100+ Free MLS Practice Questions
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On a Gram stain, decolorization with acetone-alcohol removes which dye complex from gram-negative bacteria?
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Key Facts: MLS Exam
210
Total Items
AMT MLS
3.5 hrs
Exam Time
AMT
$245
Exam Fee
AMT
2023
MT → MLS rebrand
AMT aligned with ASCP MLS
AMT MLS is the bachelor's-level generalist clinical lab credential (formerly AMT MT, rebranded 2023, aligned with ASCP MLS branding). 210 items, 3.5 hours, $245. Master Westgard QC rules, ABO/Rh and antibody screen workflow, acute hemolytic transfusion reaction protocol, Strep/Staph identification, Friedewald LDL formula, and HER2 IHC/FISH cascade.
Sample MLS Practice Questions
Try these sample questions to test your MLS exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.
1A Levey-Jennings chart shows a single control value falling more than 3 standard deviations from the mean. Which Westgard rule is violated?
2Which Westgard rule indicates systematic shift when 10 consecutive control values fall on one side of the mean?
3A waived complexity test under CLIA requires which of the following?
4A reference range for hemoglobin in an adult male is best represented by:
5A patient has MCV of 70 fL with low ferritin and elevated TIBC. The most likely diagnosis is:
6A bone marrow shows >20% promyelocytes with Auer rods and faggot cells. The patient develops DIC. The most likely diagnosis is:
7The Philadelphia chromosome t(9;22) producing the BCR-ABL fusion is most associated with:
8Which of the following extends the prothrombin time (PT) but not the partial thromboplastin time (PTT)?
9A mixing study shows correction of prolonged PTT after 1:1 mixing with normal plasma. This indicates:
10Anti-A and anti-B antibodies in human serum are typically of which immunoglobulin class?
About the MLS Exam
AMT bachelor's-level generalist clinical laboratory credential. AMT retired the legacy "MT" (Medical Technologist) designation in 2023 and now uses MLS branding aligned with ASCP. Covers chemistry, hematology, coagulation/hemostasis, urinalysis/body fluids, immunology/serology, immunohematology/blood bank, microbiology, and general lab practice (QC, CLIA, safety, LIS).
Questions
210 scored questions
Time Limit
3.5 hours
Passing Score
Scaled (AMT-set)
Exam Fee
$245 (AMT)
MLS Exam Content Outline
Chemistry
Glucose, electrolytes, BUN/Cr, lipids (Friedewald), enzymes (AST/ALT, alk phos), troponin, BNP
Hematology
CBC, smear, anemia classification (MCV-based), leukemias (APL t(15;17), CML t(9;22))
Blood Bank / Immunohematology
ABO/Rh, antibody screen IAT, crossmatch, transfusion reactions, components, RhoGAM
Microbiology
Gram stain, culture media, Strep/Staph/E. coli/Pseudomonas ID, susceptibility, parasites
Coagulation
PT/PTT/INR, mixing study, factor deficiencies, DIC, vWD, heparin/DOAC monitoring
Immunology / Serology
Antibody testing, ANA, hepatitis serology, HIV 4th gen, syphilis (RPR/FTA), complement
Urinalysis / Body Fluids
Urine sediment, casts (RBC GN, WBC pyelo, waxy CKD), CSF/synovial/pleural analysis
General Lab Management
Westgard QC, CLIA complexity, safety (BBP, NFPA, chem hygiene), LIS, delta checks
How to Pass the MLS Exam
What You Need to Know
- Passing score: Scaled (AMT-set)
- Exam length: 210 questions
- Time limit: 3.5 hours
- Exam fee: $245
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
MLS Study Tips from Top Performers
Frequently Asked Questions
What are the Westgard QC rules?
Westgard multi-rule QC: 1-3s (1 control >3SD = REJECT); 1-2s (warning, trigger further evaluation); 2-2s (2 consecutive same side >2SD = reject, systematic error); R-4s (range >4SD between controls = random error); 4-1s (4 consecutive >1SD same side = bias); 10-x (10 consecutive same side of mean = shift). Distinguish random vs systematic error to guide troubleshooting.
How is acute hemolytic transfusion reaction managed?
Most often ABO incompatibility from clerical error. Symptoms: fever, chills, back/flank pain, hemoglobinuria, hypotension, DIC. STOP transfusion immediately, maintain IV access with NS, send remaining unit + post-transfusion blood/urine to blood bank, monitor renal function, supportive care. Investigate cause (recheck sample identity, repeat ABO/Rh on pre/post samples, DAT). Document and report per facility policy.
What is the Friedewald formula?
LDL-C = Total Cholesterol − HDL-C − (Triglycerides / 5), valid only when triglycerides <400 mg/dL. Above 400, Friedewald becomes unreliable and direct LDL measurement is required. Newer Martin-Hopkins formula uses adjustable factor for TG range. Always calculate after 9-12 hour fast (TG most affected by recent meal).
How should I study for AMT MLS?
Plan 120-200 hours over 16-20 weeks. AMT MLS covers 8 generalist domains — focus weighted study on Chemistry, Hematology, Blood Bank, and Microbiology (each ~15%). Drill Westgard QC rules, ABO/Rh discrepancies, Strep/Staph identification, hepatitis serology patterns, and CSF interpretation. AMT MLS overlaps heavily with ASCP MLS — most prep materials work for both.