Question 1

A 50-year-old woman has diminished sensation in the left part of her face and eyelid. She feels no pain in her left cornea and has no tearing in that eye. A lesion in which of the following areas is most likely to cause these findings?

Accepted Answer

A)   Left frontal lobe
B)   Left motor nucleus of the trigeminal nerve (CN V) 
C)   Left ventral posterolateral (VPL)  nucleus of the thalamus
D)   Ophthalmic division of the left trigeminal nerve
E)   Right nucleus of the trigeminal nerve D

Question 2

Which of the following when administered to a normal individual produces effects similar to that observed in patients with myasthenia gravis?

Accepted Answer

A)   Black widow spider toxin
B)   Neostigmine
C)   Curare
D)   'Nerve gas'
E)   Edrophonium C

Question 3

Insulin binding to its receptor tyrosine kinase leads to:

Accepted Answer

A)   Activation of Janus kinase-signal transducer and activator of transcription (JAK-STAT) 
B)   Mitogen-activated protein kinase (MAPK)  extracellular signal-regulated kinase (ERK)  activation
C)   Insulin-receptor binding to the MAPK promoter
D)   Gs activation and substrate phosphorylation by PKA
E)   Gi activation of phosphodiesterase (PD
E)   B

Question 4

In aging, if osteoclast activity is constant, but osteoblast activity progressively decreases, which disease will likely develop?

Accepted Answer

A)   Osteoclastoma
B)   Osteomalacia
C)   Paget's disease
D)   Osteoporosis
E)   Scurvy

Question 5

A 45-year-old woman experiences blurred vision and difficulty swallowing after eating some home-canned vegetables. These symptoms are followed by respiratory distress and flaccid paralysis. The symptoms of her illness are most associated with which of the following?

Accepted Answer

A)   Black widow spider toxin
B)   Botulinum toxin
C)   Organophosphate poisoning
D)   Benzodiazepine ingestion
E)   ( α\alphaα ) -Bungarotoxins

Question 6

A 24-year-old bicyclist severely injures his right leg after colliding with an automobile. He is hemorrhaging from the wound but is stabilized, with a blood pressure of 90/40 mmHg and a heart rate of 100/min. He was not wearing protective head gear at the time of the accident, but shows no evidence of head trauma. His breathing is rapid and shallow. Blood pressure and urine flow could best be improved in this patient by:

Accepted Answer

A)   Oral administration of diuretic
B)   Administration of physiologic saline solution
C)   Blood transfusion
D)   Indirect cardiac massage
E)   Intravenous injection of norepinephrine

Question 7

Which of the following causes of brain hypoxia would most strongly stimulate the aortic and carotid chemoreceptors?

Accepted Answer

A)   Carbon monoxide poisoning
B)   Severe anemia
C)   Formation of methemoglobin
D)   A marked decrease in pulmonary diffusing capacity
E)   Acute respiratory alkalosis

Question 8

A 58-year-old woman develops a fever and dyspnea approximately 24 h after undergoing a laparoscopic cholecystectomy. Physical examination shows decreased percussion, increased tactile fremitus, and decreased breath sounds in the right lower lobe. Which of the following is the most likely diagnosis?

Accepted Answer

A)   Atelectasis
B)   Lobar pneumonia
C)   Lung abscess
D)   Pulmonary infarction
E)   Spontaneous pneumothorax

Question 9

A tall, obese 14-year-old boy with long arms has bilateral gynecomastia, decreased testicular size for his age, and sparse axillary and pubic hair. A buccal smear preparation shows a single Barr body extending off the nuclear membrane of many squamous cells. Which of the following sets of laboratory studies would be expected in this patient?

Accepted Answer

A)    High High  Low	ext { High} \quad 	ext { High } \quad 	ext { Low} High High  Low  
B)   High  Normal  Normal 	ext {High } \quad 	ext { Normal } \quad 	ext { Normal }High  Normal  Normal  
C)   Low Low  Low 	ext {Low } \quad 	ext {Low } \quad 	ext { Low }Low Low  Low  
D)   Normal High  Low 	ext {Normal } \quad 	ext {High } \quad 	ext { Low }Normal High  Low  
E)   Low Low  High	ext {Low } \quad 	ext {Low } \quad 	ext { High}Low Low  High

Question 10

The glomerular filtration rate (GFR) can be determined from:

Accepted Answer

A)   Urinary flow rate (V) , plasma P-aminohippuric acid (PAH)  concentration (PPAH)  and urinary PAH concentration (UPAH) 
B)   Urinary flow rate (V) , plasma arginine vasopressin (AVP)  concentration (PAVP)  and urinary AVP concentration (UAVP) 
C)   Urinary flow rate (V) , plasma creatinine concentration (Pcreatinine)  and urinary creatinine concentration (Ucreatinine) 
D)   Urinary flow rate (V) , plasma urea concentration (Purea)  and urinary urea concentration (Uurea) 
E)   Urinary flow rate (V) , plasma insulin concentration (Pinsulin)  and urinary insulin concentration (Uinsulin)

Question 11

A 30-year-old man with a family history of sudden cardiac death has a systolic murmur that increases in intensity when he is sitting up. An echocardiogram shows abnormal movement of the anterior mitral valve leaflet against an asymmetrically thickened interventricular septum. The mechanism for sudden cardiac death in this patient's family is most closely attributed to which of the following conditions?

Accepted Answer

A)   Acute myocardial infarction (MI) 
B)   Congenital bicuspid aortic valve
C)   Conduction system defect
D)   Dissecting aortic aneurysm
E)   Mitral valve prolapse (MVP)

Question 12

A 74-year-old comatose man, exhibits flexion of the left upper extremity with passive movement of the head to the right, and flexion of the right upper extremity when the head is moved to the left. His legs are fixed in extension during all movements. Which of the following is the most likely explanation of these findings?

Accepted Answer

A)   Alternating hemiplegia syndrome
B)   Brown-Séquard syndrome
C)   Decerebrate rigidity
D)   Decorticate rigidity
E)   Transection of the spinal cord below vertebra TV

Question 13

You determine that your 1-year-old male patient has cryptorchidism. Cryptorchidism is the term used to describe non-descent of the testes. Which of the following statements is correct in connection with this process?

Accepted Answer

A)   Fertility is unaffected in males with undescended testes.
B)   Hormone treatment is not effective to induce descent.
C)   Leydig cell function is reduced in boys with undescended testes.
D)   There is an increased rate of testicular malignant change in cryptorchidism.
E)   Klinefelter's syndrome may be responsible for testicular non-descent.

Question 14

A healthy 16-year-old man experiences severe hemorrhaging following an automobile accident. He is conscious and aware upon arrival at the emergency department, but hypotensive, and tachypneic. Which of the following is associated with the hemodynamic response to hemorrhage?

Accepted Answer

A)   Decreased coronary blood flow
B)   Decreased sympathetic tone to the venous system
C)   Increased blood flow to the skin, intestines, and kidneys
D)   Increased cholinergic vasoconstrictor tone of skeletal muscle arterioles
E)   Normal cerebral blood flow

Question 15

A 5-year-old boy has a history of growth retardation, pulmonary infections, and bulky, oily, malodorous stools. Which of the following test results would be expected in this patient?

Accepted Answer

A)   Abnormal sweat chloride test
B)   Low C3 complement level
C)   Abnormal nitroblue tetrazolium (NBT)  dye test
D)   Positive wheal and flare reaction with antigen scratch testing
E)   Sputum with Gram-positive diplococci

Question 16

A 23-year-old woman, who complains of chronic cough, shortness of breath, and chest tightness is diagnosed with asthma. Which of the following is the best clinical indicator of significant pulmonary obstruction in patients with asthma?

Accepted Answer

A)   Arterial hypoxemia
B)   Dyspnea
C)   Forced expiratory volume in 1 second (FEV1) /forced vital capacity (FV
C)   ratio of less than 75%
D)   Large anatomic dead space volume
E)   Rapid respirations

Question 17

A patient complains of excessive urine output and constant thirst. Laboratory tests show an elevated plasma sodium concentration (151 mEq/L) and elevated plasma osmolality (320 mOsm/L). The urine osmolality is only 75 mOsm/L. Which of the following could explain the patient's problem?

Accepted Answer

A)   Defective epithelial sodium channel (ENa
C)  
B)   Defective ROMK proteins
C)   Defective V2 receptor proteins
D)   Excessive antidiuretic hormone (ADH)  secretion
E)   Defective atrial natriuretic peptide (ANP)  secretion

Question 18

A 25-year-old woman complains of chronic constipation and progressive weight gain over the past 6 months despite maintaining a pure vegan diet. Physical examination reveals a fatigued woman with brittle hair, face and eyelid puffiness, a symmetrically enlarged, non-tender thyroid gland, prolonged relaxation phase of deep tendon reflexes, and proximal muscle weakness in her lower extremities. Which set of the following results of thyroid function studies shown below would you expect in this patient? $$\begin{array} { l l l l } 
& \begin{array} { l } 
\text { Serum } \
\text { thyroxine } \
\left( \mathrm { T } _ { 4 } \right)
\end{array} & \begin{array} { l } 
\text { Serum } \
\text { thyroid- } \
\text { stimulating } \
\text { hormone } \
\text { (TSH) }
\end{array} & \begin{array} { l } 
131 \mathrm { I } \
\text { (radioactive } \
\text { iodine) } \
\text { uptake }
\end{array} \
\hline \text { A } & \text { Low } & \text { Low } & \text { Low } \
\mathrm { B } & \text { Low } & \text { High } & \text { Nomal } \
\mathrm { C } & \text { High } & \text { Low } & \text { Low } \
\mathrm { D } & \text { High } & \text { Low } & \text { High } \
\mathrm { E } & \text { Normal } & \text { Normal } & \text { Normal }
\end{array}$$

Accepted Answer

A)    Low	ext {Low}Low   \quad \quad Low	ext {Low}Low\quad    \quad Low	ext {Low}Low 
B)    Low  High  Normal \begin{array}{llcc}  	ext {Low   } &  	ext { High } &  	ext { Normal }\\end{array}Low ​ High ​ Normal ​  
C)    High Low  Low \begin{array}{llcc}  	ext { High } & 	ext {Low  } &  	ext { Low }  \\end{array} High ​Low ​ Low ​ 
D)    High  Low  High 	ext { High } \quad 	ext { Low } \quad 	ext { High } High  Low  High  
E)    Normal  Normal  Normal 	ext { Normal } \quad 	ext { Normal } \quad 	ext { Normal } Normal  Normal  Normal

Question 19

An 8-year-old healthy boy is concerned about his very short stature. His growth hormone level is within normal limits despite the fact that his growth rate and bone age are below the norm for children of the same chronologic age. The level of which of the following hormones is most likely to be abnormal?

Accepted Answer

A)   Fibroblast growth (FGF) 
B)   Insulin
C)   Insulin-like growth factor I (IGF-I) 
D)   Somatostatin
E)   Somatotropin

Question 20

A 25-year-old woman has had secondary amenorrhea for the past 8 months. She plans to get married soon, and states that she has been trying to lose weight for her upcoming wedding. A urine pregnancy test is negative. The patient is given an intramuscular injection of progesterone. Ten days later she reports that she has had no withdrawal bleeding. Laboratory studies show the following serum levels: $\begin{array}{|l|l|l|}
\hline&&\text { Normal range }\
\hline \text { Prolactin } & 10 \mathrm{ng} / \mathrm{mL} & 5-10 \mathrm{ng} / \mathrm{mL} \
\hline \text { Follicle-stimulating hormone (FSH) } & 3 \mathrm{mUJ} / \mathrm{mL} & 5-15 \mathrm{~mL} / \mathrm{mL} \
\hline \text { Luteinizing hormone }(\mathrm{LH}) & 2 \mathrm{mUU} / \mathrm{mL} & 5-22 \mathrm{mLU} / \mathrm{mL} \
\hline \text { Thyroid-stimulating hormone }(\mathrm{TSH}) & 4.1 \mu \mathrm{m} / \mathrm{mL} & 10 \mu \mathrm{mL} / \mathrm{mL} \
\hline \text { Estradiol } & 1 \mathrm{ng} / 24 \mathrm{~h} & 0-14 \mathrm{ng} / 24 \mathrm{~h} \
\hline \text { Cortisol (a.m.) } & 35 \mu \mathrm{gL} & 5-25 \mu \mathrm{dL} / \mathrm{dL} \
\hline \text { Growth hormone } & 10 \mathrm{ng} / \mathrm{mL} & <5 \mathrm{ng} / \mathrm{mL}\
\hline
\end{array}$
 Which of the following is the most likely diagnosis?

Accepted Answer

A)   Acromegaly
B)   Cushing's syndrome
C)   Hypopituitarism
D)   Primary ovarian disease
E)   Weight loss syndrome

Exam 2: Physiology of Cells and Molecules