PACAT Practice Exam - Version 1

Question 1

Imagine that you are walking through a park at night and all of a sudden you see something run across the path in front of you. Very quickly, you will notice your body preparing to either fight or run. In stressful situations, humans will often exhibit this fight-or-flight response. How does this response occur?

a. Release of the hormone epinephrine (adrenaline)

b. Release of the hormone insulin

c. Release of the neurotransmitter serotonin

d. Release of the neurotransmitter dopamine

Answer 1

a. Release of the hormone epinephrine (adrenaline)

Question 2

Case:
Somatic mosaicism is when an individual contains two distinct cell populations as a result of a postzygotic mutation, with phenotypic consequence partially influenced by the extent of chromosomal rearrangement.

Question:
Chromosomal rearrangement is implicated in what somatic change?

a. Germinal mutation

b. Malignancy

c. Meiotic segregation

d. Recombination

Answer 2

b. Malignancy

Question 3

Following an automobile accident, physical examination shows damage to a patient’s deltoid muscle and teres minor muscle. The patient is unable to abduct and laterally rotate their arm. What nerve is likely injured?

a. Axillary nerve

b. Musculocutaneous nerve

c. Radial nerve

d. Thoracodorsal nerve

Answer 3

a. Axillary nerve

Question 4

Case:
A patient presents after 24 hours of fasting.

Question:
What source are they using as a substrate for gluconeogenesis?

a. Amino acids

b. Even-chain fatty acids

c. Glucose

d. Glycogen

Answer 4

a. Amino acids

Question 5

A stats class consists of 20 girls and 24 boys. Of these, 15 boys and half of the mentioned girls study economics. If a person is chosen at random from the class, find the probability that the person selected is a girl who studies economics.

a. 5/22

b. 3/11

c. 15/44

d. 5/11

Answer 5

a. 5/22

Question 6

75% of the breast lymphatics drain directly into what nodes?

a. Axillary nodes

b. Internal thoracic nodes

c. Pectoral nodes

d. Supraclavicular nodes

Answer 6

c. Pectoral nodes

Question 6

Sodium (Na) loses its electron to become sodium ion (Na+). What kind of reaction is this?

a. Oxidation reaction

b. Reduction reaction

c. Redox reaction

d. Decomposition reaction

Answer 6

a. Oxidation reaction

Question 7

Non-coding RNA refers to RNA that is transcribed from DNA but is not translated into a protein. Non-coding RNA can have many functions, many of which involve transcription and translation regulation. What type of RNA is considered a coding RNA?

a. miRNA (micro RNA)

b. mRNA (messenger RNA)

c. piRNA (piwi-interacting RNA)

d. siRNA (small interfering RNA)

Answer 7

b. mRNA (messenger RNA)

Question 8

What kind of ions do nonmetals form?

a. Anions

b. Cations

c. Neutral

d. No ions

Answer 8

a. Anions

Question 9

In what part of the body is there a thickened layer of epidermis?

a. Lower back

b. Pinna of ears

c. Scalp

d. Soles of the feet

Answer 9

d. Soles of the feet

Question 10

You are presented with a female patient who shows a pervasive pattern of instability in interpersonal relationships, self-image, and emotions. This instability of self-image can result in feelings of emptiness and fears of abandonment. She is very impulsive, often showing feelings of anger, especially when criticized. She sometimes performs self-harm by cutting herself and threatens suicide. What disorder may she be exhibiting?

a. Borderline personality disorder

b. Narcissistic personality disorder

c. Paranoid personality disorder

d. Schizoid personality disorder

e. Antisocial personality disorder

Answer 10

a. Borderline personality disorder

Question 11

Which of the following tasks in Freud’s psychosexual stages is possibly underachieved if the person is characterized by sarcasm, overeating, and nail-biting?

a. Oral

b. Anal

c. Phallic

d. Genital

Answer 11

a. Oral

Question 12

Synonymous mutations are DNA mutations that do not change the amino acid inserted into the protein, but they can change the local structure of a protein and the global folding of the protein.

Which levels of protein structure can synonymous mutations alter?

a. Primary and secondary structure

b. Primary and tertiary structure

c. Primary, secondary, and tertiary structure

d. Secondary and tertiary structure

Answer 12

d. Secondary and tertiary structure

Question 13

Case:
A 65-year-old woman slips and falls on the bathroom floor. She has a posterior dislocation of the hip joint and a fracture of the neck of the femur.

Question:
If the acetabulum is fractured at its posterosuperior margin by dislocation of the hip joint, what bone could be involved?

a. Pubis

b. Ilium

c. Ischium

d. Sacrum

Answer 13

b. Ilium

Question 14

Case:
In cattle, the inherited lack of horns is called “polled” and is due to a single gene locus. A breeder has one line of cattle that are true-breeding for polled and one line of cattle that are true-breeding for non-polled.

Question:
How could the breeder determine if the polled allele is dominant or recessive?

a. Breed cattle from the two lines together; if all offspring display one trait, that trait is dominant.

b. Breed cattle from the two lines together; if 75% of offspring display one trait, that trait is dominant.

c. Determine how many breeds of cattle are polled and non-polled; whichever is more common is dominant.

d. Determine whether the trait is adaptive in the current environment; if it is beneficial, it is dominant.

Answer 14

a. Breed cattle from the two lines together; if all offspring display one trait, that trait is dominant.

Question 14

In the urea cycle, what does the synthesis of carbamoyl phosphate depend upon?

a. Aspartate

b. Ornithine

c. Argininosuccinate

d. N-Acetylglutamic acid

Answer 14

d. N-Acetylglutamic acid

Question 15

Free fatty acids are transported in the blood by binding to which of the following compounds?

a. Hemoglobin

b. Gamma globulins

c. Albumin

d. Platelets

Answer 15

c. Albumin

Question 16

Case:
A patient presents with increased thirst and blurred vision. Analysis of their blood sugar demonstrates hyperglycemia.

Question:
What phenomenon may be observed through analysis of the patient’s erythrocytes?

a. Crenation

b. Hematopoiesis

c. Lysis

d. Swelling

Answer 16

a. Crenation

Question 17

Which pairing of an intravenously administered fluid and its effect on both intravascular fluid volume (IV) and extracellular fluid volume (ECV) would be correct in a normal patient?
Tonicity is given relative to normal plasma. Assume a simple 2-compartment model (vascular space [blood/plasma] and extracellular fluid space).

a. Isotonic (normal) saline (NaCl)—increase in both IV and ECV

b. Hypertonic saline—decrease in IV, increase in ECV

c. Hypotonic saline—(slight) decrease in IV, decrease in ECV

d. Isotonic (normal) saline—increase in IV, no change in ECV

e. 5% glucose in free water—initial increase in vascular volume, decrease in ECV

Answer 17

d. Isotonic (normal) saline—increase in IV, no change in ECV

Question 18

What specialized quality of dermatophytes enables them to infect skin, hair, and nails under normal conditions?

a. Antibiotic resistance

b. Evasion of dendritic cells

c. Induction of desquamation

d. Metabolism of keratin

Answer 18

d. Metabolism of keratin

Question 18

Case:
After a hurricane left a pharmacists’s laboratory without power for several weeks, the local hospital’s urgent need to replenish medical supplies required the pharmacist to utilize historic techniques in order to identify several bottles of medicine that had lost their labels from the flooding. The pharmacist performed combustion analysis of the four samples but only trusted the carbon measurement that found the molecular formulas of all samples to contain four carbons. Realizing their fractional distillation equipment was perfectly intact, the pharmacist determined the boiling point of these compounds and purified them at the same time.

Question:
In what order were these compounds distilled off?

Acetic anhydride (ethanoic anhydride); 2-hydroxyethyl acetate (glycerol monoacetate); 1,4-butanediol; n-butanoic Acid (butyric acid)

a. 1,4-butanediol, Acetic anhydride (ethanoic anhydride), Butanoic Acid (butyric acid), 2-hydroxyethyl acetate (glycerol monoacetate)

b. 2-hydroxyethyl acetate (glycerol monoacetate), Acetic anhydride (ethanoic anhydride), 1,4-butanediol, Butanoic Acid (butyric acid)

c. Acetic anhydride (ethanoic anhydride), Butanoic Acid (butyric acid), 1,4-butanediol, 2-hydroxyethyl acetate (glycerol monoacetate)

d. Acetic anhydride (ethanoic anhydride), Butanoic Acid (butyric acid), 2-hydroxyethyl acetate (glycerol monoacetate), 1,4-butanediol

Answer 18

d. Acetic anhydride (ethanoic anhydride), Butanoic Acid (butyric acid), 2-hydroxyethyl acetate (glycerol monoacetate), 1,4-butanediol

Question 19

Case:
A young woman was asked to be a part of a psychological study at her college. The study claimed to “measure one’s IQ by testing one’s physical strength.” After reading the description of the study, she decided to opt out of the study.

Question:
Which answer would explain why the woman would have opted out of the study?

a. The study lacked face validity.

b. The study had a strong bias.

c. The study was not reliable.

d. The study lacked construct validity.

Answer 19

a. The study lacked face validity.

Question 20

Case:
A physician examines a patient with pain and paresthesia in the left leg. The distribution of the pain, running down the lateral aspect of the leg and the dorsal surface of the foot, suggests a herniated intervertebral disk. The physician links the distribution of symptoms with nerve L5.

Question:
Where has herniation occurred?

a. L3 to L4 intervertebral disk

b. L4 to L5 intervertebral disk

c. L5 to S1 intervertebral disk

d. L2 to L3 intervertebral disk

Answer 20

b. L4 to L5 intervertebral disk

Question 20

A steroid hormone bypasses the surface receptor of a cell to instead attach to a target within the cell.

What organic molecule is performing this action?

a. Carbohydrate

b. Lipid

c. Nucleic acid

d. Protein

Answer 20

b. Lipid

Question 21

For similar reactions at STP, where we can assume A (the pre-exponential factor in an Arrhenius equation) is the same, what has the greatest activation energy?

a. k = 0.001

b. k = 0.1

c. k = 1

d. k = 1000

Answer 21

a. k = 0.001

Question 21

Case:
Molecular phylogenetic examinations have revealed misconstruction of proposed relatedness between species of bacteria—for example, Rhodocyclus tenuis and Rubrivivax gelatinosus falling under the Rhodospirillum genus due to sharing a helical shape.

Question:
What factor is most helpful to assess their relation?

a. Biochemical capabilities

b. Genome

c. Morphology

d. Phenotype

Answer 21

b. Genome

Question 22

A 21-year-old female student does exceptionally well in her studies, has a healthy social life, and enjoys horseback riding on weekends; however, her roommate says that this student is obsessed with being tidy and that she will spend hours at a time cleaning their apartment. The student also feels that she constantly requires an excessive amount of control over the things that happen in her life; she often feels that there is no point in trying to do things unless she can do them perfectly.

According to Freud’s psychosexual stage theory of development, which of the following is most likely to be true?

a. She has experienced a fixation at the anal stage of development.

b. She has successfully resolved her Elektra complex.

c. She has experienced a fixation at the oral stage of development.

d. She is experiencing a conflict at the genital phase of development.

Answer 22

a. She has experienced a fixation at the anal stage of development.

Question 23

Case:
Blue cone monochromacy is a rare and severe form of X-linked recessive color vision deficiency resulting in reduced sharpness and inability to see most colors. It is a result of a loss in 2 opsin genes (OPN1LW and OPN1MW), both of which are located at chromosomal location Xq28.

A woman with normal color vision and a colorblind man gave birth to twins (one boy and one girl). It is known that the woman’s mother had blue cone monochromacy, but her father had normal color vision.

Question:
Assuming that there are no other rare genetic linkage-events, what are the chances of the baby boy and baby girl also being colorblind?

a. All boys from this couple will be colorblind.

b. All girls from this couple will have normal color vision.

c. Since the opsin genes are X-linked, all girls from this couple will be colorblind.

d. The twins each have a 50:50 chance each of being colorblind.

Answer 23

d. The twins each have a 50:50 chance each of being colorblind.

Question 23

Case:
A doctor is using their stethoscope to auscultate the heart of a patient. They hear the S1 heart sound occurring as the mitral and tricuspid valves close during systole, where vibrations result due to changes to structure and blood flow.

Question:
Which is the louder component of this sound?

a. Closing of the aortic valve

b. Closing of the mitral valve

c. Closing of the pulmonic valve

d. Closing of the tricuspid valve

Answer 23

b. Closing of the mitral valve

Question 24

What happens to the entropy of a liquid evaporating in an environment where the temperature increases from 25°C to 200°C?

a. Increases

b. Decreases

c. Increases, then decreases

d. Decreases, then increases

e. Stays the same

Answer 24

a. Increases

Question 25

Case:
G protein-coupled receptors (GPCRs) are an integral component of many transduction pathways from a cell surface to an intracellular target.

Question:
Obstruction caused by what molecule regulates GPCR signal transduction?

a. Arrestin

b. cAMP

c. Gα

d. Gβγ

Answer 25

a. Arrestin

Question 26

A weak acid is titrated with a 2.0 M solution of NaOH, producing the titration curve shown. What is the approximate pKa of the acid? Refer to the image.

a. 3.0

b. 3.9

c. 5.2

d. 6.5

e. 8.2

Answer 26

c. 5.2

Question 27

How many sites does a ribosome have for the binding of tRNA?

a. 2

b. 3

c. 4

d. 5

Answer 27

b. 3

Question 28

What are an organism’s observable characteristics?

a. Genotype

b. Phenotype

c. Monohybrids

d. Dihybrids

Answer 28

b. Phenotype

Question 29

What is the physical framework upon which genetic information is carried in the nucleus of cells?

a. Chromosome

b. Gene

c. Genetic code

d. Genome

Answer 29

a. Chromosome

Question 29

Case:
Staphylococcus epidermidis is part of the normal microbiota and can act as an opportunistic pathogen. S. epidermidis is a key pathogen in catheter-related bloodstream infections, early-onset neonatal sepsis, and biomedical device-related infections.

Question:
Based on these characteristics, how else is S. epidermidis likely to be colonized?

a. Foodborne infection

b. Nosocomial infection

c. Vector-borne infection

d. Zoonotic infection

Answer 29

b. Nosocomial infection

Question 30

Which process releases energy from the sun?

a. Nuclear fission

b. Nuclear fusion

c. Photosynthesis

d. Evaporation

Answer 30

b. Nuclear fusion

Question 31

Case:
An excitable cell is hyperpolarizing to approach a value of -80 to -90 mV.

Question:
What phenomenon after this event represents the point when the efflux of potassium diminishes?

a. Action potential

b. Equilibrium potential

c. Membrane potential

d. Resting potential

Answer 31

b. Equilibrium potential

Question 32

Case:
A 70-year-old man has an abnormally increased curvature of the thoracic vertebral column.

Question:
What is the most likely diagnosis?

a. Kyphosis

b. Lordosis

c. Meningomyelocele

d. Spina bifida occulta

Answer 32

a. Kyphosis

Question 33

Case:
A 50-year-old man has difficulty breathing. He reports tiring more easily with exercise. Physical exam is remarkable for a systolic ejection click heard at the apex and at the upper right sternal border. He is referred to a cardiologist for further evaluation.

Question:
Which cardiac valve is causing these symptoms?

a. Aortic valve

b. Mitral valve

c. Pulmonic valve

d. Tricuspid valve

Answer 33

a. Aortic valve

Question 34

Case:
A person is breathing under normal physiological conditions. A negative pressure in the pleural cavity is created during inspiration.

Question:
What creates this pressure?

a. Diaphragm

b. Internal intercostals

c. Rectus abdominis

d. Sternocleidomastoid

Answer 34

a. Diaphragm

Question 35

Case:
Blood traveling through the normal pathway for systemic circulation has just left the left ventricle.

Question:
Where will the blood go next?

a. Pulmonary artery

b. Inferior vena cava

c. Aorta

d. Pulmonary vein

Answer 35

c. Aorta

Question 36

What is the difference between the social learning perspective and the sociocultural perspective?

a. Learning versus imitation

b. Learning versus pretending to learn

c. They are the same perspective, just named differently.

d. Learning from others outside immediate family versus learning from those inside immediate family

Answer 36

a. Learning versus imitation

Question 36

Case:
50 medical students were asked to complete a survey about the expected length of their desired residency program, graphed in blue. 50 graduating medical students were asked the same question about their confirmed future residency programs, graphed in red. Refer to the image.

Question:
What is the range of the larger cluster?

a. 3 to 6

b. 3 to 6.5

c. 3 to 7

d. 3 to 7.5

Answer 36

c. 3 to 7

Question 37

Select the strongest base. Refer to the image.

a. 4-Bromoaniline

b. 4-Methylaniline

c. 4-Methoxyaniline

d. 4-Acetylaniline

e. 4-Nitroaniline

Answer 37

c. 4-Methoxyaniline

Question 38

Which best describes the function of the scrotum?

a. Contains cells that produce testosterone

b. Contains Leydig cells

c. Includes the corpus cavernosa and the corpus spongiosum

d. Promotes production and viability of sperm

Answer 38

d. Promotes production and viability of sperm

Question 39

When referencing the elbow, what directional term describes the wrist relative to the fingers?

a. Caudal

b. Distal

c. Proximal

d. Superior

Answer 39

c. Proximal

Question 40

What is produced by cellular respiration in erythrocytes?

a. Citrate

b. Fumarate

c. Pyruvate

d. Succinate

Answer 40

c. Pyruvate

Question 41

Case:
A patient presents with vomiting and profuse, watery diarrhea 3.5 hours after eating chicken fried rice.

Question:
What is the most likely etiological agent?

a. Bacillus cereus

b. Clostridioides difficile

c. Escherichia coli

d. Listeria monocytogenes

Answer 41

a. Bacillus cereus

Question 41

What is the longest muscle in the body?

a. Biceps femoris

b. Gracilis

c. Quadriceps femoris

d. Sartorius

Answer 41

d. Sartorius

Question 42

In pea plants, tall (T) is dominant over short (t), and purple flowers (P) are dominant to white flowers (p). Given 2 parent plants that are heterozygous for both of these traits, what is the probability of producing tall offspring with white flowers?

a. 9/16

b. 3/16

c. 1/16

d. 0

Answer 42

b. 3/16

Question 43

What physical entity encodes all necessary information required for the maintenance and replication of an organism?

a. Allosome

b. Gene

c. Genetic code

d. Genome

Answer 43

d. Genome

Question 44

Environmental changes and nutrient availability impose a dynamic regulation of cellular metabolism. Which of the following are considered indicators for a cellular metabolic state? Select all that apply.

a. Glucose

b. AMP

c. Acetyl-CoA

d. NAD+

Answer 44

b. AMP

c. Acetyl-CoA

d. NAD+

Question 45

Case:
Patients with the genetic disorder Duchenne muscular dystrophy experience progressive muscle wasting that leads to progressive loss of ambulation, respiratory failure, and ultimately death. Laboratory studies reveal elevated serum levels of the enzyme creatine kinase. It is inherited in an X-linked recessive pattern, with the affected gene being one that encodes for the protein dystrophin. Unfortunately, life expectancy is rarely beyond age 30.

Question:
What statement correctly describes this disorder?

a. Both parents must be affected to pass the disorder on to their offspring.

b. Expression in males is affected by lyonization.

c. It affects mostly females.

d. It affects mostly males.

Answer 45

d. It affects mostly males.

Question 46

Case:
A 30-year-old man reports weakness when he extends his thigh and rotates it laterally.

Question:
What muscle is paralyzed?

a. Gluteus maximus

b. Obturator externus

c. Semitendinosus

d. Tensor fasciae latae

Answer 46

a. Gluteus maximus

Question 46

A patient presents with icterus. What is most likely affected from this state?

a. Iris

b. Pupils

c. Sclera

d. Conjunctiva

Answer 46

c. Sclera

Question 47

If a patient is standing in the correct anatomical position, where will their thumbs be relative to the rest of the body?

a. Deep

b. Lateral

c. Medial

d. Superficial

Answer 47

b. Lateral

Question 48

Case:
A researcher is conducting a survey and corresponding health evaluations, curious about the relationship between “happiness in life and career” and “blood pressure and heart disease.” They have a specific interest in the effects of an unhappy career on blood pressure and heart disease.

Question:
What type of study is this?

a. Double-blind experimental

b. Experimental-based observational

c. Single-blind experimental

d. Survey-based observational

Answer 48

d. Survey-based observational

Question 49

Case:
A 62-year-old man presents with bilateral pitting edema. He reports poor compliance with his medication regimen, and he has missed his last two appointments with his nephrologist.

Question:
When compared to arteries, what characteristic of veins predisposes this man to pitting edema?

a. Absence of valves

b. Smaller diameter

c. Smaller lumina

d. Thinner walls

Answer 49

d. Thinner walls

Question 50

Which of the following reactions produces heat and light?

a. Combustion

b. Endothermic

c. Exothermic

d. Photosynthesis

Answer 50

a. Combustion

Question 50

Case:
A 10-year-old patient presents with vomiting and confusion after drinking an excess of water. The patient is diagnosed with hyponatremia.

Question:
What phenomenon may be displayed through analysis of the patient’s cells?

a. Aggregation

b. Crenation

c. Hematopoiesis

d. Swelling

Answer 50

d. Swelling

Question 51

How does exhalation contribute to increasing the pressure in the venous system?

a. Blood flows from the thoracic region into veins outside the thorax.

b. Decreased pressure in the thoracic cavity decreases thoracic vein pressure.

c. Increased pressure in thoracic veins increases the flow of blood into the heart.

d. Increased thoracic volume causes increased blood pressure in the thoracic veins.

Answer 51

c. Increased pressure in thoracic veins increases the flow of blood into the heart.

Question 52

Case:
Peptidoglycan and other polymers and proteins are necessary for the survival of bacterial cells because they compose the cell wall. Enzymes active in forming the cell wall are targets for antibiotics.

Question:
What molecule is an appropriate target for antibiotics?

a. Catalase

b. Penicillin-binding protein

c. Pilin protein

d. Transferase

Answer 52

b. Penicillin-binding protein

Question 53

The term “heterozygote advantage” describes the case in which the heterozygous genotype of individuals within a population confers a higher relative fitness than either the homozygous dominant or homozygous recessive genotype. Which of the following is an example of a condition in which the heterozygote genotype confers a higher relative fitness?

a. Huntington’s disease

b. Tay-Sachs disease

c. Marfan syndrome

d. Cystic fibrosis

Answer 53

d. Cystic fibrosis

Question 54

Case:
HIV is a virus that causes disease and impacts evolution by moving large gene segments between organisms.

Question:
How does this behavior define HIV as a pathogen?

a. Phage

b. Prion

c. Retrovirus

d. Viroid

Answer 54

c. Retrovirus

Question 55

Case:
GAS5 is a long non-coding RNA associated with tumor suppression in multiple types of cancer. One hypothesis for how GAS5 exerts its effects is that it must fold into a hairpin structure to interact with the glucocorticoid receptor.

Question:
What bases would need to hydrogen bond with each other to form such a hairpin structure?

a. Adenine bonds with thymine; guanine bonds with cytosine.

b. Adenine bonds with thymine; guanine bonds with uracil.

c. Adenine bonds with uracil; guanine bonds with cytosine.

d. Adenine bonds with uracil; guanine bonds with thymine.

Answer 55

c. Adenine bonds with uracil; guanine bonds with cytosine.

Question 56

Case:
A patient presents with blurry vision and foreign body sensation following eye trauma when clearing yard debris. The patient was subsequently diagnosed with keratitis.

Question:
What is the most likely etiology?

a. Aspergillus

b. Campylobacter

c. Dermatophytes

d. Varicella-zoster

Answer 56

a. Aspergillus

Question 57

Case:
A person with an unknown blood type received an emergency transfusion with type O Rhesus D positive blood. They developed a delayed hemolytic transfusion reaction.

Question:
What component of the patient’s serum was most likely responsible for this reaction?

a. Anti-A antibodies

b. Anti-B antibodies

c. Anti-C antibodies

d. Anti-D antibodies

Answer 57

d. Anti-D antibodies

Question 57

Which of the following monosaccharides do not share the general formula of carbohydrates: H–(CHOH)x(C=O)–(CHOH)y–H?

a. Glucose

b. Fructose

c. Glyceraldehyde

d. Fucose

Answer 57

d. Fucose

Question 58

Case:
Neisseria meningitidis colonizes the nasopharynx but can become invasive. One mechanism that increases virulence is based on inhibition of phagocytosis in the bloodstream and central nervous system.

Question:
Which is responsible for this mechanism?

a. Antigenic variation

b. Pili

c. Polysaccharide capsule

d. Porin proteins

Answer 58

c. Polysaccharide capsule

Question 58

Case:
Staphylococcus aureus, a significant pathogen in skin and soft tissue infections, can cause dermonecrosis. Pathogenesis occurs in a bimodal fashion as the secreted toxins cause skin damage.

Question:
What additional mechanism of virulence is caused by secreted toxins?

a. Competition for iron

b. Greater adherence factors

c. Immune evasion

d. Increased invasion ability

Answer 58

c. Immune evasion

Question 59

A nurse has been given a pure solid form of calcium carbonate (CaCO3) and is asked to prepare a lime (CaO) mixture from it. What is the percentage loss in weight after heating a pure sample of calcium carbonate? The molecular weight of calcium (CaCO3) is 100 g/mol.

a. 0.44%

b. 13.5%

c. 44%

d. 56%

Answer 59

c. 44%

Question 59

Case:
A doctor is using their stethoscope to auscultate the heart of a patient. They hear the S2 heart sound occurring as the aortic and pulmonic valves close during diastole, where the closure of each valve is discernible due to a pressure difference.

Question:
Which is the louder component of this sound?

a. Closing of the aortic valve

b. Closing of the mitral valve

c. Closing of the pulmonic valve

d. Closing of the tricuspid valve

Answer 59

a. Closing of the aortic valve

Question 60

Case:
The bones that attach each upper limb to the axial skeleton form the pectoral girdle.

Question:
What attaches to the manubrium of the axial skeleton?

a. Acromial end of the clavicle

b. Inferior angle of the scapula

c. Shaft of the clavicle

d. Sternal end of the clavicle

Answer 60

d. Sternal end of the clavicle

Question 60

Case:
A researcher is conducting a survey and corresponding health evaluations, curious about the relationship between “happiness in life and career” and “blood pressure and heart disease.” They have a specific interest in the effects of an unhappy career on blood pressure and heart disease.

Question:
What is the population the researcher wants to observe, not including the normal?

a. All people

b. All people with heart problems

c. All people with heart problems and unhappy careers

d. All people with unhappy careers

Answer 60

d. All people with unhappy careers

Question 61

Which of the following is a glycoprotein that controls free iron in body fluids and binds with iron in plasma?

a. Siderophore

b. Ferritin

c. Transferrin

d. Hemoglobin

Answer 61

c. Transferrin

Question 62

Case:
A 29-year-old woman is going to have her first child. At the beginning of her third trimester, she takes birthing classes teaching how to do Kegel exercises.

Question:
What group of muscles will she be exercising?

a. Ischiocavernous muscles

b. Piriformis and obturator internus muscles

c. Piriformis, pubococcygeus, and iliococcygeus muscles

d. Puborectalis, pubococcygeus, and iliococcygeus muscles

Answer 62

d. Puborectalis, pubococcygeus, and iliococcygeus muscles

Question 63

Which of the following represents the atomic mass of an atom?

a. Number of protons in an atom

b. Number of electrons in an atom

c. Number of electrons and neutrons in an atom

d. Number of protons and neutrons in an atom

Answer 63

d. Number of protons and neutrons in an atom

Question 64

Case:
Air is flowing into the airways and alveoli, increasing the volume of the lungs.

Question:
Displacement of the central tendon of what muscle results in this action?

a. Abdomen

b. Diaphragm

c. Intercostals

d. Scalenes

Answer 64

b. Diaphragm

Question 64

You are in a lecture and your head begins to nod, but when your friend gently taps you, you are easily awoken. Which stage of sleep are you experiencing?

a. Stage 1 (introduction to sleep)

b. Stage 2 (beginning of sleep)

c. Stage 3 (slow wave sleep)

d. Stage 5 (REM)

Answer 64

a. Stage 1 (introduction to sleep)

Question 65

What is the chemical name of the following structure? Refer to the image.

a. 1,3-methylcyclopentane

b. 1,3-dimethylcyclopentane

c. 1,4-dimethylcyclopentane

d. 2,5-dimethylcyclopentane

Answer 65

b. 1,3-dimethylcyclopentane

Question 65

How many pi bonds are there in the following compound?

H - C ≡ C - CH2 - NO2

a. 1

b. 2

c. 3

d. 4

Answer 65

c. 3

Question 65

Two genetically identical plants are heterozygous for flower color. Which of the following describes the possible flower color genotypes of the offspring from these plants?

a. Homozygous and heterozygous

b. Only homozygous

c. Only heterozygous

d. Not enough information

Answer 65

a. Homozygous and heterozygous

Question 66

Frank went bungee jumping yesterday. According to arousal theory, what activity would Frank most likely do next and why?

a. Skydiving; Frank enjoys that level of activity.

b. Skydiving; Frank is feeling invincible.

c. Biking; Frank enjoys being outdoors.

d. Sleeping; Frank has used all of his energy.

Answer 66

a. Skydiving; Frank enjoys that level of activity.

Question 67

Case:
The release of GTP from a protein factor during the early stages of protein synthesis drives the assembly of the two ribosomal subunits, which otherwise exist freely.

Question:
What process results in the assembly?

a. Elongation

b. Initiation

c. Termination

d. Transcription

Answer 67

b. Initiation

Question 67

What does a pressure cooker do?

a. It increases the pressure inside the cooker, which decreases the temperature at which water boils.

b. Cooler liquid water inside the pressure cooker allows food to cook more quickly.

c. It increases the pressure inside the cooker, which increases the temperature at which water boils.

Answer 67

c. It increases the pressure inside the cooker, which increases the temperature at which water boils.

Question 68

Albinism is inherited in an autosomal recessive fashion (aa). Two parents who are carriers of the recessive trait (Aa) have four children, all of whom are homozygous recessive and express the albinism trait (aa). Using the Law of Segregation, if these parents were to have more children, what would their genotypic and phenotypic ratios be?

a. Genotypic ratio 1AA : 1Aa : 2aa
Phenotypic ratio 2 normal : 2 albinism

b. Genotypic ratio 1AA : 2Aa : 1aa
Phenotypic ratio 2 normal : 2 albinism

c. Genotypic ratio 1AA : 2Aa : 1aa
Phenotypic ratio 3 normal : 1 albinism

d. Genotypic ratio 2AA : 1Aa : 1aa
Phenotypic ratio 3 normal : 1 albinism

e. Genotypic ratio 3Aa : 1aa
Phenotypic ratio 3 normal : 1 albinism

Answer 68

c. Genotypic ratio 1AA : 2Aa : 1aa
Phenotypic ratio 3 normal : 1 albinism

Question 69

Case:
Paramecium cells display hydrodynamic cooperation of cilia when exposed to a shared fluid environment.

Question:
What intracellular constraint hinders this process?

a. Defined basal body placement

b. Fluid cytoskeletal architecture

c. Hydrodynamic stresses

d. Proximity of neighboring cilia

Answer 69

a. Defined basal body placement

Question 70

Case:
Pili and fimbriae are non-flagellar polymers that facilitate interaction between a bacteria and the external environment.

Question:
Where are these proteinaceous appendages displayed?

a. Cell surface

b. Mitochondrial surface

c. Nuclear surface

d. Ribosomal surface

Answer 70

a. Cell surface

Question 71

A 4 M KCl solution is diluted to create a 0.8 M KCl solution.

If the volume of the 0.8 M of KCl solution is 0.4 liters, what volume (in mL) of the 4 M KCl solution was used to make this diluted solution?

a. 0.08 mL

b. 2 mL

c. 80 mL

d. 2000 mL

Answer 71

c. 80 mL

Question 71

A child has to make a project about the Middle Ages for school. The child’s engineer father uses his knowledge to help the child build a small functional catapult.

Robert Sternberg describes three types of intelligence. Which type is the father displaying?

a. Creative

b. Analytical

c. Practical

d. Crystallized

e. Fluid

Answer 71

a. Creative

Question 72

Case:
In the autoionization of water, water reacts with itself functioning both as an acid and a base, and a certain molecule is produced. This molecule, which can donate three hydrogen bonds, can influence nearly 100 surrounding water molecules and can even form chains.

Question:
What molecule can perform these actions?

a. H2O

b. H3O+

c. H9O4+

d. OH-

Answer 72

b. H3O+

Question 72

What taste is NOT considered a basic form of gustatory sensation?

a. Sour

b. Bitter

c. Salty

d. Spicy

Answer 72

d. Spicy

Question 73

Case:
A newly synthesized RNA is on its way from the nucleus to the ribosome.

Question:
What must occur for eukaryotes to protect the RNA?

a. 3’ capping by 7-methylguanosine

b. 5’ polyadenylation

c. Addition of poly-A-tail on the 3’ end

d. Obstruction of splicing of the 5’ end

Answer 73

c. Addition of poly-A-tail on the 3’ end

Question 73

You are caring for an infant with abnormally wide suture lines. What health condition does the infant most likely have?

a. Elevated intracranial pressure

b. Hydrocephalus

c. Severe dehydration

d. Subarachnoid hemorrhage

Answer 73

b. Hydrocephalus

Question 74

Case:
A student wants to study breast cancer rates in women in a single city in the United States. The student asks women ages 20-100 in their samples.

Question:
What is the least biased sample of the population?

a. Members of a local Breast Cancer Awareness group

b. Members of a local family

c. Members of a local library

d. Members of a local neighborhood

Answer 74

c. Members of a local library

Question 75

Regarding the differences between sensation and perception, which of the following statements is most accurate?

a. Sensation involves the stimulation of one’s sensory organs; perception involves producing a mental representation of the world around us.

b. Sensation involves producing a mental representation of the world around us; perception involves processes such as sight, hearing, and touch.

c. Sensation and perception are largely interchangeable terms that refer to a singular process: that of experiencing the world around us.

d. Sensation and perception are separable but interconnected processes that are dependent upon one another.

Answer 75

a. Sensation involves the stimulation of one’s sensory organs; perception involves producing a mental representation of the world around us.

Question 76

Why is the pH of pure water neutral?

a. Water is never ionized.

b. Water has a greater concentration of H+ ions than H- ions.

c. Water has a greater concentration of OH- ions than H+ ions.

d. Water has the same concentration of OH- ions as H+ ions.

Answer 76

d. Water has the same concentration of OH- ions as H+ ions.

Question 76

Case:
During translation, a molecule is attached to amino acids through a reaction catalyzed by amino acid-specific synthetases.

Question:
What biological molecule is attached?

a. DNA

b. Protein

c. rRNA

d. tRNA

Answer 76

d. tRNA

Question 77

A man has a mutation that causes brain cells to grow larger than normal. If this mutation is to be passed on to his offspring, where must the mutation have happened?

a. A brain cell

b. A germline cell

c. Any cell in the body

d. Any cell in the reproductive system

Answer 77

b. A germline cell

Question 78

a. Zn(s) + 2OH−(aq) + 2 MnO2(s) + H2O(l) → Zn(OH)42−(aq) + Mn2O3(s)

b. Zn(s) + 2 MnO2(s) → ZnO(s) + Mn2O3(s)

c. MnO2(s) + 4 H+(aq) + Zn(s) → Mn2+(aq) + Zn2+(aq) + 2 H2O(l)

d. 2 MnO2(s) + 3 ZnO(s) + OH−(aq) → 3 Zn(s) + 2 MnO4−(aq) + H2O(l)

e. 2 MnO2(s) + H2O(l) + Zn(s) → Zn2+(aq) + Mn2O3(s) + 2 OH−(aq)

Answer 78

b. Zn(s) + 2 MnO2(s) → ZnO(s) + Mn2O3(s)

Question 79

A patient presents with a characteristic claw hand. Damage to what structure would lead to this sign?

a. Axillary nerve

b. Musculocutaneous nerve

c. Phrenic nerve

d. Ulnar nerve

Answer 79

d. Ulnar nerve

Question 80

Case:
An elderly woman presents with stiff neck, fever, and headache. Spinal fluid analysis confirms bacterial meningitis. Virulence factors of the responsible pathogen include intracellular mobility through actin polymerization and replication at refrigerator temperatures.

Question:
What would show on a Gram stain of this bacteria?

a. Gram-negative cocci

b. Gram-negative rods

c. Gram-positive cocci

d. Gram-positive rods

Answer 80

d. Gram-positive rods

Question 81

Case:
A patient undergoes the careful dissection of the anterior cervical neck due to advanced squamous cell carcinoma of the tongue with local invasion. The surgeon samples submandibular lymph nodes and resects a portion of the submandibular gland to do so. The patient tolerates the operation well and is taken to the ICU following the surgery due to the proximity of the surgery to the vocal cords and concern for edema. The patient is extubated on postoperative day 2 without difficulty, but their speech is dysarthric. The nurse calls the resident to bedside to evaluate for a possible stroke. The neurological exam is normal with the exception of tongue protrusion, which deviates to the left side.

Question:
What vessel courses through the submandibular space in proximity to the injured nerve?

a. Anterior jugular vein

b. Carotid artery

c. Facial artery

d. Mandibular artery

Answer 81

c. Facial artery

Question 82

A fly with large wings has 2 identical alleles for wing size. Another fly with small wings also has 2 identical alleles for wing size. When the flies are crossed, all of the resulting offspring have small wings. What does this imply about the alleles for wing size?

a. The large wing allele is dominant.

b. The small wing allele is dominant.

c. The alleles are codominant.

d. The small wing allele is homozygous.

e. The large wing allele is heterozygous.

Answer 82

b. The small wing allele is dominant.

Question 83

Case:
The plasma membrane of an excitable cell approaches its resting potential with a value between -80 and -70 mV.

Question:
What ion demonstrates the largest influence on the resting membrane potential at this point?

a. Calcium

b. Chloride

c. Potassium

d. Sodium

Answer 83

c. Potassium

Question 84

Case:
A 6-month old boy is brought in by his mother for a 6-month well baby check. The mother’s only concern is the patient’s neck motion and posture. She reports that over the last several months his head tilts toward the left and he never seems to straighten his head. She has also noticed that he has not been moving his neck to look at his surroundings. She notes otherwise he has been developing well, rolling over from front to back and back to front. He is able to sit up, is eating baby food, and is babbling as expected.

Question:
What is the likely neck structure causing the lateral head tilting and decreased range of motion?

a. Longus capitis

b. Platysma

c. Scalenes

d. Sternocleidomastoid

Answer 84

d. Sternocleidomastoid

Question 84

Saltatory conduction is the propagation of action potential across myelinated axons from which of the following?

a. One neurotransmitter to another

b. One muscle membrane to another

c. One node of Ranvier to another

d. One synapse to another

Answer 84

c. One node of Ranvier to another

Question 85

Case:
The carboxyl group of a fatty acid is being bound to the sulfhydryl group of coenzyme A.

Question:
Where does this reaction occur?

a. Endoplasmic reticulum

b. Golgi apparatus

c. Mitochondria

d. Lysosome

Answer 85

c. Mitochondria

Question 86

Which of the following statements accurately describes the chemical role that stress can play in hair turning gray?

a. Chronic stress weakens the hair follicles, causing them to be more susceptible to changing environments, which turns them gray.

b. Chronic stress can damage the cells (DNA) responsible for hair color, causing them to go gray.

c. Chronic stress does not affect hair color.

d. Chronic stress sends signals to the brain to stop producing hair and killing all viable hairs, turning them gray.

Answer 86

b. Chronic stress can damage the cells (DNA) responsible for hair color, causing them to go gray.

Question 87

Case:
Bacillus anthracis can be engulfed by macrophages within the alveoli, which facilitates transportation to lymph nodes. The bacteria multiply and begin toxin production.

Question:
What route of infection is implicated in this pathophysiology?

a. Cutaneous inoculation

b. Ingestion of contaminated meat

c. Injection by drug users

d. Spore inhalation

Answer 87

d. Spore inhalation

Question 88

Case:
A structure 3 m in length that ends at the cecum receives blood supplied by the superior mesenteric artery.

Question:
What is the major absorptive product of this structure?

a. Amino acids

b. B12

c. Fatty acids

d. Sugars

Answer 88

b. B12

Question 89

Case:
In general, ions and small molecules can passively diffuse through liquids. In water, however, certain molecules can diffuse 2-7 times more rapidly than others. Rapid diffusion of specific molecules in water enables water to play a crucial role in biological processes such as proton transfer in enzymes and biological channels.

Question:
What molecules participate in this process based on these characteristics?

a. Fatty acids and proteins

b. Lipids and sodium ions

c. Proteins and chloride ions

d. Protons and hydroxide ions

Answer 89

d. Protons and hydroxide ions

Question 90

Case:
An anaerobic process converts a starting molecule to lactate and results in the formation of two molecules of adenosine triphosphate (ATP) per starting molecule.

Question:
What is the starting molecule for this chemical reaction?

a. Cellulose

b. Glucose

c. Glycogen

d. Starch

Answer 90

b. Glucose

Question 91

Case:
An 80-year-old man presents with fever, chills, myalgia, confusion, and drowsiness following return from travel to Colorado. PCR reveals presence of Alphavirus.

Question:
What route of transmission did this infection most likely use?

a. Arthropod

b. Contaminated water

c. IV drug use

d. Sexual intercourse

Answer 91

a. Arthropod

Question 92

Case:
Aqueous sodium phosphate is mixed with aqueous calcium chloride by a bench scientist. Sodium chloride and calcium phosphate are produced in a precipitation reaction.

Question:
What is the representative chemical equation in net ionic format?

a. Na3PO4 (aq) + CaCl2 (aq) → NaCl (aq) + Ca3(PO4)2 (s)

b. 2Na3PO4 (aq) + 3CaCl2 (aq) → 6NaCl (aq) + Ca3(PO4)2 (s)

c. 6Na+(aq) + 2PO43- (aq) + 3Ca2+ (aq) +6Cl- (aq) → 6Na+ (aq) + 6Cl- (aq) +Ca3(PO4)2 (s)

d. 2PO43- (aq) + 3Ca2+ (aq) → Ca3(PO4)2 (s)

Answer 92

d. 2PO43- (aq) + 3Ca2+ (aq) → Ca3(PO4)2 (s)

Question 93

Case:
The histogram entitled “Netbook Laptop Prices Under $500” shows the distribution of prices for a sample of 50 netbook laptops available from a major online retailer when the search results are limited to a maximum price of $500.

Question:
Based on this histogram, what is an accurate description of the sample distribution? Refer to the image.

a. The sample distribution is skewed left and the median netbook laptop price is between $325 and $375.

b. The sample distribution is skewed right and the median netbook laptop price is between $325 and $375.

c. The sample distribution is skewed left and the median netbook laptop price is between $375 and $425.

d. The sample distribution is skewed right and the median netbook laptop price is between $375 and $425.

Answer 93

a. The sample distribution is skewed left and the median netbook laptop price is between $325 and $375.

Question 94

The pressure exerted by 1.00 mol of CO2 gas kept at 0°C in various containers is measured. In a 22.4 L container, the pressure is determined to be 0.995 atm. This value is essentially the same as pressure calculated for this gas by the ideal gas law.

What would be the difference between the real pressure of the gas and the pressure determined by the ideal gas law if the gas is compressed slightly to a volume of 0.400 L? What if the gas is compressed even more to a volume of 0.0200 L?

a. 0.400 L ideal pressure will be lower than real pressure; 0.0200 L ideal pressure will be much higher than real pressure.

b. 0.400 L ideal pressure will be lower than the real pressure; 0.0200 L ideal pressure will be even lower than real pressure.

c. 0.400 L ideal pressure will be higher than the real pressure; 0.0200 L ideal pressure will be even higher than real pressure.

d. 0.400 L ideal pressure will be higher than the real pressure; 0.0200 L ideal pressure will be much lower than real pressure.

Answer 94

a. 0.400 L ideal pressure will be lower than real pressure; 0.0200 L ideal pressure will be much higher than real pressure.

Question 95

Eukaryotic regulation checkpoints within a cell are verifying the quality and quantity of the cell’s DNA.

Which phase of the cell cycle most recently occurred?

a. Gap 0

b. Gap 1

c. Gap 2

d. Synthesis

Answer 95

c. Gap 2

Question 96

Eight bones form the cranial portion of the skull.

Which of them surrounds the external acoustic meatus?

a. Ethmoid

b. Occipital

c. Temporal

d. Sphenoid

Answer 96

c. Temporal