CSMLS Histology Fixation
Questions and answers 100%
verified.
The primary purpose of fixation is to:
a. stop enzymatic action
b. remove the water from the tissue
c. provide support for the tissue
d. autolyze the tissue CORRECT ANSWER.a. enzymes are proteins and
rendered inactive by fixation
Which of the following fixatives contains picric acid, formalin and acetic acid
a. Zenker
b. Helly
c. Bouin
d. Zamboni CORRECT ANSWER.c. Bouin
The ratio of fixative to tissue should be
a. 1:2
b. 5:1
0
c.15:2
0
d. 25:50 CORRECT ANSWER.c. 15 times to 20 times
Tissue must be washed in running water after fixation in:
a. Zenker solution
b. absolute alcohol
c. glyoxal
d. formalin CORRECT ANSWER.a. a pigment may be formed when tissue is
taken from a chromate-containing solution directly into alcoholic solution
, Which 2of 2the 2following 2fixatives 2contains 2formalin, 2potassium 2dichromate
2and 2mercuric 2chloride
a. Zenker
b. Helly
c. Carnoy
d. Orth 2CORRECT 2ANSWER.b. 2Helly
Precipitate 2left 2in 2tissues 2that 2have 2been 2fixed 2in 2solutions 2containing
2mercuric 2chloride 2may 2be
removed 2by 2immersion 2in:
a. running 2water
b. sodium 2thiosulfate
c. weak 2ammonia 2water
d. iodine 2CORRECT 2ANSWER.d. 2either 2Gram 2or 2Lugol 2iodine
Commercial 2stock 2formaldehyde 2solutions 2contain:
a. 4% 2formaldehyde
b. 10% 2formaldehyde
c. 37% 2to 240% 2formaldehyde
d. 98% 2to 2100% 2formaldehyde 2CORRECT 2ANSWER.c. 237% 2to 240 2%
2formaldehyde; 2diluted 21:10 2for 2use
Formalin 2pigment 2would 2most 2certainly 2be 2formed 2when 2the 2pH 2of 2the
2formalin 2is:
a. 5.0
b. 6.0
c. 7.0
d. 8.0 2CORRECT 2ANSWER.a. 25.0. 2While 2it 2is 2likely 2to 2happen 2with 2a 2pH 2of 26.0 2it
2would 2most 2certainly 2happen 2with 2pH 2of 25.0
Formalin 2pigment 2may 2be 2removed 2from 2tissue 2by
a. running 2water
b. alcoholic 2iodine
c. alcoholic 2picric 2acid
d. potassium 2permanganate 2CORRECT 2ANSWER.c. 2alcoholic 2picric 2acid
10% 2formalin 2is 2the 2same 2as:
a. 3 27% 2to 240% 2formaldehyde
b. 10% 2formaldehyde
c. 4% 2formaldehyde
d. 1% 2formaldehyde 2CORRECT 2ANSWER.c. 210% 2formalin 2is 2a 21:10 2dilution 2of
237% 2to 24% 2formaldehyde; 2therefore 2a 210% 2solution 2is 2the 2same 2as 23.7-4
2% 2formaldehyde
For 2best 2results 2when 2using 2formalin 2as 2a 2routine 2fixative, 2it 2must 2be 2made
a. acidic
b. basic
Questions and answers 100%
verified.
The primary purpose of fixation is to:
a. stop enzymatic action
b. remove the water from the tissue
c. provide support for the tissue
d. autolyze the tissue CORRECT ANSWER.a. enzymes are proteins and
rendered inactive by fixation
Which of the following fixatives contains picric acid, formalin and acetic acid
a. Zenker
b. Helly
c. Bouin
d. Zamboni CORRECT ANSWER.c. Bouin
The ratio of fixative to tissue should be
a. 1:2
b. 5:1
0
c.15:2
0
d. 25:50 CORRECT ANSWER.c. 15 times to 20 times
Tissue must be washed in running water after fixation in:
a. Zenker solution
b. absolute alcohol
c. glyoxal
d. formalin CORRECT ANSWER.a. a pigment may be formed when tissue is
taken from a chromate-containing solution directly into alcoholic solution
, Which 2of 2the 2following 2fixatives 2contains 2formalin, 2potassium 2dichromate
2and 2mercuric 2chloride
a. Zenker
b. Helly
c. Carnoy
d. Orth 2CORRECT 2ANSWER.b. 2Helly
Precipitate 2left 2in 2tissues 2that 2have 2been 2fixed 2in 2solutions 2containing
2mercuric 2chloride 2may 2be
removed 2by 2immersion 2in:
a. running 2water
b. sodium 2thiosulfate
c. weak 2ammonia 2water
d. iodine 2CORRECT 2ANSWER.d. 2either 2Gram 2or 2Lugol 2iodine
Commercial 2stock 2formaldehyde 2solutions 2contain:
a. 4% 2formaldehyde
b. 10% 2formaldehyde
c. 37% 2to 240% 2formaldehyde
d. 98% 2to 2100% 2formaldehyde 2CORRECT 2ANSWER.c. 237% 2to 240 2%
2formaldehyde; 2diluted 21:10 2for 2use
Formalin 2pigment 2would 2most 2certainly 2be 2formed 2when 2the 2pH 2of 2the
2formalin 2is:
a. 5.0
b. 6.0
c. 7.0
d. 8.0 2CORRECT 2ANSWER.a. 25.0. 2While 2it 2is 2likely 2to 2happen 2with 2a 2pH 2of 26.0 2it
2would 2most 2certainly 2happen 2with 2pH 2of 25.0
Formalin 2pigment 2may 2be 2removed 2from 2tissue 2by
a. running 2water
b. alcoholic 2iodine
c. alcoholic 2picric 2acid
d. potassium 2permanganate 2CORRECT 2ANSWER.c. 2alcoholic 2picric 2acid
10% 2formalin 2is 2the 2same 2as:
a. 3 27% 2to 240% 2formaldehyde
b. 10% 2formaldehyde
c. 4% 2formaldehyde
d. 1% 2formaldehyde 2CORRECT 2ANSWER.c. 210% 2formalin 2is 2a 21:10 2dilution 2of
237% 2to 24% 2formaldehyde; 2therefore 2a 210% 2solution 2is 2the 2same 2as 23.7-4
2% 2formaldehyde
For 2best 2results 2when 2using 2formalin 2as 2a 2routine 2fixative, 2it 2must 2be 2made
a. acidic
b. basic
