Introduction

Question 1

What are the 6 different levels of study?

Answer 1

Chemical
Cellular 
Tissues 
Organs
Organ systems
Human

Question 2

What is cytology?

Answer 2

The study of cells

Question 3

What is the functional unit of life?

Answer 3

Cells

Question 4

What is histology?

Answer 4

The study of tissues

Question 5

What are the four types of tissue?

Answer 5

Epithelium- protection
Muscular- movement
Nervous- control
Connective- support and transport

Question 6

In tissue preparation what are the 9 steps?

Answer 6

Fixation
Dehydration
Clearing
Infiltration
Embedding
Sectioning
Mounting 
Removal of Paraffin
Staining

Question 7

The first step in tissue preparation is FIXATION. What is the purpose of fixation?

Answer 7

Preserves the structural organization

Prevents digestion and protects from damage during the tissue preparation process

Ex: formalin

Question 8

The second step in tissue preparation is dehydration. What is the purpose of dehydration?

Answer 8

Removes the water which eases the penetration of the tissue by clearing agents

Ex: ethanol

Question 9

The third part of tissue preparation is clearing. What is the purpose for the Clearing process?

Answer 9

Prepares the tissue for infiltration

Ex: Xylene

Question 10

The fourth part of tissue preparation is Infiltration. What is the purpose of infiltration?

Answer 10

Prepares the cleared tissue for embedding

Ex: paraffin

Question 11

The fifth part of tissue preparation is embedding.what is the purpose of embedding?

Answer 11

Makes the tissue firm and prevents crushing during sectioning

Question 12

The sixth part of tisssue preparation is sectioning. What is the purpose of sectioning?

Answer 12

To allow light or electrons to penetrate the specimen and form an image

Question 13

The seventh part of tissue preparation is mounting. What is the purpose of mounting?

Answer 13

Eases handling and decreases damage to the specimen during examination

Usually uses a glass slide

Question 14

The 8th part of tissue preparation is the removal of paraffin or plastic. What is the purpose for the removal of paraffin or plastic?

Answer 14

Most stains are water soluble and therefore need to put water back into the tissue using xylene then ethanol then water

Question 15

The final part of tissue preparation is staining. What is the purpose for staining?

Answer 15

Makes the specimen visible

Ex: H and E are used most commonly and stain the tissue purple or pink

Question 16

Hematoxylin, Alcian blue and methylene blue stain what parts of the cell?

Answer 16

Stains basophilic parts of the cell: DNA, RNA, ribosomes

Question 17

Eosin and Orange G are acidic stains that stain what tissue parts?

Answer 17

Stains ACIDOPHILIC tissue parts such as mitochondria, secretory granules, collagen.

Acidic dyes have a high affinity for cytoplasm**

Question 18

Lipid soluble dyes such as Sudan black and oil red O rain what?

Answer 18

Stains long chain hydrocarbons, fats and oils

Question 19

Multicomponent histochemical reactions stain such as Periodic Acid Schiff (PAS) stain what?

Answer 19

Stains complex carbohydrates, glycogen

Question 20

Heavy metals such as lead citrate, Osmium tetroxide, and ruthenium red stains what?

Answer 20

Stains phospholipids, complex sugars

***used in EM work and produces images thata re black and white

Question 21

________ is the smallest distance that two objects can be seen as two objects

Answer 21

Resolution

Question 22

If you increase the refractive index what happens to the resolution?

Answer 22

The resolution decreases

Inverse relationship between refractive index (n) and Resolution (d)

Question 23

If increase the wavelength of light, what will happen to the resolving power?

Answer 23

The resolving power will increase

Direct proportional relationship between wavelength and resolving power

Question 24

What is magnification and how to you calculate it?

Answer 24

How large the image appears

Mag= objective lens (4X, 10X, 40X and 100X) times ocular lens (10X)