BIOL 240L Lab Exam Questions With Correct Answers

BIOL 240L Lab Exam Questions With
Correct Answers

Simple |Stain: |What |colour |are |unstained |bacterial |cells |under |a |microscope |- |CORRECT |
ANSWER✔✔-Transparent



Simple |Stain: |Why |is |it |called |a |simple |stain |(reference |colouring |of |the |cells) |- |CORRECT |
ANSWER✔✔-All |the |cells |get |stained |the |same |colour



Simple |Stain: |What |do |we |learn |about |the |cells? |- |CORRECT |ANSWER✔✔-Cell |morphology |
(size |and |shape)



Simple |Stain: |Give |some |examples |of |dyes |used |- |CORRECT |ANSWER✔✔-Methylene |blue, |
crystal |violet, |red |fuschin



Simple |Stain: |There |are |2 |main |types |of |simple |stains, |what |are |they? |- |CORRECT |
ANSWER✔✔-Positive |and |Negative



Simple |Stain: |In |a |positive |stain, |the |stain |is |__________ |- |CORRECT |ANSWER✔✔-alkaline |
(basic)



Simple |Stain: |What |gives |the |dye |colour? |- |CORRECT |ANSWER✔✔-The |chromophore



Simple |Stain: |the |chromophore |is |________ |- |CORRECT |ANSWER✔✔-cationic |(positively |
charged)

,Simple |Stain: |What |was |the |name |of |the |dye |we |used? |- |CORRECT |ANSWER✔✔-Methylene |
blue |(chloride)



Say |we |stained |Se, |Bs, |and |Ec |with |Methylene |blue

What |colour(s) |would |they |stain? |- |CORRECT |ANSWER✔✔-All |of |the |stains |would |be |coloured |
blue



What |is |the |purpose |of |flaming |the |mouth |of |the |test |tube? |- |CORRECT |ANSWER✔✔-Prevent |
cooler, |contaminated |air |from |getting |into |the |test |tube |and |to |sterilize |the |mouth |of |the |tube



How |does |heat |fixing |work? |- |CORRECT |ANSWER✔✔-Coagulates |the |bacterial |proteins |and |
adheres |them |to |the |surface |of |the |slide



What |would |happen |if |we |didn't |heat-fix? |- |CORRECT |ANSWER✔✔-Flooding |the |slide |with |dye
|and |washing |it |would |just |wash |away |the |smear




What |would |happen |in |we |heat |fixed |too |much? |- |CORRECT |ANSWER✔✔-The |proteins |would |
denature |and |the |bacterial |cells |would |be |deformed.



Microscope |Operation: |3 |main |parts |- |CORRECT |ANSWER✔✔-Lens |system, |Gears |for |
adjustment, |Light |source



Microscope |Operation: |What |magnifies |the |image? |(2 |parts) |- |CORRECT |ANSWER✔✔-The |
objective |lens |and |the |ocular |lens



Microscope |Operation: |What |parts |should |we |use |to |carry |a |microscope |- |CORRECT |
ANSWER✔✔-The |arm |and |the |base

, Microscope |Operation: |How |do |we |store |a |microscope |- |CORRECT |ANSWER✔✔-Stage |all |the |
way |up, |The |4X |objective |lens, |cord |wrapped



Microscope |Operation: |What |is |the |purpose |of |the |stage? |- |CORRECT |ANSWER✔✔-To |move |
the |slide |up, |down, |left, |right |to |observe |the |smear



Microscope |Operation: |what |is |the |nosepiece |- |CORRECT |ANSWER✔✔-The |part |of |the |
microscope |containing |the |objective |lenses



Microscope |Operation: |How |do |you |calculate |total |magnification? |- |CORRECT |ANSWER✔✔-
ocular |lens |x |objective |lens



Microscope |Operation: |What |is |the |relationship |between |the |iris |diaphragm |and |the |
condenser |- |CORRECT |ANSWER✔✔-The |iris |diaphragm |controls |the |amount |of |light |that |
passes |through |the |condenser



Microscope |Operation: |what |happens |when |too |much |light |is |passed |through |the |slide? |- |
CORRECT |ANSWER✔✔-Contrast |decreases



Microscope |Operation: |How |to |maximize |capture |of |your |image? |(lens |and |light |settings) |- |
CORRECT |ANSWER✔✔-match |lens |magnification |to |light |setting |like |100X |for |BOTH |(put |light |
all |the |way)



Microscope |Operation: |What |are |names |of |knobs |we |use |to |focus |the |image |on |the |slide? |- |
CORRECT |ANSWER✔✔-FINE |and |COARSE |adjustment |knobs



Microscope |Operation: |Instead |of |rotating |lenses |on |the |nosepiece |by |the |lens, |what |should |
we |use? |- |CORRECT |ANSWER✔✔-Rotate |by |knurled |ring