Lab Exam Last-Minute Studying Flashcards
What is the definition of a negative scale, and a log scale?
Negative = as pH goes down, H+ concentration goes up
Log scale = Difference between pH of 5 and 4 is x10 the number of H+ ions
What do buffers do? Name the main 3.
Prevent drastic changes in pH but do NOT eliminate H+ ions.
Protein, phosphate, buffer.
How does the protein buffer system prevent drastic changes in pH?
Carboxyl chain acts as weak acid, amino acts as weak base, so it can help in a variety of ways.
Write out the equation of a bicarbonate acid buffer. What acts as a weak base? What acts as a weak acid?
H2CO3 <–> H+ and HCO3.
H2CO3 will act as a weak acid, HCO3 will act as a weak base.
Which molecule in phosphate buffers acts as a weak base? Weak acid?
Base: HPO4
Acid: H2PO4
What is the purpose of an iris diaphragm, stage condenser?
Iris diaphragm controls the amount of light moving through specimen.
Stage condenser focuses light.
What does methylene blue stain?
All acidic components of cell. It will stain plasma membrane, nucleic membrane, and nucleic acids that may be free-floating.
What are the 4 steps of staining blood?
- HEMA 3 fixative
- solution I red
- solution II blue
- rinse with water
Which leukocyte has…
1. multi-lobed nucleus
2. U-shaped nucleus
3. orange color
4. blue cytoplasm
- neutrophils
- monocytes
- eosinophils
- basophils
Differentiate between hypotonic, isotonic, hypertonic solutions. Which solution of NaCl is isotonic to erythrocytes.
- hypotonic = lots of water
- isotonic = same []
- hypertonic = low water
0.9% solution of NaCl is isotonic to erythrocytes.
Compare female, male, and infant hematocrit.
Female = 36-46%
Male = 42-52%
Infant = 42-65%
What do high and low hematocrit values indicate?
High = dehydration, altitude, smoking
Low = vitamin deficiency, anemia
What are the 4 types of physical examination of urine?
quantity, color, transparency, specific gravity
What does high and low urine production indicate?
High = overhydration, diabetes, chronic infections
Low = acute infections, dehydration, shock
What are the parts of a chemical examination of a urine test?
blood
pH
nitrite
glucose
protein
urobilinogen
ketones
WBCs
Where does bilirubin come from? How does it become urobilin?
Comes from hemoglobin breakdown (heme). Transported to liver, conjugated with glucuronic acid to become bilirubin diglucuronide. Goes to intestines to become urobilin and stercobilin.
What are risk factors for GBS in newborns?
- premature birth
- prolonged rupture of membranes
- mother colonized by GBS
What are the three types of hemolysis? What strep groups do they have?
alpha-hemolytic: green, partial
beta-hemolytic: clear, complete
gamma-hemolytic, red, none
Group A/B have beta-hemolytic, group D has alpha and gamma-hemolytic.
What is the physical difference between gram negative and gram positive (testing)?
Negative = stains purple with crystal violet, red with sanfranin
Positive = colourless
Differentiate between diplo, staphylo, streptococci.
Diplo = two
Staphylo = clumps
Strepto = chains
