Bsf Block 1: Microscopy And Tissue Prep

Front 1

_________________ is synonymous with histology

Back 1

Microscopic anatomy

Front 2

The 4 steps of light microscope tissue preparation are...

Back 2

1. fixation
2. embedding
3. sectioning
4. staining

Front 3

Osmium tetraoxide is a

Back 3

common fixative for electron microscopy, fixes lipids

Front 4

The classic embedding medium for light microscopy is...

Back 4

paraffin

Front 5

_______________ is an embedding medium that can work only work on small tissue sections but allows thinner sections and yields far superior cell structure.

Back 5

Plastic resin

Front 6

What embedding medium is useful for large tissue sections?

Back 6

paraffin

Front 7

Tissue is sectioned on a cutting device called a

Back 7

microtome

Front 8

Plastic-embedded tissue can be cut down to _________. Paraffin-embedded tissue can be cut down to ___________.

Back 8

- 1 μm or less for electron microscopy

-10 μm, mainly for light microscopy

Front 9

Basic tissues are ____________, and thus stain with ________ dyes.

Back 9

-acidophilic

-acid

Front 10

Acidic tissues are ____________, and thus stain with ________ dyes.

Back 10

-basophilic

-basic

Front 11

What is the most common stain for light microscopy?

Back 11

H&E (hematoxylin and eosin)

Front 12

Hematoxylin is a (basic/acidic) dye and stains (acidic/basic) cell structures, such as the _________, in the ___________ color.

Back 12

-basic

-acidic

-nucleus

-blue/violet

Front 13

Hematoxylin would stain the nucleus of the cell in a ____________ color.

Back 13

blue/violet

Front 14

Hematoxylin stains ____________ cell structures because it is a ________ stain.

Back 14

-acidic

-basic

Front 15

Eosin is a _________ dye that stains the _______________, and other ________ structures, in the ________ color.

Back 15

-acidic

-cytoplasm/extracellular collagen

-basic

-red/pink

Front 16

Eosin is a(n) (basic/acidic) dye.

Back 16

acidic

Front 17

Structures that stain red/pink are termed...

Back 17

eosinophilic

Front 18

In electron microscopy, tissue is placed on ____________, instead of glass.

Back 18

copper grids

Front 19

A common method of preparing a rigid tissue block without the use of fixation or embedding is...

Back 19

rapid tissue freezing

Front 20

A microtome that sections a frozen block of tissue while keeping it frozen is called a ....

Back 20

cryotome

Front 21

Explain the advantages of rapidly frozen tissue. There are 3.

Back 21

-Histochemistry and cytochemistry can be used to study the well-preserved enzymatic activity
-Immunocytochemistry with antibodies for specific proteins can be used to study the well-preserved, natural protein conformations
-Retention of lipids--xylene in normally embedded tissue removes lipids. Freezing it bypasses embedding.

Front 22

A ___________ controls the diameter of the field illuminated by the light source.

Back 22

field diaphragm

Front 23

A ________ is placed above the field diaphragm and focuses light into a narrow beam.

Back 23

condenser

Front 24

The structure on which the glass slide sits is called the

Back 24

specimen stage

Front 25

What lens is immediately above the tissue sample?

Back 25

the objective lens

Front 26

The objective lens projects the image on the ________ lens, which further magnifies the image and projects it onto the user's retina.

Back 26

ocular lens

Front 27

What is the theoretical limit of resolution for a light microscope?

Back 27

0.1 to 0.2 μm

Front 28

What determines the resolution of a light microscope?

Back 28

the quality of the lenses

Front 29

With phase contrast microscopy, you can view _____________ because cellular and extracellular structures have different inherent refractive indexes; staining is not necessary.

Back 29

living tissue

Front 30

Differential interference optics......

Back 30

produce a three dimensional image of the specimen

Front 31

Dark field microscopy

Back 31

improves image contrast by shining a light obliquely--you see images that are reflected in a black background

Front 32

Which technique is useful in detecting crystals (eg, uric acid) and some micro-organisms?

Back 32

dark field microscopy

Front 33

______________ microscopy is used extensively in immunohistochemical procedures.

Back 33

fluorescent

Front 34

Three-dimensional reconstruction of tissue through "optical slices" can be done with ______ microscopy.

Back 34

confocal

Front 35

The two microscopy techniques which use fluoresence are....

Back 35

fluorescent and confocal

Front 36

An electron beam has a (shorter/longer) wavelength than a light beam, allowing a resolution of 1000x that of light microscopy.

Back 36

-much shorter

Front 37

What are the two types of electron microscopy?

Back 37

TEM and SEM

Front 38

With scanning electron microscopy, the surface of the specimen is coated with _____________. The electron beam is then scanned over the specimen and a detector measures the number of electrons reflected, producing striking 3d images.

Back 38

heavy metal

Front 39

What microscopy is responsible for that crazy looking red blood cell image?

Back 39

scanning electron microscopy (SEM)

Front 40

In ____________________, electron beams pass THROUGH specimen. This resolution is higher than other electron microscopy techniques and can go up to several hundreds of thousands in magnification.

Back 40

transmission electron microscopy (TEM)

Front 41

_____________ is the most helpful electron microscopy technique in examining subcellular biological structure.

Back 41

TEM

Front 42

The ___________ is like a light microscope turned upside down.

Back 42

TEM

Front 43

It is very (easy/hard) for an electron beam to penetrate matter. The same task is much (easier/harder) for a light beam.

Back 43

hard

light beams can penetrate matter much more easily...electron beam scatters to easily

Front 44

In transmission electron microscopy, tissue sections must be very...

Back 44

THIN