CLSC 410 - Exam 1 Questions and Answers Already Passed Latest Update 2025-2026
Module 1 - Answers
Accuracy - Answers how close the result is to the true value
Precision - Answers how close multiple results are to each other
In a clinical setting we strive for. . . - Answers - both accuracy and precision
- but this is a balancing act because one can never be both 100% accurate and precise
Analytical Sensitivity - Answers ability of method to detect the smallest amount of a substance
Analytical Specificity - Answers ability of method to detect only what you are assaying = minimal
interference!
What is a reference interval/What is it used for? - Answers - a range of values from a reference
population
- used for comparison of results
- not everyone is going to fall within this range; those that don't are indicated as being sick
- the range is specific to the method
The 5 Rules for Rounding - Answers 1. Express molecular weight in whole numbers
2. if the value <5, leave it
3. if the value >5, increase by one
4. if the value = 5: leave it if the proceeding number is even; increase by one if the proceeding
number is odd
5. ONLY ROUND AT FINAL STEP
Metric system units - Answers n = 10⁻⁹
µ = 10⁻⁶
m = 10⁻³
c = 10⁻²
d = 10⁻¹
k = 10³
, 1 dL = 100 mL
Celsius ---> Fahrenheit - Answers (C * 1.8) + 32 = F
Fahrenheit ---> Celsius - Answers (F − 32) * 0.556 = C
Fahrenheit ---> kelvin - Answers 1. convert from Fahrenheit to Celsius
2. Add 273
Module 2 - Answers
Simple dilutions = - Answers (sample volume) ÷ (sample volume + diluent volume)
Quantity sufficient (QS) rule - Answers - add sufficient amount of diluent to get the total volume
- always include when question asks HOW to do/make a sample
To find the new concentration from a diluted sample such as in serial dilution problems . . . -
Answers - dilution x concentration = new concentration
- always assume the calibrator (standard) isn't diluted, unless stated otherwise
Hydrates - Answers - often used to make up solutions
- occur when water molecule is attached to a salt
- so when dealing with them, you must account for the water molecule = set up a ratio to
convert from hydrates to anhydrous
Specific Gravity - Answers - the weight of a solid/liquid ÷ the weight of an equal volume of water
expressed as per mL
- 1 mL of water = mass of 1 g
- used in making solutions of concentrated chemicals; use along with the purity to determine the
amount of substance/volume.
Percentage Solutions - Answers 1. Weight/volume (w/v): used when solute is mixed with
solvent; ex: 15% NaCl = 15 g NaCl and qs to 100 mL with diluent
2. Volume/volume (v/v): liquid in a liquid solvent; ex: 10% ethanol = 10 mL of ethanol and qs to
100 mL with diluent
Ex simple dilution problem: A procedure calls for a 1/250 dilution of urine. Keeping the total
volume to 5 mL,
how would you dilute the specimen? - Answers 1. Set up a ratio: X/5 = 1/250;
Module 1 - Answers
Accuracy - Answers how close the result is to the true value
Precision - Answers how close multiple results are to each other
In a clinical setting we strive for. . . - Answers - both accuracy and precision
- but this is a balancing act because one can never be both 100% accurate and precise
Analytical Sensitivity - Answers ability of method to detect the smallest amount of a substance
Analytical Specificity - Answers ability of method to detect only what you are assaying = minimal
interference!
What is a reference interval/What is it used for? - Answers - a range of values from a reference
population
- used for comparison of results
- not everyone is going to fall within this range; those that don't are indicated as being sick
- the range is specific to the method
The 5 Rules for Rounding - Answers 1. Express molecular weight in whole numbers
2. if the value <5, leave it
3. if the value >5, increase by one
4. if the value = 5: leave it if the proceeding number is even; increase by one if the proceeding
number is odd
5. ONLY ROUND AT FINAL STEP
Metric system units - Answers n = 10⁻⁹
µ = 10⁻⁶
m = 10⁻³
c = 10⁻²
d = 10⁻¹
k = 10³
, 1 dL = 100 mL
Celsius ---> Fahrenheit - Answers (C * 1.8) + 32 = F
Fahrenheit ---> Celsius - Answers (F − 32) * 0.556 = C
Fahrenheit ---> kelvin - Answers 1. convert from Fahrenheit to Celsius
2. Add 273
Module 2 - Answers
Simple dilutions = - Answers (sample volume) ÷ (sample volume + diluent volume)
Quantity sufficient (QS) rule - Answers - add sufficient amount of diluent to get the total volume
- always include when question asks HOW to do/make a sample
To find the new concentration from a diluted sample such as in serial dilution problems . . . -
Answers - dilution x concentration = new concentration
- always assume the calibrator (standard) isn't diluted, unless stated otherwise
Hydrates - Answers - often used to make up solutions
- occur when water molecule is attached to a salt
- so when dealing with them, you must account for the water molecule = set up a ratio to
convert from hydrates to anhydrous
Specific Gravity - Answers - the weight of a solid/liquid ÷ the weight of an equal volume of water
expressed as per mL
- 1 mL of water = mass of 1 g
- used in making solutions of concentrated chemicals; use along with the purity to determine the
amount of substance/volume.
Percentage Solutions - Answers 1. Weight/volume (w/v): used when solute is mixed with
solvent; ex: 15% NaCl = 15 g NaCl and qs to 100 mL with diluent
2. Volume/volume (v/v): liquid in a liquid solvent; ex: 10% ethanol = 10 mL of ethanol and qs to
100 mL with diluent
Ex simple dilution problem: A procedure calls for a 1/250 dilution of urine. Keeping the total
volume to 5 mL,
how would you dilute the specimen? - Answers 1. Set up a ratio: X/5 = 1/250;
