Histology and Its Methods: Part I

Question 1

____________ is the study of tissues of the body and how these tissues are arranged to constitute organs

Answer 1

Histology

Question 2

What are two crucial understandings to the study of histology?

Answer 2

1. All living things are composed of cells and cell products
2. All diseases result from disorders in cellular function

Question 3

What are the basic levels of organization from smallest (atom) to largest (organism)?

Answer 3

Atom

Molecule

Cell

Tissue

Organ

Organ System

Organism

Question 4

What is a tissue?

Answer 4

A group of similar cells from the same origin that together carry out a specific function

Question 5

What is an organ?

Answer 5

A group of tissues that are formed by function

Question 6

What two interacting components become functionally specialized to give rise to tissues?

Answer 6

1. Cells
2. Extracellular matrices

Question 7

The ______________ _________ supports cells and contains fluid for transporting nutrients to cells and carrying wastes away from cells

Answer 7

Extracellular matrix

Question 8

What are the four basic tissue types?

Answer 8

1. Epithelium
2. Connective
3. Muscle
4. Nerve

Question 9

______________ tissue covers body surfaces, lines body cavities, and forms glands

Answer 9

Epithelial

Question 10

______________ tissue underlies or supports epithelial, muscle, and nervous tissue, both structurally and functionally

Answer 10

Connective

Question 11

What type of tissue is blood?

Answer 11

Connectivve

Question 12

_____________ tissue is composed of contractile cells, which underlie aspects of motility

Answer 12

Muscle

Question 13

_____________ tissue receives, integrates, and transmits information from outside and inside the body to control activities of the body

Answer 13

Nervous

Question 14

How many types of muscle tissue are there?

Answer 14

Three: muscle, cardiac, and smooth

Question 15

Of the three muscle tissues, which two are striated?

Answer 15

Muscle and cardiac

Question 16

Of all the tissue types, which is the least plastic, leaving it prone to damage and disorder?

Answer 16

Nervous

Question 17

There are two general methods for studying tissues: microscopy and ___________ ____________

Answer 17

Molecular techniques

Question 18

_____________ microscopy is based on the interaction of light and tissue components that’s often used to reveal and study tissue features. Types of this microscopy include bright-field, fluorescence, phase-contrast, confocal, polarizing, and differential interference

Answer 18

Light

Question 19

What is resolving power?

Answer 19

The smallest distance between two objects at which they can still be seen as separate objects; resolving power determines the quality of the image and is dependent upon the quality of objective lenses

Question 20

What is the resolving power of a light microscope?

Answer 20

0.2 µm

Question 21

The resolving power of a light microscope is around 0.2 micrometers, which allows us to see cellular components like a _____________ or cytoplasmic filament

Answer 21

Ribosome

Question 22

In ________________ microscopy, tissue sections are irradiated with UV light and the emission is in the visible portion of the spectrum, resulting in bright colors against a dark background

Answer 22

Fluorescence

Question 23

_________________ microscopy involves modified light microscopes that can be used to study unstained cells and tissue sections; images are generally transparent and colorless but can be used to view living, cultured cells

Answer 23

Phase-contrast

Question 24

The image is produced by what type of microscope?

Answer 24

Phase contrast

Question 25

The image is produced by what type of microscopy?

Answer 25

Differential interference

Question 26

In ________________ microscopy, light is optically aligned in the focal plane (i.e., confocal), resulting in improved resolution and specimen localization; however, the microscope must include a computer-driven mirror system to move the point of illumination across the specimen automatically and rapidly

Answer 26

Confocal

Question 27

\_\_\_\_\_\_\_\_\_\_\_\_\_ microscopy allows for recognition of structures made of highly organized molecules and produces images of materials with repetitive, periodic macromolecular structures - features without structure are not seen

Answer 27

Polarizing

Question 28

These images are taken with what type of microscopy?

Answer 28

Polarizing

Question 29

In ______________ microscopy, images result from the interaction of electrons and tissue components, and because the wavelength of an electron beam is much shorter, this type of microscopy allows for much better resolution

Answer 29

Electron

Question 30

In ________________ \_\_\_\_\_\_\_\_\_\_\_\_ microscope, an electron beam passes directly through the specimen, and heavy metal ions are often used for tissue preparation to improve contrast

Answer 30

Transmission electron

Question 31

What is the typical resolution of a transmission electron microscope?

Answer 31

Around 3 nm

Question 32

This image was taken via what type of microscopy?

Answer 32

Transmission electron microscopy

Question 33

In ___________________ \_\_\_\_\_\_\_\_\_ microscopy, electrons do not pass through the specimen; they simply scan the specimen, providing high resolution of surfaces, which is usually dried and spray-coated with a thin layer of heavy metal (i.e., gold)

Answer 33

Scanning electron

Question 34

From what type of microscope is this image produced?

Answer 34

Scanning electron

Question 35

\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ is a method of localizing newly synthesized macromolecules in cells or tissue sections by radioactively labeling metabolites to be incorporated into macromolecules in living cells

Answer 35

Autoradiography

Question 36

From what type of molecular technique is this image derived?

Answer 36

Autoradiography

Question 37

How can you tell the difference between autoradiography and electron microscopy images?

Answer 37

Autoradiography labels metabolic products whereas EM shows the cells themselves

Question 38

What types of information can autoradiography provide?

Answer 38

Which cells and how many cells are replicating DNA in preparation to divide as well as events, like where in the cell is a protein produced or secreted

Question 39

What are three benefits of *in vitro* and *in vivo* cell and tissue culture over other histological methods?

Answer 39

1. Molecular effects can be isolated on specific cell types 2. Cellular behavior can be directly observed under phase-contrast microscopy 3. Experimentation otherwise not possible with an intact organism can occur

Question 40

In ____________ \_\_\_\_\_\_\_\_\_\_\_, cells and tissues are grown in complex solutions of known composition with serum components or growth factors added

Answer 40

Cell and tissue culture

Question 41

In a ______________ cell culture, the cells are initially dispersed mechanically or enzymatically and plated sterilely upon which the cells adhere

Answer 41

Primary cell culture

Question 42

What is a cell line?

Answer 42

A permanent, immortalized line once isolated from normal or pathological tissue and maintained *in vitro*

Question 43

The process that promotes cell imortality in cell lines is called...?

Answer 43

Transformation

Question 44

In _____________ \_\_\_\_\_\_\_\_\_\_\_\_, the localization of cellular structures can be determined

Answer 44

Enzyme histochemistry

Question 45

Why are compounds or macromolecules tagged in enzyme histochemistry?

Answer 45

To detect and localize specific sugars, proteins, and nucleic acids

Question 46

Which histological method utilizes the highly specific interaction between antigen and antibodies?

Answer 46

Immunohistochemistry

Question 47

What's required for all immunohistochemical techniques?

Answer 47

Antibodies, which are produced against foreign antigens

Question 48

In ___________ immunohistochemistry, the antibody is made against the tissue of interest, tagged with a label, and placed with the tissue section on a slide; the labeled antibodies bind specifically to the antigens against which they were produced and can be visualized

Answer 48

Direct

Question 49

In ____________ immunohistochemistry, the primary antibody is made against the antigen of interest and applied to the tissue slide; then a secondary antibody is made against the primary antibodies and is labeled; the secondary antibody is applied to the tissue section and specifically binds the primary antibodies, indirectly labeling the protein of interest

Answer 49

Indirect

Question 50

Which is more sensitive and widely used? Direct or indirect immunohistochemistry?

Answer 50

Indirect

Question 51

Which histological method allows for the specific identification of DNA and RNA sequences?

Answer 51

Hybridization

Question 52

What is *in situ* hybridization?

Answer 52

Hybridization that occurs when a solution of nucleic acid is applied directly to cells and tissue sections