CAS 1 Q 6

A patient develops a form of lung cancer that spreads to occlude the thoracic duct. Edema involving which of the following sites might be expected as a potential complication? A) Entire left side and right leg B) Entire right side and left leg C) Left arm only D) Right arm and right half of head only E) Right arm only

A

A patient with a nerve injury to the gluteal region has di"culty rising from the seated position and straightening his trunk, but he has no di"culty flexing his leg. This nerve injury a!ects the A) gluteus maximus muscle B) gluteus minimus muscle C) hamstring muscles D) iliopsoas muscle E) obturator interns muscle

A

Attributes of allosteric e!ectors include 1) activation of enzymatic activity 2) inactivation of enzymatic activity 3) alteration of the apparent Km for substrate 4) competition with substrate for binding at the active site A) 1,2,3 only B) 1,3 only C) 2,4 only D) 4 only E) All are correct

A

Concerning a 14 day old blastocyst, select the most appropriate structure in the accompanying diagram which is the primary chorionic villi A)AB)BC)CD)DE)EF)FG)G

A

Constituents of the thin filaments of a relaxed skeletal muscle cell include 1) actin 2) tropomyosin 3) troponin 4) S1 fragments of myosin (heavy meromyosin) A) 1,2,3 only B) 1,3 only C) 2,4 only D) 4 only E) All are correct

A

Production of NH3 A) Oxidative deamination of glutamate B) Transamination of glutamate C) Both D) Neither

A

Semiconservative replication involves the separation of parent DNA molecule. Which one of the following protein is essential for the separation of the strands? A) DNA helicase B) DNA polymerase I C) DNA polymerase III D) DNA topoisomerase E) DNA ligase

A

The contractile portions of the muscle spindle are directly supplied by which nerve fibers? A) Gamma motor neurons B) Alpha motor neurons C) Ia a!erent fibers D) II a!erent fibers E) Postganglionic sympathetic fibers

A

The genetic code is said to be "degenerate" because: A) there are more codons than amino acids B) there are more amino acids than codons C) di!erent organisms use di!erent codons to encode the same amino acid D) some codons specify more than one amino acid

A

The lower motor neurons of the pons are found in which groups of nuclei? A) V, VI, and VII B) VI, X, and N. Ambiguus C) XII, N. Ambiguus, and VII D) III, IV, and VI E) V only

A

The nerve supply of the tongue is derived, in part, from the nerve of the 1) first branchial arch (mandibular division of V) 2) second branchial arch (VII) 3) third branchial arch (IX) 4) fourth branchial arch (X) A) 1,2,3 only B) 1,3 only C) 2,4 only D) 4 only E) All are correct

A

The release of epinephrine from the chroma"n granules of the adrenal medulla into the bloodstream in response to neural stimulation is mediated by which of the following? A) Acetylcholine B) Gamma-Aminobutyric acid (GABA) C) Cortisol D) Dopamine E) Serotonin

A

When NADH electrons need to be translocated into the mitochondrion for oxidative phosphorylation, there are two possible shuttles, the glycerol phosphate shuttle and the malate-aspartate shuttle. In comparing the two shuttles' e"ciency and the reason for the di!erence, we find that the glycerol phosphate shuttle is A) less e"cient, electrons pass into FADH2 B) less e"cient, electrons pass into NADH C) less e"cient, electrons pass into phosphate D) more e"cient, electrons pass into FADH2 E) more e"cient electrons pass into NADH F) more e"cient, electrons pass into phosphate

A

Which of the following compounds does NOT contribute carbon or nitrogen to the purine ring? A) Arginine B) Aspartate C) Formate D) Gluatmine E) Glycine

A

Which one of the following statements regarding glycogen metabolism is true? A) Glycogenin acts as a primer in the formation of glycogen molecule B) Glycogen synthase is active in the phosphorylated form C) Oligo alpha [1-4] -> alpha [1-4] glucan transferase is a branching enzyme in glycogenesis D) Insulin inhibits protein phosphatase and activate glycogenolysis E) Muscle glycogenolysis regulates the blood glucose level

A

: Release of acetylcholine at the neuromuscular junction is dependent upon the influx of which of the following ions to permit binding of synaptic vesicles to the pre-synaptic membrane? A) Chloride B) Calcium C) Sodium D) Potassium E) Magnesium

B

A 15-year-old girl was brought to the emergency department with a tear of the tendons in the first dorsal compartment of the wrist from a severe bite by a pit bull dog. The injured tendons in this compartment would include which of the following muscles? A) Extensor carpi radialis longus and brevis B) Abductor pollicis longus and extensor pollicis brevis C) Extensor digitorum D) Extensor indicis proprius E) Extensor carpi ulnaris

B

A 25-year-old male athlete is admitted to the emergency department after a bad landing in the pole vault. Radiographic examination of his hand reveals a fractured carpal bone in the floor of the anatomic snu!box (Fig. 6-1). Which bone has most likely been fractured? (Image on next page) A) Triquetral B) Scaphoid C) Capitate D) Hamate E) Trapezoid

B

A 27-year-old woman falls from her horse, sustaining a mid-shaft fracture of both her forearm bones. Her arm is placed in a cast for 6 weeks and after removal, she is referred for physical therapy. She is asked to open a lock with a key but experiences di"culty. Which of the following movements is responsible for opening and locking a lock? A) Flexion and extension of elbow B) Supination and pronation of forearm C) Flexion and extension of wrist D) Abduction and adduction of wrist E) Medial and lateral rotation of shoulder

B

A 42-year-old male is bitten superficially on his posterior thigh by a dog. The superficial wound is sutured in the emergency department. Four days later the patient returns to the hospital with high fever and swollen lymph nodes. Which group of nodes will first receive lymph from the infected wound? A) External iliac B) Vertical group of superficial inguinal C) Deep inguinal D) Horizontal group of superficial inguinal E) Internal iliac

B

A 54-year-old female marathon runner presents with pain in her right wrist that resulted when she fell with force on her outstretched hand. Radiographic studies indicate an anterior dislocation of a carpal bone (Fig. 6-3). Which of the following bones is most likely dislocated? A) Capitate B) Lunate C) Schphoid D) Trapezoid E) Triquetrum

B

A 72-year-old woman trips over the edge of the carpet and falls forward onto the floor. A common reflex reaction to ripping and falling forward is to extend ones hands to ease the impact of stoking the floor. She presents to the ER holding her left arm with her right hand. There is an obvious posterior displacement of the left distal wrist and hand that looks like a dinner fork. Which bone(s) is/are likely involved in a classic Colles fracture? A) Always the ulna and sometimes the radius B) Always the radius and sometimes the ulna C) Always the ulan and sometimes the scaphoid D) Always the radius and sometimes the trapezium E) Only the ulna

B

A patient was diagnosed with a deficiency of the lysosomal enzyme alpha-glycosidase. The name of the deficient enzyme suggests that it hydrolyzes a glycosidic bond, which is best described as a bond formed via which of the following? A) Through multiple hydrogen bonds between two sugar molecules B) Between the anomeric carbon of a sugar and an O—H (or N) of another molecule C) Between two anomeric carbons in polysaccharides D) Internal bond formation between the anomeric carbon of a monosaccharide and its own fifth carbon hydroxyl group E) Between the carbon containing the aldol or keto group and the alpha-carbon of the sugar

B

Adenosine deaminase deficiency leads to deficiency of all deoxyribose nucleotides because A) Adenine activates adenine phosphoribosyltransferase B) dATP accumulates and inhibits ribonucleotide reductase C) Guanase is also usually deficient D) Tetrahydrofolate is not properly cycled E) Xanthine oxidase is inhibited

B

An infant born to an alcoholic mother had microcephaly and cardiac abnormalities and died despite resuscitative e!orts. During which of the following periods of pregnancy is alcohol most teratogenic? A) First 2 weeks B) Third through ninth weeks C) Ninth through twelfth weeks D) Twelfth through sixteenth weeks E) Sixteenth through twentieth weeks

B

At the end of each phase of the cell cycle cyclins activating Cdks in that phase are inactivated irreversibly by which of the following mechanisms? A) Ubiquitinylation B) Destruction by proteolysis in a proteasome C) Dephosphorylation D) Multiple phosphorylations

B

In a presurgical patient, the great saphenous vein is cannulated in the vicinity of the ankle. During the procedure, the patient experiences severe pain that radiates along the medial border of the foot. Which one of the following nerves was accidentally included in a ligature during this procedure? A) Medial femoral cutaneous nerve B) Saphenous nerve C) Superficial fibular nerve D) Sural cutaneous nerve E) Tibial nerve

B

In the branched-chain metabolic pathway in which a di!erent single enzyme catalyzes each of the individual steps, the enzyme that would be expected to be most severely inhibited by compound V is enzyme A) A B) B C) C D) D E) E

B

Which of the following events does not occur during the first week of development? A) Blastocyst formation B) Implantation C) Gastrulation D) Cleavage of the zygote E) Fertilization

C

5-Fluorouracil inhibits DNA synthesis by decreasing the cell's supply of dTMP. This drug A) activates uridine phosphorylase B) activate uracil phosphoribosyl transferase C) inhibits ribonucleotide reductase D) inhibits thymidylate synthetase inhibits thymidinekinase

D

Which of the following best describes the typical site of implantation? A) Cervix B) Ovary C) Uterine tube D) Vagina E) Uterus

E

Which one of the following is correct about protein? A) Domain is a type of secondary structure B) Silk structure is an alpha helical fibrous structure C) Proline participates in hydrogen bond network D) Lysine residues will hydrogen bond with Arginine E) Lysine residues increase the protein solubility

E

A 25-year-old man, an intravenous drug abuser, had been injecting himself with temazepam (a powerful intermediate-acting drug in the same group as Valium) and heroin for 5 years, leaving much residual scar tissue over points of vascular access. The patient is admitted to the emergency department for a detoxification program requiring an intravenous infusion. The femoral veins in his groin are the only accessible and patent veins for intravenous use. Which of the following landmarks is the most reliable to identify the femoral veins? A) The femoral vein lies medial to the femoral artery B) The femoral vein lies within the femoral canal C) The femoral vein lies lateral to the femoral artery D) The femoral vein lies directly medial to the femoral nerve E) The femoral vein lies lateral to the femoral nerve

A

A 27-year-old man was admitted to the emergency department after an automobile collision in which he su!ered a fracture of the lateral border of the scapula. Six weeks after the accident, physical examination reveals weakness in medial rotation and adduction of the humerus. Which nerve was most likely injured? A) Lower subscapular B) Axillary C) Radial D) Spinal accessory E) Ulnar

A

A 34-year-old man is pushing some heavy weights while doing squats. Unfortunately, while maxing out, he drops the weight and immediately grabs at his upper thigh, writhing in pain. The man is admitted to the emergency department and during physical examination is diagnosed with a femoral hernia. What reference structure would be found immediately lateral to the herniated structures? A) Femoral vein B) Femoral artery C) Pectineus muscle D) Femoral nerve E) Adductor longus muscle

A

A 45-year-old man is admitted to the hospital after a car crash. Radiographic examination reveals mild disk herniations of C7, C8, and T1. The patient presents with a sensory deficit of the C8 and T1 spinal nerve dermatomes. The dorsal root ganglia of C8 and T1 would contain cell bodies of sensory fibers carried by which of the following nerves? A) Medial antebrachial cutaneous nerve B) Long thoracic nerve C) Lateral antebrachial cutaneous nerve D) Deep branch of ulnar nerve E) Anterior interosseous nerve

A

A clone of cells is grown on a tissue culture plate. It is known that the diploid amount of DNA in this species is 2 units. The amount of DNA measured in a cell sorter for fours cells from this culture is: Cell I - 2 Cell II - 2.5 Cell III - 4 Cell IV - 4 Cell I: A) has just completed telophase B) has just completed the S phase C) is in mitosis D) is in the same stage of the cell cycle as Cell II E) will incorporate tritiated thymidine into its nucleus

A

A 16-year-old gymnast presents to the emergency department after landing awkwardly on her ankle. She is diagnosed with a sprained ankle. Which of the following ligaments is most commonly injured in an ankle sprain? A) Anterior talofibular ligament B) Calcaneofibular ligament C) Talonavicular ligament D) Tibiocalcaneal ligament E) Tibiotalar ligament

A

A 21-year-old female softball pitcher is examined in the emergency department after she was struck in the arm by a line drive (a ball hit very hard and low). Radiographic and MRI studies show soft tissue injury to the region of the spiral groove, with trauma to the radial nerve. Which of the following muscles would be intact after this injury? A) Flexor carpi ulnaris B) Extensor indicis C) Brachioradialis D) Extensor carpi radialis E) Supinator

A

A 25-year-old butcher has had severe episodic pain in his right thumb and right second and third digits for 2 months. The pain frequently awakens him from sleep. He has decreased sensation over the palmar surface of the thumb and index and long fingers of the right hand and atrophy of the thenar muscle mass. Compression of which of the following nerves is the most likely cause? A) Median B) Musculocutaneous C) Posterior interosseous D) Radial E) Ulnar

A

Many metabolic reactions involve the transfer of electrons. Which of the following statements concerning electron transfer is TRUE? A) NADH reducing equivalents are used mainly in biosynthetic reactions. B) A flavoprotein is an intermediate electron transport chain carrier between NADH and ubiquinone. C) Both of the "high energy" phosphate linkages of ATP are added during oxidative phosphorylation. D) NADPH is used as the primary electron carrier in electron transport. E) Cyanide blocks the transfer of electrons from NADH to ubiquinone.

B

Select the correct statement regarding the structure of glycoproteins A) The length of the carbohydrate chain is longer than proteoglycans B) The glycoprotein carbohydrate chains are often branched C) They are mainly made up of repeating disaccharide units D) Oligosaccharide attached to the protein by hydrophobic bond E) Pentoses are the main carbohydrate units present in the structure

B

Some forms of Ehlers-Danlos syndrome are characterized by abnormally elastic skin. This is due to defective formation and function of A) Alpha 1 antitrypsin B) Collagen C) Elastin D) Elastase E) Fibrillin

B

Sphingomyelin is a phospholipid present mainly in the nervous tissue. Its synthesis requires A) Succinyl CoA B) Phosphatidylcholine C) NADH D) N-Acetylneuraminic acid E) Arachidonic acid

B

The graph illustrates the e!ects of tetraethylamonium (TEA) on the action potential of an axon. The most likely action of TEA is to A) open K+ gates, causing membrane permeability to K+ to increase during the action potential B) block K+ gates, preventing membrane permeability to K+ from increasing during the action potential C) open Na+ gates, causing membrane permeability to Na+ to increase D) block the Na+/K+ active pump during the action potential E) close Na+ gates, preventing membrane permeability to Na+ from increasing during the action potential

B

The regulation of translation in eukaryotes can be accomplished through reversible phosphorylation of A) EF-2 B) eIF-2 C) eRF-1 D) eRF-2 E) eIF-5

B

Which of the following best describes an attribute of visceral smooth muscle not shared by skeletal muscle? A) Contraction is ATP dependent B) Contracts in response to stretch C) Does not contain actin filaments D) High rate of cross-bridge cycling E) Low maximal force of contraction

B

Which of the following characterize alpha-helix regions of proteins? A) They all have the same primary structure B) They are formed principally by hydrogen bonds between a carbonyl oxygen atom in one peptide bond and the amide hydrogen from a di!erent peptide bond C) They are formed principally by hydrogen bonds between a carbonyl atom in one peptide bond and the hydrogen atoms on the side chain of another amino acid D) They are formed by hydrogen bonding between two adjacent amino acids in the primary sequence E) They require a high content of proline and glycine

B

Which of the following pairs of hormones and the corresponding action is incorrect? A) Glucagon—increased glycogenolysis in liver B) Glucagon—increased glycogenolysis in skeletal muscle C) Glucagon—increased gluconeogenesis D) Cortisol—increased gluconeogenesis E) Cortisol—decreased glucose uptake in muscle

B

Which of the following parts of bone develop from the primary ossification center? A) metaphysis B) diaphysis C) epiphysis D) epiphyseal plate

B

Your patient has presented with a mild megaloblastic anemia. Urinanalysis reveals the presence of orotic acid. Which one of the enzymes below is likely to be defective in this patient? A) Hypoxanthine phosphoribosyltransferase. B) Uridine monophosphate synthase. C) Phosphoribosylpyrophosphate amidotransferase. D) Aspartate transcarbamoylase. E) Carbamoyl phosphate synthetase I.

B

20-year-old medical student met an accident and su!ered from multiple injuries all over the body with the bone fracture. Your surgeon colleague prefers to supplement patients with ascorbic acid after surgery. The doctor trying to optimize which one of the following process? A) The formation of desmosine in collagen B) The formation of hydroxylysines in elastin C) The hydroxylation of proline in tropocollagen D) The cleavage of pro-peptides from pro-collagen E) The addition of galactose to lysine in elastin

C

A 13-year-old adolescent is brought to the family practice clinic by his mother, because he can barely walk. He has been trying out for a soccer team for the last 2 weeks. but in the last few days has developed right knee pain and swelling. Upon examination the pain is below the knee joint along the tibia where the patellar tendon attaches. What is the most likely source of the problem? A) Anterior cruciate ligament (ACL) strain B) Bursitis C) Osteochondritits of the tibial tubercle D) Prepatellar bursitis E) Quadriceps tendonitis

C

A 32-year-old man presents with abnormal phenotypic manifestation of Marfan syndrome, an autosomal dominant genetic disorder. With an una!ected female partner, what is the chance for him to have a normal child? A) 0% B) 25% C) 50% D) 75% E) 100%

C

A 60-year-old man has tenderness in the region distally between the tendons of the extensor pollicis longus and extensor pollicis brevis (anatomical snu!box) after falling on the palm of his right hand. A fracture of which of the following carpal bones is most likely in this patient? A) Hamate B) Lunate C) Scaphoid D) Trapezium E) Triquetrum

C

A baseball pitcher delivers 97-mph fastball to a batter and suddenly feels a sharp pain in his shoulder on release of the ball. The trainer examines the shoulder and concludes that the pitcher has a rotator cu! injury. Which of the following muscles i most vulnerable and most likely torn by this type of injury? A) Infraspinatus B) Subscapularis C) Supraspinatus D) Teres minor E) Teres major

C

Activin is a protein that normally exists in a gradient within certain tissues in developing embryos. Certain undi!erentiated cells cultured without activin produce epidermal cells. However, activin induces these same cells to adopt other fates (e.g., blood, muscle, heart), depending on the concentration of activin. Based on these observations, activin acts as a: A) transcription factor B) cell surface receptor C) morphogen D) second messenger E) activator

C

During gel electrophoresis, large DNA fragments will small DNA fragments. A) migrate more rapidly than B) migrate at the same speed as C) migrate more slowly than D) cause degradation of E) separate into

C

Glucokinase catalyzes the transfer of the γ - phosphate of ATP to glucose. What is the ΔG°` of the reaction if the ΔG°` of ATP hydrolysis is -30.5 kJ/mol, and the ΔG°` of adding phosphate to glucose is +14 kJ/mol A) +16.5 kJ/mol B) +44.5 kJ/mol C) -16.5 kJ/mol D) -44.5 kJ/mol E) Approximately 2 kJ/mol

C

If the cytosolic concentration of malonyl CoA decreases, which of the following will happen as a result of this change? A) activity of lipoprotein lipase decreases B) activity of lipoprotein lipase increases C) beta-oxidation of fatty acids increases D) fatty acid synthesis increases E) transport of fatty acids out of mitochondria increases F) transport of fatty acids out of mitochondria decreases

C

In your laboratory you are studying a particular mutation which is thought to occur in a region which is responsible for regulation of a specific gene's expression. You wish to examine the level of activity of the gene by detecting the product of the transcription process in cultured fibroblasts. The most common technique for making these measurements is A) enzyme-linked immunosorbent assay (ELISA) B) gas chromatography (GC) C) Northern blot D) polymerase chain reaction (PCR) E) Southern blot F) Western blot

C

Individual blastomeres were isolated from a blastula at the 4-cell stage. Each blastomere was cultured in vitro to the blastocyst stage and individually implanted into four pseudopregnant foster mothers. Which of the following would you expect to observe 9 months later? A) Birth of one baby B) Birth of four genetically di!erent babies C) Birth of four genetically identical babies D) Birth of four grotesquely deformed babies E) No births

C

Intermediate mesoderm will give rise to the A) neural tube B) heart C) kidneys and gonads D) somites E) notochord

C

Nicotinic receptors are mainly found in or on: A) Postganglionic sympathetic terminals B) Smooth muscle of hollow viscera C) Adrenal medulla D) Postganglionic parasympathetic terminals E) Sweat glands

C

Refer the reaction given below and respond to the statements Fructose-I-Phosphate --> Glyceraldehyde + Dihydroxyacetone Phosphate A) The product dihydrocyacetone phosphate is an aldose sugar B) The reaction is catalysed by aldolase A C) The deficiency of the enzyme system in the reaction causes to essential fructosuria D) The reaction bypasses the PFK-1 step of glycolysis E) Feeding more of fructose rich diet is the treatment for the clinical condition caused by the deficiency of the enzyme for the reaction

C

The force produced by a single skeletal muscle fiber can be increased by which of the following? A) Decreasing extracellular K+ concentration B) Increasing the amplitude of the depolarizing stimulus C) Increasing the frequency of stimulation of the fiber D) Increasing the number of voltage-gated Na+ channels in the sarcolemma E) Increasing the permeability of the sarcolemma to K+

C

The length-tension diagram shown here was obtained from a skeletal muscle with equal numbers of red and white fibers. Supramaximal tetanic stimuli were used to initiate an isometric contraction at each muscle length studied. The resting length was 20 cm. What is the maximum amount of active tension that the muscle is capable of generating at a preload of 100 gs? A) 145-155 grams B) 25-35 grams C) 55-65 grams D) 95-105 grams E) Cannot be determined

C

The sequence of amino acids at the amino terminal part of secretory proteins as first synthesized serves to A) enhance enzymatic activity B) protect against proteolytic digestion C) facilitate passage through membranes D) speed transport through the ducts of glands E) receive the addition of glucose in the Golgi complex

C

What is the principle method of inactivation of catecholamines released from nerve terminals in the CNS? A) Enzymatic hydrolysis B) Postsynaptic uptake C) Presynaptic reuptake D) Uptake by astrocytes E) Vascular washout for catabolism by the liver

C

Which of the following is a characteristic of globular proteins? A) Hydrophilic amino acids tend to be on the inside B) Hydrophobic amino acids tend to be on the outside C) Tertiary structure is formed by hydrophobic and electrostatic interactions between amino acid side chains and by hydrogen bonds between peptide bonds D) Secondary structures are formed principally hydrophobic interactions between amino acids E) Covalent disulfide bonds are necessary to hold the protein in a rigid conformation

C

Which of the following pairs of values will allow us to conclude that a reaction must be spontaneous? A) ΔG < 0 and exothermic B) ΔG = 0 and at equilibrium C) ΔG < 0 and exergonic D) ΔG < 0 and endergonic E) ΔG > 0 and exergonic

C

Which one of the following statement regarding the synthesis and function of nitric oxide is true? A) Its synthesis requires NADP+ B) It is synthesized from citrulline C) It helps in the relaxation of smooth muscle D) It is a powerful vasoconstrictor E) L-Alanine is the substrate for nitric oxide synthase

C

A 32-year-old pregnant woman with a history of deep venous thrombosis associated with oral contraceptive use is seen for her first prenatal visit. Her mother also had an episode of deep vein thrombosis during pregnancy. DNA from the woman is tested for a potential mutation in the factor V gene known to cause this condition. The DNA sequence to be amplified by PCR is shown below. The dashed line indicates the internal sequence where the potential mutation is located. Which answer choice represents the pair of primers that should be used in the PCR? TCCTGAGC —————— AAATGTGT A) AGGACTCG and TTTACACA B) GCTCAGGA and AAATGTGT C) GCTCAGGA and ACACATTT D) TCCTGAGC and ACACATTT E) TCCTGAGC and TTTACACA

D

A lethal mutation occurs in a bacterium, rendering it incapable of replicating its chromosome. Because of this mutation, DNA synthesis produces many short fragments of DNA that have RNA sequences at their 5' ends. The mutation is most likely in a gene encoding which of the following? A) DNA gyrase B) DNA helicase C) DNA ligase D) DNA polymerase I E) Primase

D

A screening study done on a couple indicates that the husband is a!ected with an autosomal recessive disease. Although his wife is una!ected, her (wife's) mother is found to be a!ected with the same genetic disease. The couple wants to know about their chance of having child with a mutant gene/s for this disease. What is the probability? A) 0% B) 25% C) 50% D) 100%

D

At an enzyme active site, the amino acid most likely to be a!ected by changes in pH between 5 and 7 is A) arginine B) asparagine C) glutamine D) histidine E) lysine

D

Calmodulin is most closely related, both structurally and functionally, to which of the following proteins? A) G-actin B) Myosin light chain C) Tropomyosin D) Troponin C

D

Concerning a 14 day old blastocyst, select the most appropriate structure in the accompanying diagram which is the chorion A)AB)BC)CD)DE)EF)FG)G

D

In order to determine the rate of DNA synthesis in various mammalian tissues, the administration of which of the following labeled substances would be most specific in labeling DNA? A) Adenosine B) Cytosine C) Guanosine D) Thymidine E) Uridine

D

PCR is used for A) digesting proteins B) digesting DNA C) copying plasmids D) amplifying DNA E) amplifying proteins

D

Replication of the genome occurs in the phase of the cell cycle A) G1 B) G) C) M D) S E) G2

D

The major source of ammonia excreted into the urine by the kidneys of most vertebrate animals is A) alanine B) asparagine C) glutamic acid D) glutamine E) glycine

D

The resting potential of a myelinated nerve fiber is primarily dependent on the concentration gradient of which of the following ions? A) Ca++ B) Cl- C) HCO3- D) K+ E) Na+

D

Which of the following best describes the long, cylindrical, main region of a long bone? A) Compact bone B) Epiphysis C) Metaphysis D) Diaphysis E) Spongy bone

D

Which of the following compounds is an allosteric activator of glycogen phosphorylase b in muscle? A) cAMP B) ATP C) Glucose D) AMP E) Glucose-6-Phosphate

D

Which of the following individuals developed the MOST WIDELY used cerebral cytoarchitectonic map? A) Rexed B) Broca C) Geschwind D) Brodmann E) Gall

D

A 25-year-old male medical student presents in the health clinic complaining of a painful, rigid muscle. Which of the conditions described in the table is most likely to be found in a rigid muscle? (Image on next page) A) Condition A B) Condition B C) Condition C D) Condition D E) Condition E

E

A 34-year-old woman presents to her physician complaining of oral ulcers. A careful history reveals that she is a strict vegetarian and does not eat meat, fish, poultry, eggs, or dairy products. She is found to have a severe riboflavin deficiency. The function of which of the following enzymes in the citric acid cycle would be most directly a!ected by the riboflavin deficiency? A) Aconitase B) Citrate synthase C) Isocitrate dehydrogenase D) Malate dehydrogenase E) Succinate dehydrogenase

E

A 35-year-old man attends your clinic for regular health checkup. He is sedentary in his habits, a non-smoker and is 2.0 m in height. He weighs 132 kg. Based on his BMI, he would be classified as A) borderline obese B) underweight C) overweight D) class III obese E) obese

E

A 36-year-old man is brought to the emergency department because of a deep knife wound on the me- dial side of his distal forearm. He is unable to hold a piece of paper between his fingers and has sensory loss on the medial side of his hand and little finger. Which nerve is most likely injured? A) Axillary B) Median C) Musculocutaneous D) Radial E) Ulnar

E

A 47-year-old female tennis professional is in- formed by her physician that she has a rotator cu! in- jury that will require surgery. Her physician explains that over the years of play a shoulder ligament has gradually caused severe damage to the underlying muscle. To which of the following ligaments is the physician most likely referring? A) Acromioclavicular ligament B) Coracohumeral ligament C) Transverse scapular ligament D) Glenohumeral ligament E) Coracoacromial ligament

E

A pathologist is examining microscope slides of a skin biopsy from a patient with malignant melanoma. The pathologist notes in the microscopic description of the report that almost all of the melanoma cells have very large, visible nucleoli. This finding specifically suggests that these cells are making large amounts of which of the following? A) Cell surface markers B) Golgi apparatus C) Immunoglobulins D) New DNA E) Ribosomes

E

An otherwise healthy infant boy born via vaginal delivery has an abnormal appearance of his right upper limb. His arm hangs by his side, pronated and medially rotated. Which of the following muscles is still functioning in this patient? A) Biceps B) Deltoid C) Infraspinatus D) Supraspinatus E) Triceps

E

Approximately how many sperm will be ejaculated by a normal fertile male during sexual intercourse? A) 10 million B) 20 million C) 35 million D) 100 million E) 350 million

E

Congenital absence of the parathyroids is most likely to be accompanied by absence or poor development of the A) lungs B) anterior portion of the pituitary gland C) thyroid gland D) nasopharyngeal portions of the eustachian tubes E) thymus

E

Constituents of normal plasma membrane include 1) phospholipids 2) proteins 3) glycolipids 4) cholesterol A) 1,2,3 only B) 1,3 only C) 2,4 only D) 4 only E) All are correct

E

Drugs that inhibit the action of DNA topoisomerase are e!ective agents for the treatment of viral infections and are used in anticancer therapy, because they directly inhibit A) A transient breakage and rejoining of N-glycosidic bonds in the double helix B) The formation of telomeres C) The initiation of replication D) The formation of replication fork E) The transient breakage and rejoining of phosphodiester bonds in the DNA double helix

E

Intramembranous ossification di!ers from endochondral ossification in which one of the following ways? A) Action of osteoblasts B) Light microscopic appearance of the adult bone C) Ultrastructural appearance of the adult bone D) Presence of woven bone early in the ossification process E) Microenvironment in which ossification occurs

E

N-terminal and C-terminal polypeptides of collagen are cleaved in A) Nucleus B) Rough endoplasmic reticulum C) Smooth endoplasmic reticulum D) Ribosomes E) Extracellular space

E

Synthesis of ATP in the mitochondria 1) involves expulsion of protons coupled to electron transport 2) is carried out by an ATPase specifically oriented in the membrane 3) is inhibited by antimycin 4) accounts for most of the O2 consumption in humans A) 1,2,3 only B) 1,3 only C) 2,4 only D) 4 only E) All are correct

E