Intro to Histo Flashcards
two divisions of anatomy
macroscopic or gross anatomy; microscopic anatomy
___, ____, and ____ make up microscopic anatomy
cytology, histology, and organology
____ always reflects ____ or ____ always reflects _____
function; structure; physiology; anatomy
4 types of tissues
epithelial tissue (epithelium), muscle tissue, connective tissue, nervous tissue
the study of the microscopic anatomy (microanatomy) of cells and tissues of plants and animals
histology
levels of structural organization
chemical level (atoms, molecules, organelles); cellular level; tissue level; organ level; organ system level; organismal level
3 major techniques in histology
light microscopy, electron microscopy, atomic force microscopy
Specimens examined via transillumination (i.e., passing light through the specimen to facilitate observation)
light microscopy
electron microscopy provides ____ and ____
greater resolution; higher magnification
2 types of electron microscopy
transmission electron microscopy (TEM) and scanning electron microscopy (SEM)
uses a beam of electrons that passes through the specimen
transmission electron microscopy (TEM)
beam of electrons scans the surface of the specimen
scanning electron microscopy (SEM)
molecular and atomic resolution; DNA can be looked at with this mechanism; atom passes over surface and is deflected; does not require specimen to be in a vacuum
atomic force microscopy
Defined as how far two objects must be separated from one another so that they can be distinguished as two distinct objects
resolving power or resolution
resolution is dependent on:
- optical system
- wavelength of light source
- specimen thickness
- quality of fixation
- staining intensity
steps necessary for light microscopy
- acquisition of cells or tissues
- fixation
- processing
- embedding
- sectioning
- staining
procession involves ____, ____ and _____
dehydration, clearing, and infiltration
dehydration uses a ____ series of alcohol
graded
clearing uses a ____ substance
miscible
infiltration uses a _____
liquid embedding medium
problems with the typical histological technique used to prepare tissues to be observed with a light microscopic examination (i.e. with paraffin):
- time
- solvent dissolves lipids
- shrinkage of tissues
to combat time issue, ____ is used
cryostat
to combat solvent issue ____ is used in which first fixation is done with ____ and a second fixation is done with _____
double fixation; glutaraldehyde; osmium tetroxide
to combat shrinkage issue, embedding in ____ is used
resin
carry a net negative charge; bind with cationic cell/tissue components (i.e. those that carry a net positive charge)
acidic dyes
examples of acidic dyes
eosin, orange G, and acid fuchsin
acidic dyes stain ____ (or ____) tissues, those tissues with a high affinity for acid dyes; these tissues exhibit acidophilia)
acidophilic; eosinophilic
things that acidic dyes stain
mitochondria, secretory granules, collagen fibers (as well as other extracellular fibers), general cytoplasm, basement membrane
staining with acidic dyes is less _____; more substances within cells and the extracellular matrix exhibit ____ than _____
specific; acidophilia; basophilia
basic dyes carry a net ____ charge and bind with ____ cell/tissue components
positive; anionic (those that carry a net negative charge)
examples of basic dyes
toluidine blue, alcian, and methylene blue; hematoxylin, although not a basic dye, acts like one
basic dyes stain ____ tissue, i.e. those with a high affinity for basic dyes
basophilic (tissues exhibit basophilia)
basic dyes bind to :
-negative phosphate group on DNA and RNA (cell nucleus, nucleoli, RNA-rich portions of the cytoplasm); the carboxyl groups of proteins; sulfate groups of cartilage cartilage matrix (GAGs)
stains basophilic tissue, has a blue hue, has affinity to nuclei
hematoxylin (+)
stains acidophilic tissue, has a pink hue, has affinity to cytoplasm
eosin (-)
varieties of microscopes/microscopy
- bright field microscope/microscopy
- fluorescence microscope/microscopy
- bright field microscopy
- phase-contrast microscopy (unstained specimens used)
histochemistry and cytochemistry steps:
- section immersed in solution of enzyme’s substrate
- Enzyme acts on substrate
- Section put in contact with a marker compound
- Marker compound reacts w/ molecule produced by enzymatic action on substrate
- Final product (insoluble and visible by light or electron microscopy) precipitates over site
other histology techniques
histochemistry, cytochemistry, immunohistochemistry
the plasma membrane (plasmalemma) is composed of ____, ____, _____ and _____
phospholipids, cholesterol, proteins, and chains of oligosaccharides
Site where materials are exchanged between the cell and its environment; regulates the ion concentration of the cytoplasm; also recognition, regulatory, and interaction functions
plasma membrane
thickness of plasma membrane
7.5 to 10 nm in thickness (EM)
structure of plasma membrane
trilaminar (EM); fluid mosaic model
bulk uptake of material across plasma membrane into the cell; folding and fusion of membrane to form vesicles
endocytosis
“cell-eating”; phagosome; then fuses with lysosomes.
phagocytosis
“cell-drinking”; pinocytotic vesicle; then fuses with lysosomes.
pinocytosis
binding of the ligand to a receptor causes coated pits made of clathrin to form; pinches off to form a coated vesicle; fuses with endosomal compartment to form endosomes.
receptor-mediated endocytosis
release of material across plasma membrane into the extracellular space; involves vesicle fusing with plasma membrane and releasing its contents.
exocytosis
site of intracellular digestion and turnover of cellular components
lysosome
size of lysosomes
0.05 micrometers to 0.5 micrometers
lysosomes are membrane bound ____ that contain about 40 different _____
vesicles; hydrolytic enzymes
function of ribosomes
protein synthesis
size of ribosomes
20nm x 30 nm
Ribosoms are composed of two different-sized subunits; the subunits are composed of ____ and ______; can be found free within the _____ or attached to membrane of the _______
rRNA; proteins; cytoplasm; endoplasmic reticulum
Network of intercommunicating channels and sacs of membranes which enclose a space called a cisterna.
endoplasmic reticulum
ribosomes on the cytosolic side of the membrane; produces proteins for secretion
Rough endoplasmic reticulum (RER)
Regions of ER without ribosomes; cisternae are much more tubular; important in the production of phospholipids; abundant in cells that synthesize steroid hormones (i.e. steroid synthesis).
smooth endoplasmic reticulum (SER)
Completes post-translational modifications, packages, and sorts proteins synthesized in the RER.
golgi apparatus (golgi complex)
the golgi apparatus is composed of smooth membranous _____; has a ____ (i.e., entry) face and a _____ (i.e., exit) face
saccules; cis; trans
Membrane-enclosed organelles with enzymes arrays specialized for aerobic respiration and production of adenosine triphosphate (ATP)
mitochondria
size of mitochondria
0.5 micrometers-1.0 micrometers in diameter and 5 micrometers-10 micrometers in length
mitochondria have two membranes (i.e., inner and outer) and two compartments (i.e., _____); inner membrane folded to form _____ which project into matrix
matrix and intermembrane space; cristae
Formed at the Golgi apparatus; store product until it is released via exocytosis
secretory vesicles or granules
structure of secretory vesicles or granules
secretory product surrounded by membrane
degrade denatured and nonfunctional polypeptides
proteasomes
proteasomes are ____ proteins (i.e. no membrane); they have a ____ structure and are made of ____
cytoplasmic; cylindrical; 4 stacked rings
oxidizes various potentially toxic molecules as well as prescription drugs
peroxisomes
size of peroxisomes
0.5 micrometers in diameter
peroxisomes are ____ membrane-limited organelles
spherical
microtubules are fine tubular structures found in _____, _____, _____, _____ and ______
cytoplasmic matrix, centrioles, basal bodies, cilia, and flagella
microtubules are important for formation and maintenance of _____; cellular transport of ____ and ______; create repeated beating motion
cell shape; organelles; vesicles
size of microtubules
outer diameter of 24 nm and a dense wall 5 nm thick; hollow lumen
length of microtubules
variable; can be many micrometers in length
microtubules are composed of ____ and ____ tubulin molecules; they organize to form 13 parallel _______
alpha; beta; protofilaments
in cilia and flagella, the same core structure of microtubules is present:
axoneme
There is assembly of microtubules in a _____
9+2 pattern
Nine peripheral doublets have an outer arm of ____ which connects to next doublet; ATP-dependent interaction cause _____- get repeated beating movement
dynein; conformational changes
Allow for contractile activity within cells, including cell shape changes for endocytosis, exocytosis, and cell locomotion, moving cytoplasmic components, and cleavage during mitosis
microfilaments (actin filaments)
size of microfilaments (actin filaments)
5-9 nm
structure of microfilaments
composed of globular subunits organized into a double-stranded helix
intermediate filaments are very ____; they provide ____ and _____
stable; mechanical strength; stability
size of intermediate filaments
10-12 nm in diameter
structure of intermediate filaments
Protein subunits different in different cell types; rod-like subunit that organize into a cable-like structure
inclusions are cytoplasmic structures or deposits composed mainly of ______ or other substances; they are not considered _____
accumulated metabolites; organelles
examples of inclusions
lipid droplets, glycogen granules, and pigment deposits
main components of the nucleus
- nuclear envelope
- chromatin
- nucleolus
chromatin is the _____ material in a largely ____ state
chromosomal; uncoiled
2 types of chromatin
heterochromatin and euchromatin
heterochromatin are ____ in EM and _____ in light microscopy
course granules; basophilic clumps
euchromatin are less ____; they are ____ in EM and lightly ____ in light microscopy
coiled; fine granules; basophilic areas
the nucleolus is…
a spherical, basophilic structure present in nuclei of cells active in protein synthesis; lots of rRNA in this location
the process of cell suicide or programmed cell death
apoptosis
apoptosis leads to the production of ______ which undergo ____ by neighboring cells
small, membrane-enclosed apoptotic bodies; phagocytosis
resolving power of human eye
0.2 mm
resolving power of light microscope
0.2 micrometers
Resolving power of SEM
2.5 nm
resolving power of TEM
0.05 nm (theoretical)/ 1.0 nm (tissue section)
resolving power of atomic force microscopy
50.0 pm
hematoxylin only would stain ____
blue
eosin only would stain ____
pink
hematoxylin and eosin together would stain ____
purple
hematoxylin is a ___ dye that would stain ____ tissue
basic; basophilic
hematoxylin has a ____ hue and an affinity for _____
blue; nuclei
eosin is a ____ dye and would stain ____ tissue
acidic; acidophilic
eosin has a ____ hue and an affinity for _____
pink; cytoplasm
two parallel unit membranes separated by a narrow space; at sites where inner and outer membranes of the nuclear envelope fuse, nuclear pore complexes form; where regulation of the transport between the nucleus and cytoplasm takes place.
nuclear envelope
spherical, highly basophilic structure present in nuclei of cells active in protein synthesis; lots of rRNA in this location
nucleolus
