Lecture 1 Flashcards by George Magnus

What two chemical solvents that can be used to remove alcohol from a specimen?

Xylene and limonene

How well did you know this?

Not at all

Perfectly

In what four locations are neurons found?

Brain 2. Spinal Cord 3. Nerves 4. Ganglia

How well did you know this?

Not at all

Perfectly

How does smoking change the epithelial layer and surface modification of a trachea?

The epithelial layer transforms from being pseudostratified to stratified. The surface is modified from being ciliated to non-ciliated epithelium

How well did you know this?

Not at all

Perfectly

What are the two standard reference stains? What part of the cell is colored by each stain?

Hematoxylin and Eosin. Hematoxylin stains the Nuclei blue/purple; Eosin stains the cytoplasm and connective tissues pink/orange, and RBC bright red. Mnemonic: Henry (boy so blue/purple) loves Nancy (nuclei); Emily (girl so pink/orange) loves Chris (cytoplasm) and Christina (connective tissue)

How well did you know this?

Not at all

Perfectly

What are the four primary tissue classes?

Epithelial, Connective, Muscle, Nervous Mnemonic: Everyone Can Make Nachos (Credit: Rafael Brandao)

How well did you know this?

Not at all

Perfectly

What does embedding mean in histotechnology?

Suspending specimens in molds filled with liquid wax. Once the wax cools and solidifies the “embedded” specimens are removed from the molds and used for sectioning, the next step in histotechnology

How well did you know this?

Not at all

Perfectly

What glue is used to protect and preserve stained specimens during coverslipping?

Epoxy

How well did you know this?

Not at all

Perfectly

What are the seven (7) steps of histotechnology?

Grossing; Fixation 2. Processing 3. Embedding 4. Sectioning 5. Staining 6. Coverslipping 7. Diagnosis Mnemonic: George Fixed Patricia’s Engine So She Could Drive (Credit: Ben Baranes)

How well did you know this?

Not at all

Perfectly

What color is a raw image from an electron microscope (EM)?

Grayscale

How well did you know this?

Not at all

Perfectly

What type of blade is used to section specimens in an ultramicrotome?

A diamond blade

How well did you know this?

Not at all

Perfectly

How is a cross-section related to a longitudinal section?

A cross-section is perpendicular to the longitudinal section.

How well did you know this?

Not at all

Perfectly

What is the main difference between Histologists and Pathologists?

Histologists do not Diagnose

How well did you know this?

Not at all

Perfectly

In microscopy, what is visible light focused with? What are electrons focused with?

Glass lenses focus visible light. Magnets focus electrons

How well did you know this?

Not at all

Perfectly

What is the usual thickness of a section cut with a microtome?

4 to 5 microns (.004 mm to .005 mm)

How well did you know this?

Not at all

Perfectly

What are connective tissue cells suspended in?

Extracellular matrix (very abundantly, more matrix than cells)

How well did you know this?

Not at all

Perfectly

What is metaplasia?

Normal or abnormal change in tissue

How well did you know this?

Not at all

Perfectly

What characteristics of the extracellular matrix help to distinguish the four(4) tissue classes?

Proportion of water 2. Types of fibrous protein 3. Composition of ground substance

How well did you know this?

Not at all

Perfectly

What metal is used to stain sections for use in an electron microscope?

Lead

How well did you know this?

Not at all

Perfectly

What is the ground substance in the extra cellular matrix (ECM)?

Material between cells other than water and fibrous proteins

How well did you know this?

Not at all

Perfectly

What are the three surface modifications found on epithelial tissues?

Cilia 2. Microvilli 3. Keratinization

How well did you know this?

Not at all

Perfectly

What is an example of a specialized connective tissue?

Adipose tissue, hematopoietic tissue

What is the extracellular matrix?

Material between cells such as water, fibrous proteins and ground substance.

After sections are picked up on a microscope slide, what chemical solvent is used to remove the wax ribbon from the specimen?

Xylene

In what direction does the tracheal cilia sweep mucus?

Healthy tracheal cilia sweeps mucus up the trachea. Mucus sliding down the trachea could cause wheezing and coughing

Why are fixed specimens moved through a graded series of alcohols?

To remove water

Which type of nerve tissue cell is more abundant?

Glial cells

What are the four (4) different shapes of Epithelial tissue?

1. Squamous 2. Cuboidal 3. Columnar 4. Transitional

Which one of the four tissue types has the most ECM? Which one the least?

Connective tissue has the most. Epithelial the least

How does electron beam wavelength affect image resolution?

Shorter wavelength produces higher resolution images

What tool/machine is utilized to perform sectioning of specimens to be viewed under a light microscope?

The microtome

Electrons shoot _________ a specimen in a Transmission EM, while in a Scanning EM the electrons _______ off of the specimen.

thru; bounce

Approximately how many different cells types are in the body?

200

What are specimens embedded in for sectioning with an ultramicrotome?

Epoxy and/or other hard plastics

What are two examples of supporting connective tissue?

Cartilage, Bone

How do neurons receive, integrate, store and transmit information?

By releasing neurotransmitter chemicals from the tips of axons to be received by receptors on other cells

What is the initial step of gross processing (grossing)?

Cutting fresh specimens into small pieces to facilitate penetration of fixatives

How thick are sections when used in electron microscopes?

.01 micron or less

What does a continuously cut section resemble?

A ribbon

What is differentiation?

Unspecialized tissues, as in an embryo, change into specialized mature tissues

What is the difference between Hypertrophy and Hyperplasia?

Hypertrophy is the increase in size of cells. Hyperplasia is the increase in the number of cells

What is the average thickness of a Red Blood Cell? Average cell in the human body?

RBC is around 8 microns; Average cell is 60 to 100 microns

Which of the three muscle types is/are striated?

Skeletal and Cardiac. Smooth muscle is not striated

What are the two types of Nerve Tissue cells?

Neurons and glial cells

What is the major function of muscles?

To exert physical force

How does the layer of cells help to distinguish simple epithelial tissue from stratified epithelial tissue?

One layer of cells is simple epithelial tissue Two or more layers of cells is stratified epithelial tissue

What are the four types of connective tissues?

1. Embryonic CT 2. CT Proper 3. Specialized CT 4. Supporting CT

What is neoplasia?

Growth of abnormal tissue (hyperplasia) into a tumor. Can be both benign and malignant

Why is a section of specimen transferred to float in a warm water bath?

To smooth out wrinkles

What is the advantage of epithelial cells having microvilli?

Increased surface area

How do muscles respond to stimuli?

By contracting

What can xylene and/or limonene solvents be replaced with?

Mixtures of heated paraffin and other waxes

Why are aldehydes used to preserve a specimen?

Aldehydes (gluteraldehyde or formaldehyde) react with nitrogen in proteins to form stable bridges between adjacent proteins. These bridges stiffen a specimen for easier cutting.