introduction

Question 1

define histology in short

Answer 1

histo - tissue
logos - study

Question 2

what is histology?

Answer 2

study of the microscopic structure of the normal human body in relation to its function using light and electron microscope

Question 3

what are the steps in preparation of histologic sections for light microscopy?

Answer 3

1. collection
2. fixation
3. dehydration
4. clearing
   5.embedding
5. sections
6. staining

Question 4

Fixation
1. aim
2. fixative
3. methods

Answer 4

1. to avoid tissue autolysis/damage by bacteria so as to preserve the structure and molecular function
2. Formalin (buffered isotonic solution of 4 percent formaldehyde)
3. tissue is immersed in fixative, intravascular perfusion

Question 5

dehydration
1. aim
2.method

Answer 5

1. remove water from the tissue
2. start with 70% alcohol conc. to 100%.
   water is completely removed from tissue & replaced with alcohol

Question 6

clearing

Answer 6

alcohol is removed in toluene , xylene, and chloroform

Question 7

embedding
1.aim

Answer 7

to obtain with micro tome, tissue must be infiltrated.
wax is most common.

Question 8

sectioning and embedding
1.aim
2. instrument
3. thickness
4. methods

Answer 8

1. to get thin sections so the light can pass through the tissue.
   2.microtome
2. 1um ~ 10um
3. harden tissue sliced into sections

Question 9

staining
1. aim
2. dyes

Answer 9

1. to make various tissue components conspicuous.
   to distinguish the different cells and tissues
2. hematoxylin , eosin ( H & E staining ）

Question 10

describe hematoxylin

Answer 10

basic dye
blue
acidic structure

Question 11

what is basophilia
give example

Answer 11

tissue component that stain readily with basic dyes
nucleus,rER, ribosome

Question 12

describe eosin

Answer 12

acidic dye
pink

Question 13

what is acidophilia
example

Answer 13

tissues components that stain readily with acidic dyes
cytoplasm

Question 14

neutrophilic definition and example

Answer 14

not stained by HE
GOLGI

Question 15

impregnation technique

Answer 15

a simple histological procedure that reveals complete three-dimensional neuron morphology

Question 16

light microscope

Answer 16

conventional
phase contrast
differential interference
polarizing
con-focal
fluorescence microscope

Question 17

resolution power of light microscope

Answer 17

the smallest distance between 2 particles at which they can be seen as separate objects
light microscope 0.1um
1mm = 1000um

Question 18

electron microscopy

Answer 18

transmission electron microscope
scanning electron microscope
0.1 nm 1um = 1000nm
magnification = 100000 times

Question 19

difference between LM & TM

Answer 19

EM
black & white LM : 3d and everything else vice versa
high resolution
electron dense
electron lucent

Question 20

Histochemistry & cytochemistry use

Answer 20

reveals chemical composition in situ based on specific chemical reaction
in high-affinity interaction between macro-molecules

Question 21

cell components and tests

Answer 21

1. sugar - PAS
2. lipid - sudan iii or sudan black reaction
3. nucleic acid - feulgen reaction
   enzyme -enzyme — chemical staining

Question 22

PAS reaction name

Answer 22

periodic acid schiff reactiom

Question 23

PAS reaction

Answer 23

sugar (glycol groups) + periodic acid = aldehyde residues + schiff reagent (insoluable colored/ electron dense compound seen in LM/EM)= purple residues

Question 24

immunochemistry

Answer 24

reveals specific protiens in situ
based on antigen-antibody reaction

Question 25

immunochemistry process

Answer 25

antigen retrieval (AR), addition of primary antibody, application of a secondary antibody that binds the primary antibody, and addition of a detection reagent to localize the primary antibody