-optic and anterior nuclei of the hypothalamus

Answer 92

D. Pre-optic and anterior nuclei of the hypothalamus Rationale: The pre-optic and anterior nuclei of the hypothalamus are involved in the control of the parasympathetic nervous system.

Question 93

When considering the structures that make up the thoracic wall, which of the following is most superficial? A. Subserous (or extrapleural) fascia B. External intercostal muscles C. Internal intercostal muscle D. Intercostal vessels and nerve

Answer 93

B. External intercostal muscles Rationale: The external intercostal muscles are the most superficial muscles in the thoracic wall, lying just under the skin and subcutaneous tissue.

Question 94

Which structure below leaves the most pronounced impression on the right lung of the cadaver? A. Azygos vein B. Right phrenic nerve C. Thoracic aorta D. Right vagus nerve

Answer 94

A. Azygos vein Rationale: The azygos vein leaves a pronounced impression on the mediastinal surface of the right lung.

Question 95

Which structure forms the medial wall of the axilla? A. Pectoralis minor B. Serratus anterior C. Pectoralis major D. Subscapularis

Answer 95

B. Serratus anterior Rationale: The serratus anterior muscle forms the medial wall of the axilla.

Question 96

Most of the small intestine receives its blood supply from branches of a single artery. The artery that supplies most of the small bowel is the: A. Superior mesenteric B. Gastroduodenal C. Inferior mesenteric D. Celiac

Answer 96

A. Superior mesenteric Rationale: The superior mesenteric artery supplies most of the small intestine, including the jejunum and ileum.

Question 97

This funnel-shaped structure connects the nasopharynx to the middle ear: A. Petrosquamous fissure B. Eustachian tube C. Pyramidal eminence D. Tubal tonsil

Answer 97

B. Eustachian tube Rationale: The Eustachian tube (also known as the auditory tube) connects the nasopharynx to the middle ear, helping to equalize pressure.

Question 98

Paralysis of the serratus anterior is due to involvement of which nerve? A. Axillary B. Suprascapular C. Lateral pectoral D. Long thoracic

Answer 98

D. Long thoracic Rationale: The long thoracic nerve innervates the serratus anterior muscle. Paralysis of this muscle leads to winging of the scapula.

Question 99

What is the most frequently fractured carpal bone? A. Pisiform B. Scaphoid C. Trapezium D. Lunate

Answer 99

B. Scaphoid Rationale: The scaphoid bone is the most frequently fractured carpal bone, often due to falls on an outstretched hand.