Question 1

Upon receiving a serum sample for protein electrophoresis, which you perform using agarose gel, you note that the specimen is hemolyzed. How would hemolysis affect the banding pattern of this type of electrophoresis?

Accepted Answer

Answer reason: Hemolysis releases free hemoglobin, which migrates in the β region on serum protein electrophoresis, producing an increased β-globulin band.

Question 2

Which cerebrospinal fluid (CSF) value is negative if the CSF is normal after a lumbar puncture?

Accepted Answer

Answer reason: Normal CSF contains no red blood cells; their presence indicates hemorrhage or traumatic tap. Small WBCs may be present, and protein is normally present.

Question 3

What is the confirmatory test for AIDS?

Accepted Answer

Answer reason: Western blot is the traditional confirmatory test for HIV after a positive ELISA. CD4 counts monitor disease status, and VDRL is for syphilis.

Question 4

What bilirubin level indicates pathological jaundice?

Accepted Answer

Answer reason: In neonates, a total serum bilirubin above about 15 mg/dL is used as a threshold suggesting pathologic jaundice; lower values are more consistent with physiologic jaundice or normal.

Question 5

Which type of urinary crystal appears as brownish, thorn-apple–shaped structures under microscopy?

Accepted Answer

Answer reason: Ammonium biurate crystals have a characteristic brownish “thorn-apple” spiky appearance, easily distinguishable from other crystal types.

Question 6

Which laboratory test is used to monitor long-term glucose control in diabetic patients?

Accepted Answer

Answer reason: HbA1c reflects the average blood glucose level over the preceding 2–3 months and is used to evaluate chronic glycemic control.

Question 7

ASO Test is related to......?

Accepted Answer

Answer reason: ASO (anti-streptolysin O) titer detects antibodies against streptolysin O produced by Group A Streptococcus. Elevated ASO levels indicate a recent streptococcal infection and support the diagnosis of post-streptococcal diseases such as rheumatic fever. It is not used for typhoid, viral, or cholera fevers. Therefore, rheumatic fever is the correct association.

Question 8

Blood Sugar Fasting Normal Range?

Accepted Answer

Answer reason: Normal fasting plasma glucose for adults is approximately 70–99 mg/dL per ADA guidelines. A range of 70–90 mg/dL falls within normal limits. A value of 100–125 mg/dL suggests impaired fasting glucose (prediabetes), and 150–200 mg/dL is hyperglycemic. The 50–120 range includes hypoglycemia and is not an accepted normal range.

Question 9

False positive VDRL test may be present in all except?

Accepted Answer

Answer reason: VDRL is a non-treponemal test detecting antiphospholipid antibodies, which can appear in many conditions causing biologic false positives, including viral hepatitis, infectious mononucleosis, and lepromatous leprosy. These conditions can generate anticardiolipin antibodies independent of syphilis. Condylomata acuminata (HPV-related genital warts) does not typically produce such antibodies and is not a recognized cause of biologic false-positive VDRL. Therefore, it is the exception.

Question 10

'Mantoux test' is for?

Accepted Answer

Answer reason: The Mantoux test is the tuberculin skin test that screens for infection with Mycobacterium tuberculosis. It involves intradermal injection of purified protein derivative (PPD) and measuring induration at 48–72 hours to detect a delayed-type hypersensitivity response. A positive result suggests TB infection (latent or active), while BCG vaccination and non-tuberculous mycobacteria can cause false positives; immunosuppression can yield false negatives.

Question 11

The Test That Is Most Specific For Myocardial Damage Is?

Accepted Answer

Answer reason: Cardiac troponin I is highly specific to myocardial tissue and is the preferred biomarker for diagnosing myocardial injury. It rises within 3–4 hours after infarction, peaks around 12–24 hours, and remains elevated for up to 7–10 days, improving diagnostic sensitivity and specificity. CK-MB is less specific because it can increase with skeletal muscle injury, and total CK and myoglobin are even less specific. Therefore, troponin I is the most specific test for myocardial damage.

Question 12

Normal oxygen saturation is above?

Accepted Answer

Answer reason: In healthy adults, normal peripheral oxygen saturation (SpO2) on room air is typically 95–100%. Values below 90% indicate hypoxemia and correlate with a PaO2 around 60 mmHg on the oxyhemoglobin dissociation curve. Therefore, the threshold indicating normal is above 95%.

Question 13

Normal pH of urine is?

Accepted Answer

Answer reason: Normal urine is slightly acidic with an average pH around 6 (typical range 4.5–8). The kidneys excrete acid to maintain systemic acid–base balance, producing this mildly acidic urine. A pH of 7 is neutral and 8 is alkaline, which may occur with certain diets or UTIs; 5 is more acidic than the usual average.

Question 14

Visualization of the stomach is known as -------?

Accepted Answer

Answer reason: Gastroscopy (upper GI endoscopy) uses a flexible endoscope inserted via the mouth to directly visualize the gastric mucosa and lumen. Laparotomy is an open surgical incision into the abdomen, not specifically for visualizing the stomach lining. Gastrectomy refers to surgical removal of part or all of the stomach. The term “Antroscopoy” is not standard; the appropriate diagnostic visualization is gastroscopy.

Question 15

Which test uses sound waves to check the heart?

Accepted Answer

Answer reason: An echocardiogram uses ultrasound (high-frequency sound waves) to create real-time images of cardiac structures and assess function and blood flow. ECG records electrical activity, X-ray uses ionizing radiation, and MRI uses magnetic fields—not sound waves. Therefore, the test based on sound waves is an echocardiogram (Echo).

Question 16

The common urine test for UTI is _____?

Accepted Answer

Answer reason: Urine culture is the standard diagnostic test to confirm a urinary tract infection by identifying the causative organism and providing antibiotic susceptibility. It is performed on a urine specimen and directly addresses UTI. ECG, MRI, and X-ray do not assess urine or diagnose UTIs and are unrelated to routine UTI evaluation.

Question 17

Pancreatitis patient, investigation should be done to diagnose?

Accepted Answer

Answer reason: Serum amylase rises rapidly in acute pancreatitis and levels three times the upper limit of normal strongly support the diagnosis. Although serum lipase is more specific, it is not listed among the options. ALT reflects hepatocellular injury, while ALP and GGT are cholestatic liver enzymes, not primary markers for pancreatic inflammation.

Question 18

Normal WBC count is .......... cells/mm3 of blood?

Accepted Answer

Answer reason: The normal total leukocyte (WBC) count in adults is approximately 4,000–11,000 cells per mm3 (or per microliter) of blood. Option a refers to the typical red blood cell count (about 4.5–6 million/mm3). Option c reflects platelet counts using the Indian numbering system (150,000–450,000 ≈ 1.5–4.5 lakhs). Option d is far below the normal total WBC range and may reflect a subset count, not the total leukocyte count.

Question 19

A creatinine test is conducted to assess?

Accepted Answer

Answer reason: Serum creatinine is a waste product of muscle metabolism that is filtered by the renal glomeruli. When glomerular filtration rate declines, creatinine accumulates, making it a key indicator of renal function. It is not a primary test of hepatic or cardiac function.

Question 20

HbA1c level used for diagnosis of diabetes?

Accepted Answer

Answer reason: According to ADA diagnostic criteria, diabetes can be diagnosed by an HbA1c ≥ 6.5% using a standardized assay, typically confirmed on a repeat sample. An HbA1c of 5.7–6.4% indicates prediabetes, not diabetes. A value of 7% is commonly used as a treatment target rather than a diagnostic threshold.

Question 21

The ideal Total Dissolved Solids (TDS) for lab-grade distilled water?

Accepted Answer

Answer reason: Lab-grade distilled water should have virtually no dissolved ions to prevent interference with assays and equipment. TDS near zero (typically

Question 22

HbA1c diagnostic level for Diabetes is?

Accepted Answer

Answer reason: Per ADA diagnostic criteria, diabetes mellitus can be diagnosed with an HbA1c ≥ 6.5% using a standardized, NGSP-certified assay. Levels 5.7–6.4% indicate prediabetes, while 5.5% is within normal/near-normal range. Thresholds like ≥ 7.5% or ≥ 8.0% are sometimes used as treatment targets or for risk stratification, not for initial diagnosis.

Question 23

The normal human blood PH is?

Accepted Answer

Answer reason: Normal arterial blood pH is tightly regulated between 7.35 and 7.45 by the bicarbonate–carbonic acid buffer system with respiratory and renal compensation. Values below 7.35 indicate acidemia, and values above 7.45 indicate alkalemia. The other ranges listed are incompatible with physiologic function and survival, making 7.35–7.45 the only correct range.

Question 24

Which compound is used for diagnosis of brain tumor?

Accepted Answer

Answer reason: Iodine-131, often as radioiodinated serum albumin, has been used to image brain tumors because areas with a disrupted blood–brain barrier concentrate the tracer, allowing gamma-camera detection. I-129 is stable and not suitable for imaging. I-130 and I-132 have limited clinical use and are not standard for brain tumor diagnosis. I-131 emits gamma radiation adequate for diagnostic scanning while also being widely available.

Question 25

Liver function tests detect?

Accepted Answer

Answer reason: Liver function tests (e.g., ALT, AST, ALP, bilirubin) assess hepatocellular injury and cholestasis. Elevations indicate liver damage or impaired hepatic processing rather than renal, cardiac, or pulmonary dysfunction. These labs help diagnose and monitor hepatitis, cirrhosis, biliary obstruction, and drug-induced liver injury.

Question 26

Normal urine pH is?

Accepted Answer

Answer reason: Normal urine is slightly acidic, with a typical range of about 4.5 to 8 and an average near pH 6. A pH of 2–3 would be extremely acidic and not physiologic. Values of 8–10 are markedly alkaline and suggest factors such as urea-splitting bacteria, diet, or specimen issues. Therefore, the best answer is 4.5–8.

Question 27

Hemoglobin is checked by...?

Accepted Answer

Answer reason: Hemoglobin concentration is measured from a blood specimen, typically as part of a complete blood count (CBC) using automated analyzers. Imaging modalities such as X-ray, CT scan, or ultrasound cannot quantify hemoglobin. Therefore, the appropriate method to check hemoglobin is a laboratory blood test.

Question 28

Kidney stones are detected by?

Accepted Answer

Answer reason: Renal ultrasonography is a common diagnostic imaging test used to detect kidney stones, especially when avoiding radiation (e.g., pregnancy) and to assess for hydronephrosis/obstruction. EEG evaluates brain electrical activity, ECG evaluates cardiac electrical activity, and CBC is a blood test that does not localize or image stones. Therefore, ultrasound is the best answer among the options provided.

Question 29

What is the normal range of serum potassium?

Accepted Answer

Answer reason: The normal serum potassium reference range in adults is approximately 3.5–5.0 mEq/L. Values below this suggest hypokalemia, which increases risk for muscle weakness and dysrhythmias. Values above this suggest hyperkalemia, which can cause dangerous cardiac conduction abnormalities (e.g., peaked T waves, widened QRS). Therefore, 3.5–5.0 is the correct normal range among the options.

Question 30

Which test detects protein in urine?

Accepted Answer

Answer reason: The heat and acetic acid test is a classic qualitative test for protein (especially albumin) in urine, producing turbidity/coagulation on heating that persists after adding acetic acid. Benedict’s test detects reducing sugars (e.g., glucose) rather than protein. Rothera’s test is used to detect ketone bodies in urine. Litmus test assesses acidity/alkalinity (pH), not urinary protein.

Question 31

What is the fixative used for pap smear?

Accepted Answer

Answer reason: Conventional Pap smears require immediate wet fixation to prevent air-drying artifact that distorts nuclear and cytoplasmic detail needed for cytologic interpretation. The standard fixative is 95% ethyl alcohol (or an alcohol-based spray fixative), which rapidly preserves cellular morphology. Air drying is contraindicated for Pap staining, while formalin is used for tissue histopathology rather than exfoliative cytology slides. Therefore, 95% ethyl alcohol is the best answer.

Question 32

Normal total WBC count in adults is?

Accepted Answer

Answer reason: The typical normal adult total leukocyte (WBC) count is about 4,000–11,000 per cubic millimeter (µL). Values below this range suggest leukopenia and can be seen with bone marrow suppression or some viral illnesses, while values above suggest leukocytosis often due to infection, inflammation, stress, or hematologic malignancy. The other ranges listed are either abnormally low or represent leukocytosis.

Question 33

The test commonly used for diagnosis of malaria is?

Accepted Answer

Answer reason: The most common and standard diagnostic test for malaria is microscopic examination of peripheral blood smears (thick and thin films) to directly detect Plasmodium parasites and estimate parasitemia. Widal test is used for typhoid fever, and Mantoux test is for tuberculosis screening. ELISA may be used in some settings for serology, but it is not the routine first-line test for acute malaria diagnosis because it does not reliably indicate current parasitemia.

Question 34

What is the normal serum ferritin level in females?

Accepted Answer

Answer reason: Serum ferritin reflects total body iron stores, and typical reference ranges are sex-specific. In adult females, a commonly accepted normal range is approximately 12–150 ng/mL, making this option the best match. The 0.15–0.25 ng/mL option is far below physiologic values and resembles a unit/decimal error. The other ranges are too narrow and do not represent standard laboratory reference intervals for women.

Question 35

Which diagnostic test is most definitive for confirming lung cancer?

Accepted Answer

Answer reason: The definitive confirmation of lung cancer requires histologic diagnosis, which is obtained by tissue biopsy. Bronchoscopy with biopsy allows direct visualization of airways and sampling of suspicious lesions for pathology, establishing malignancy type. Chest X-ray and CT scan can detect masses and guide staging but cannot confirm cancer without tissue. Sputum cytology may detect malignant cells but has lower sensitivity and is not considered the most definitive test.

Question 36

EDTA Used For___?

Accepted Answer

Answer reason: EDTA (commonly in lavender-top tubes) is an anticoagulant that chelates calcium, preventing clotting and preserving cellular morphology. This makes it the standard specimen tube for hematology tests like the complete blood count (CBC), including hemoglobin/hematocrit, RBC indices, WBC count, and platelets. Blood sugar testing is typically done in gray-top tubes (fluoride/oxalate), while electrolytes and lipid profiles are commonly measured from serum (red/gold) or heparinized plasma (green).

Question 37

Oxygen saturation is measured by?

Accepted Answer

Answer reason: Oxygen saturation (SpO2) is noninvasively measured using a pulse oximeter, which estimates arterial hemoglobin oxygen saturation via light absorption at two wavelengths. A manometer measures pressure (e.g., blood pressure), a pulse transducer detects pulse/pressure waveforms, and a thermometer measures temperature. Therefore, the correct device for oxygen saturation is the pulse oximeter.

Question 38

Normal serum sodium level is?

Accepted Answer

Answer reason: The normal reference range for serum sodium (Na+) in adults is approximately 135–145 mEq/L. Values below this indicate hyponatremia and values above this indicate hypernatremia, both of which can significantly affect neurologic function due to osmotic fluid shifts. The other choices reflect ranges for other labs (e.g., 3.5–5.5 mEq/L is consistent with potassium), or are outside accepted sodium norms.

Question 39

Elisa test is used for detecting?

Accepted Answer

Answer reason: ELISA (enzyme-linked immunosorbent assay) is commonly used as a screening test to detect antibodies (and in some formats antigens) related to HIV infection. It is sensitive and designed to identify exposure/infection, with reactive results typically confirmed by a more specific test (e.g., immunoassay differentiation test or nucleic acid testing). Anemia and diabetes are not diagnosed by ELISA, and tuberculosis testing is more commonly done with AFB smear/culture, NAAT, or IGRA rather than standard ELISA screening.

Question 40

Which lab value is indicative of myocardial infarction?

Accepted Answer

Answer reason: Cardiac troponins (I and T) are highly sensitive and specific markers of myocardial injury and rise after myocardial infarction. Creatine kinase (especially CK-MB) typically increases rather than decreases in MI. D-dimer reflects fibrin degradation and is used for suspected thromboembolism (e.g., PE/DVT), not as a primary MI marker. Lactate is more related to tissue hypoperfusion and would not be expected to decrease in MI.

Question 41

Best diagnostic test for peptic ulcer?

Accepted Answer

Answer reason: Upper GI endoscopy is the best diagnostic test for peptic ulcer disease because it directly visualizes the gastric/duodenal mucosa and can confirm an ulcer’s presence, size, and stigmata of bleeding. It also allows biopsy to exclude malignancy (especially for gastric ulcers) and to evaluate for H. pylori when indicated. Ultrasound does not evaluate mucosal ulcers well, plain X-ray is not diagnostic (barium studies are less sensitive/specific than endoscopy), and blood pressure check is not a diagnostic test for ulcers.

Question 42

The test used to confirm malaria is?

Accepted Answer

Answer reason: Malaria is confirmed by detecting Plasmodium parasites or their antigens in blood. Rapid diagnostic tests (RDTs) detect malaria antigens (e.g., HRP2 or pLDH) and are widely used for confirmation, especially when microscopy is not immediately available. Widal test is for typhoid, LFT evaluates liver function, and ELISA is not the standard point-of-care confirmatory test for acute malaria in routine practice.

Question 43

Normal level of cholesterol is?

Accepted Answer

Answer reason: For adults, desirable (normal) total serum cholesterol is less than 200 mg/dL; values 200–239 mg/dL are borderline high and ≥240 mg/dL are high. Therefore, the best answer among the choices is

Question 44

What is the Glucose level of Normal CSF?

Accepted Answer

Answer reason: Normal CSF glucose is typically about two-thirds of the serum glucose concentration, commonly cited around 45–80 mg/dL. Values significantly below this range suggest impaired glucose transport or increased consumption in the CSF, as seen with bacterial meningitis or malignancy. The other options reflect typical ranges for serum glucose extremes or serum sodium and are not appropriate for CSF glucose.

Question 45

Dextrose normal saline used for infusion contains which one of the following?

Accepted Answer

Answer reason: Dextrose normal saline (D5NS) is 0.9% sodium chloride with 5% dextrose. Normal saline contains approximately 154 mEq/L of sodium and 154 mEq/L of chloride. A 5% dextrose solution corresponds to 5 g per 100 mL, whereas 50 g/100 mL would be 50% dextrose and is not used as standard maintenance IV fluid.

Question 46

The normal serum sodium level is?

Accepted Answer

Answer reason: Normal serum sodium is approximately 135–145 mmol/L (mEq/L) in most reference ranges. Among the choices, 132–142 mmol/L is the only range that substantially overlaps the accepted normal range and is closest overall. The other options describe severe hyponatremia (110–115, 90–105) or an abnormally high range that would include hypernatremia (140–160). Therefore, option C is the best answer.

Question 47

Which of the following acronyms is not a certification agency for phlebotomists?

Accepted Answer

Answer reason: NAACLS (National Accrediting Agency for Clinical Laboratory Sciences) accredits educational programs, including phlebotomy training programs, rather than certifying individual phlebotomists. In contrast, organizations like AMT provide individual professional certification credentials. Therefore, NAACLS is not a certification agency for phlebotomists.

Question 48

Increased level of potassium is called –?

Accepted Answer

Answer reason: An increased serum potassium level is termed hyperkalemia ("hyper" = high, "kal" = potassium, "emia" = in the blood). Hypokalemia refers to low potassium. The other options refer to different analytes: hypercalcemia is high calcium and hyperglycaemia is high blood glucose.

Question 49

A patient with severe vomiting has a serum potassium of 2.8 mEq/L. Which ECG change should the nurse expect?

Accepted Answer

Answer reason: Severe vomiting commonly causes hypokalemia, and a potassium of 2.8 mEq/L is consistent with clinically significant hypokalemia. Hypokalemia delays myocardial repolarization and slows conduction, classically producing ECG changes such as flattened/inverted T waves, ST depression, prominent U waves, and may prolong the PR interval. Peaked T waves are typical of hyperkalemia, not hypokalemia. The other listed options are not characteristic hallmark findings for hypokalemia compared with PR prolongation among the provided choices.

Question 50

Which electrolyte imbalance causes cardiac arrhythmias?

Accepted Answer

Answer reason: Hypokalemia increases myocardial excitability and delays ventricular repolarization, which predisposes the patient to dysrhythmias. Low potassium is classically associated with ECG changes such as ST depression, flattened T waves, and prominent U waves, and it can precipitate dangerous ventricular arrhythmias, especially in patients on digoxin or with underlying heart disease. While other electrolyte disturbances can affect rhythm, hypokalemia is a well-established common cause of clinically significant arrhythmias.

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