ANSWER KEY
Total Questions: 91
Total Time: 2 hours 45 minutes (165 minutes)
SECTION 1: READING
Time: 45 minutes
Questions: 22
Read each passage carefully and answer the questions that follow.
Passage 1 (Questions 1–4)
The Blood-Brain Barrier
The brain is a privileged organ, protected not only by the skull but also by a highly selective
semipermeable border called the blood-brain barrier (BBB). This barrier is formed by endothelial cells
lining the brain's capillaries, which are tightly joined together by structures known as tight junctions.
Unlike capillaries elsewhere in the body, those in the brain prevent most molecules from passively
diffusing out of the bloodstream into the brain tissue. Only small, lipid-soluble molecules (such as
oxygen, carbon dioxide, and certain anesthetic agents) can cross easily. Glucose—the brain's primary
fuel—requires specific transport proteins to enter. The BBB serves a crucial protective function,
shielding the brain from toxins, pathogens, and fluctuations in blood composition. However, it also
presents a major challenge for treating brain disorders, as many life-saving drugs (including most
antibiotics and chemotherapeutic agents) cannot cross it. Researchers are actively developing methods
to temporarily open the BBB or attach drugs to molecules that can sneak across.
1. According to the passage, what is the primary function of the blood-brain barrier?
A) To supply glucose to the brain
B) To protect the brain from harmful substances
C) To regulate blood pressure in the brain
D) To produce cerebrospinal fluid
2. Which of the following molecules can cross the BBB most easily?
A) Glucose
,B) A large antibiotic
C) Oxygen
D) A water-soluble toxin
3. The word "privileged" as used in the first sentence most nearly means:
A) Wealthy
B) Exposed
C) Specially protected
D) Highly active
4. What challenge does the BBB present for medicine?
A) It allows too many drugs into the brain.
B) It prevents many drugs from reaching brain tissue.
C) It causes brain tumors to grow faster.
D) It makes glucose unavailable to neurons.
Passage 2 (Questions 5–8)
The Importance of Hand Hygiene
Hand hygiene is the single most effective measure for preventing healthcare-associated infections
(HAIs). Despite its simplicity, compliance among healthcare workers remains alarmingly low, often
below 50%. The Centers for Disease Control and Prevention (CDC) recommends using an alcohol-based
hand rub (ABHR) for routine decontamination, except when hands are visibly soiled, in which case soap
and water must be used. ABHRs are preferred because they act quickly, require less time, and are less
damaging to skin than repeated soap-and-water washing. However, ABHRs are ineffective against
certain pathogens, including Clostridioides difficile and norovirus. For these, vigorous handwashing with
soap and water is necessary. Studies show that multimodal interventions—including education,
reminders, easy access to hand sanitizers, and feedback on performance—can significantly improve
compliance. Nurses, who have the most frequent patient contact, play a key role in modeling proper
hand hygiene for both colleagues and patients.
5. According to the CDC, when should soap and water be used instead of alcohol-based hand rub?
A) For routine decontamination between patients
B) When hands are visibly dirty or soiled
C) After removing gloves
D) Before administering oral medications
6. Which pathogen is specifically mentioned as NOT killed by alcohol-based hand rubs?
A) Staphylococcus aureus
B) Influenza virus
C) Clostridioides difficile
D) Candida albicans
, 7. The author implies that hand hygiene compliance among healthcare workers is:
A) Excellent and above 90%
B) Improving rapidly with new technology
C) Lower than it should be
D) Unnecessary for nurses
8. What does "multimodal interventions" refer to in the passage?
A) Using only alcohol-based hand rubs
B) A combination of strategies to improve hand hygiene
C) Replacing soap with sanitizer in all situations
D) Punishing workers who forget to wash hands
Passage 3 (Questions 9–12)
Vital Signs: Temperature
Body temperature is a vital sign that reflects the balance between heat production and heat loss.
Normal core temperature ranges from 36.5°C to 37.5°C (97.7°F to 99.5°F), though it varies by time of
day (lowest in early morning, highest in late afternoon), age (older adults tend to be cooler), and
menstrual cycle. Fever (pyrexia) is defined as a temperature above 38.0°C (100.4°F) and is a
physiological response to infection or inflammation, triggered by pyrogens (substances that reset the
hypothalamic set point). Hyperthermia, in contrast, occurs when the body's heat-regulating mechanisms
fail, often due to environmental heat exposure, and the set point remains normal while body
temperature rises uncontrollably. Hypothermia, a core temperature below 35.0°C (95.0°F), can result
from prolonged cold exposure, shock, or certain metabolic disorders. Accurate measurement requires
selecting the appropriate method (oral, rectal, axillary, tympanic, or temporal) based on patient
condition. Rectal temperatures are considered the gold standard for core temperature but are invasive;
axillary readings are safest but least accurate, typically reading 0.5°C lower than oral.
9. What is the normal core temperature range according to the passage?
A) 35.0°C – 36.0°C
B) 36.5°C – 37.5°C
C) 37.5°C – 38.5°C
D) 38.0°C – 39.0°C
10. How does hyperthermia differ from fever?
A) Hyperthermia is caused by pyrogens; fever is not.
B) In hyperthermia, the hypothalamic set point is normal; in fever, it is raised.
C) Hyperthermia is always lower than fever.
D) Fever only occurs in children; hyperthermia occurs in adults.
11. Which temperature measurement method is described as the "gold standard"?
A) Oral
B) Axillary