Histology Exam 1 (mod. 1-7)
all of the types of cartilage all look different and have different functions based on the type of --
ECM - in particular, the types of fibers they have
during the contracts, the what happens to the I band, Z band, and A band
I band shortens by a lot Z bands come closer together A bands remain the same length always
what are glycogen rosettes
In liver cells, cytoplasmic granules of glycogen group together to form rosettes, frequently in close proximity to smooth endoplasmic reticulum.
in columnar cells, the cytoplasm is...
MORE abundant usually (b/c tall cells with lots of room above the nucleus) and above the nucleus
appositional growth is only possible for cartilage that have a --
a perichondrium
TEM produces a
a picture in 2D
SEM produces a
a picture in 3D
the haversian canal is lined by
a single layer of cells called the osteogenic layer
in between acini there is
a small amount of CT
what is Periodic acid-Schiff (PAS)?
a specific stain that stains all sugar molecules, but especially mucous
because microtubules are polymerized from basal bodies, basal bodies are present...
at the base of each cilium (singular cilia) but in the cytoplasm
basal part of the cell is located
at the bottom of the cell (for epithelial cells, this is near the basement membrane)
what is the core of a microtubule called
axoneme
why is the I band less dark?
b/c actin filaments are so thin we don't see them individually
why does ground substance often appear clear?
b/c it is removed by the solvents we used in the embedding step of tissue processing
mesenchymal CT is found...
b/t the organs in the embryo
a -- pattern form in -- fibers, but does not form in -- fibers
banding pattern forms in collagen fibers but not in elastic fibers
microtubules are polymerized from --
basal bodies
the basement membrane is made up of
basal lamina and reticular lamina
what is histochemistry based on?
based on chemical affinities between the components of the cells and the dyes used
basement membrane is the term used at -- while basal lamina is the term used at --
basement membrane = term used at light level basal lamina = term used at EM level
we typically use 2 types of dyes in general, which are
basic dyes and acidic dyes
are chondroblasts eosinophilic or basophilic
basophilic
because they have so much RER, osteoblasts are extremely
basophilic
calcified cartilage is --(philicity)?
basophilic
is the nucleus acidophilic or basophilic
basophilic
purple coloring in H&E is
basophilic
serous glands stain --
basophilic
the different GAGs in the cartilage ground substance is -- (philicity)?
basophilic
when something is stained with hematoxylin it is called
basophilic
what is the philicity of territorial ECM? why?
basophilic b/c it has less collagen and more glycosaminoglycans
in a cell, the basophilic elements are --(adj) and in particular they are
basophilic elements are acidic and in particular they are the nucleic acids
basic dyes stain molecules, elements, and structures in the cells that are -- elements, meaning...
basophilic elements, meaning they are attracted to the basic dyes
what shape/appearance do mitochondira typically take on
bean shaped with cristae that are perpendicular to the long axis of mitochondria - but this is not always the case
why would there be fibroblasts among the adipocytes
because each adipocyte is also surrounded by reticular fibers (which fibroblasts synthesize)
why is the BM so thick?
because in some parts of the body, the BMs b/t cells will fuse, making the BM thicker
why do we use osmium tetroxide as a heavy metal?
because it has an affinity for the heads in the phospholipid bilayer of the membrane
why is non-lamellar bone also called primary bone sometimes
because it is newly formed bone - it's the bone that forms before it gets mineralized
why might the cells of brown adipose tissue have lots of mitochondria
because it's involved with heat production
hematoxylin stains nuclei what color
blue according to a lab video we watched (produced by another company)
what is the color of hyaline cartilage
bluish, opalescent color (glass looking ends of bones in chicken)
what is the origin of mast cells
bone marrow stem cells
both the osteons and the neurovascular bundles -- in tunnels that are...
both branch into tunnels that are perpendicular to the long axis of the bones and known as volkmann's canals
canaliculi can be very -- which means the filopodia can be very --> this is how osteocytes connected with different lamellae --
both can be very long; how osteocytes connected with dif. lamellae communicate
the liver is made up of what kind of epithelium
both covering and glandular - the middle is glandular and the outer parts/linings are covering
all of the characteristics I described above for multicellular glands applies to
both endocrine and exocrine glands
there are acini in what types of glands
both serous and mucous
if the secretory portion divides it is called
branched
microvili can also be referred to as the -- --
brush border or striated (brush) border
the nucleus is limited by a -- so it has....
by a nuclear envelope - so it has 2 membranes
how is the stain differentiated ultimately?
by placing the sections in acid-alcohol until the structure you want to see is stained and all other parts of the tissue are colorless
what is a cementing line?
calcified ground substance in between the osteons
normally, elastic cartilage does not --? related to ossification
calcify
removing the inorganic material on the other hand would entail removing the
calcium and phosphorus
the peri space is how the -- and -- circulate
calcium and phosphorus
the inorganic part of the matrix forms when..
calcium and phosphorus deposit hydroxyapatite crystals on the collagen type 1 fibers
in the middle of the nucleus, there is a structure called the -- and its job is to...
called the nucleolus - job is to assemble the ribosomes
in vitro, fibroblasts can act like -- and remain --
can act like stem cells and remain multi-potential
type 1 can be different -- and associate in different --
can be dif. sizes and associate in dif. sized bundles
in terms of elasticity, the ECM in cartilage can be firm to allow for -- or could be elastic or could bear...
can be firm to allow for compression or could be elastic or can bear mechanical stress - each of these 3 functions corresponds to a different type of cartilage
the nucleus can be -- and in the -- of the cell, but we also see that most cells are not....
can be round and in the center of the cell, but most cells are not round and neither is their nucleus nor is it centered
elastic fibers can -- or can form -- (regarding how they are organized)
can branch or can form sheets
healthy hyaline cartilage can -- which is normal during ossification
can calcify
sometimes the chemical fixative can cause -- as an artefact
can cause clumping of proteins
mitochondria can come in different -- and cristae may be...
can come in different shapes and cristae may be tightly packed or tubular
lamellar bone can either be -- or -- but both have a --
can either be cancellous bone or compact bone, but both have a lamellated matrix
epithelial cells can have -- specializations - what are the 3 types?
can have luminal surface specializations - 3 types are microvili, cilia/flagella, and stereocilia
immunocytochemistry can indicate -- and it is called "immuno" because..
can indicate activities called immuno because it's antibody based and we're interested in a specific antigen
elastic fibers can -- and -- so they are found in places that need elasticity like the -- or in the --
can stretch and recoil so they are found in places that need elasticity like the aorta or in the dermis
in a cross-section of epithelium we cannot see the -- which makes the epithelium difficult to ID in cross-sections
can't see a lumen in the epithelium in a cross-section
the endosteum also lines both types of --
canals, which are the haversian canals and the volksmann's canals
there are 2 major types of bone, which are
cancellous bone compact bone
without calcium, actin and myosin...
cannot interact
once the cells become hypertrophic and switch to synthesizing a dif. type of cartilage, they cannot maintain the -- anymore so the cartilage will --
cannot maintain the cartilaginous matrix anymore so the cartilage will calcify
ex. of dense irregular CT
capsule (of what?? lol)
the outer fibrous layer of the periosteum is the layer that
carries the nerves, BVs, and fibers etc
blood vessels carry -- cells and -- as they penetrate the matrix. upon penetration, the -- start...
carry osteogenic cells and osteoclasts as they penetrate the matrix. upon penetration, the osteoclasts start resorbing the calcified matrix
all of the zones we discuss refer to -- rather than bone
cartilage
different types of college fibers are in different types of
cartilage
using hyaline cartilage as a template works really well because... and it's important for the fetus because...
cartilage can grow really fast, both in bulk and length and this allows the fetus to grow - the cartilage is able to grow appositionally or interstitially
appositional growth means that the cart will -- and allow growth in --
cartilage will build up and will allow growth in girth (width)
if the limit of the cells CANNOT be readily seen it means that the cell has formed -- meaning it...
cell has formed interdigitations, meaning it folds and because of that, from far away, we don't see a clear limit between the cells
inside of one fascicle you see many --
cells
what are the components of CT
cells extracellular matrix
because it is CT, bone is made up of -- and --
cells and ECM
because cartilage is CT that means it is made up of
cells and an ECM
how does the nucleus appear in mast cells?
cells show a CENTRAL, spherical nucleus with a conspicuous nucleolus
an acinus is formed by
cells that almost look triangular (like slices of a pizza, where the pizza is the acinus)
when the outer fibrous layer of the periosteum has typical fibroblasts, the inner part of the periosteum has...
cells that can differentiate into the cells that form the osteoid
chondrogenic cells are able to differentiate into
cells that make the matrix for the cartilage
what are the component of cartilage
cells, matrix, and perichondrium
where there is bone attachment, you will often see a
cementing line so learn to associate this with fibrocartilage since fibrocartilage is commonly found there
fibroblasts might differentiate into other types of cells like
chondroblasts
anywhere there's anticipated excessive tensile forces and you think they're fibroblasts, they're probably actually
chondrocytes
in the zone of calcification, cells become-- and they die and when they die they can no longer maintain the -- so it will --.
chondrocytes become hypertrophic and they die and when they die they can no longer maintain the cartilaginous matrix so it will calcify
what kind of tissue is typical with fibroblasts and collagen?
dense irregular CT
each fascicle is limited by
dense irregular CT more or less but it depends on the size - this is known as the perimysium
collagen type 1 fibers are associated with -- tissue
dense irregular tissue
reticular fibers can be described as -- because they stain with silver --
described as argyrophylic bc they stain with silver salts
transitional epithelium can be described as -- since it is only found in the
described as uroepithelial since it's only found in the urinary system
at the EM level, we see anchoring junctions as a
desmosome
SER is involved with (3 functions)?
detoxification synthesis of steroids storing calcium in muscle cells
special stains are absolutely critical for the diagnosis of -- and -- diseases. this is truly the ONLY way to make this diagnosis
diagnosis of bacterial and fungal diseases
as the fetus/cartilage template grows, the cells in the center of the bone begin to -- at some point and that's when they become hypertrophic and start synthesizing a dif. type of cartilage
die
as the fetus/cartilaginous model grows, the cells in the center of the bone will -- at one point
die
in holocrine glands, cells that produce the product...
die and when they die, they discharge the product
with merocrine secretion, the whole cell --
dies
osteoblasts differentiate into -- but these are not -- osteoblasts
diff. into osteocytes but osteocytes are not quiescent osteoblasts
different types of collagen fibers can be stained with
differential stains - really useful in lab
euchromatin
diffused chromatin - transcriptionally active
if CE is not vascularized that means it receives its O2 and nutrients based on
diffusion from underneath since blood vessels do run through CT
each muscle is organized as a bunch of
fascicles
if it is a large muscle, there will be many -- but if it is a small muscle there will be less
fascicles
adipocytes are -- cells
fat cells
collagen is synthesized by
fibroblasts
it is really hard to differentiate chondrogenic cells from --
fibroblasts
it would be easy to confuse the nuclei of unilocular adipose tissue cells with the nuclei of -- among adipocytes
fibroblasts
what is the most abundant cell type in the CT
fibroblasts
when they are active, fibroblasts are referred to as
fibroblasts
what kind of cells synthesize reticular fibers (or type 3 fibers)
fibroblasts - can be called reticular cells but NOT reticulocytes
because the endomysium has reticular fibers it also must have..
fibroblasts and capillaries
the nuclei of all these cells in loose CT are probably mostly nuclei of -- but could also be...
fibroblasts but could also be transient depending on the health status of the individual
elastic fibers are synthesized by?
fibroblasts, but also by smooth muscle cells to some extent like in the case of blood vessels
mesenchyme differentiates into...
fibroblasts, chondrocytes, osteocytes, or blood cells
which type of cartilage is the one that can bear mechanical stress?
fibrocartilage
when they are quiescent/inactive, the cells are referred to as
fibrocytes (quiescent fibroblasts)
elastic cartilage has a -- appearance
fibrotic
the outer layer of the perichondrium contains
fibrous tissue with type I collagen fibers
microfilaments
fine strands of the protein actin - very very thin
in hyaline cartilage, the ECM is
firm
what are the steps of preparation of material for histology? (6 steps)
fixation dehydration/clearing embedding (paraffin/resin) sectioning staining mounting
resident cells are -- in CT all of the time and are all derived from...
fixed in CT all of the time and are all derived from undifferentiated mesenchymal cells during development in the embryo (so basically like stem cells)
fibroblasts rarely divide unless the tissue is involved in
fixing damage like scar tissue for example
squamous cells tend to be -- (shape). describe the shape of the nucleus and cytoplasm
flat cells. the nucleus is elongated and very flat. cytoplasm is extremely thin and spread out so the nucleus bulges out like a fried egg
what is the shape of osteoprogenitor cells
flat, spindle-shaped
what's an example of a situation where frozen sectioning would be used
for biopsy diagnosis
sometimes macrophages can fuse and form
foreign-body giant cells that are sometimes multi-nucleated
once the mold with the specimen/paraffin in it cools, it'll form a -- that can be
form a block that can be sectioned using a microtome
bone can be formed via -- ossification, and this is the process that occurs in flat bones like..
formed via intramembranous ossification. happens in flat bones like the skull, shoulder blades, clavicle etc and it happens in the bone collar on long bones
you will find reticular fibers forming the -- of many --
forming the stroma of many glands/lymphoid organs
hyaline forms the -- cartilage in joints at the end of the --
forms the articular cartilage in joints at the end of the ribs/sternum
examples of where you'd find fibrocartilage in the body
found b/t tendons and ligaments (like attaching onto bones) found in pubic symphysis in meniscus of the knee in intervertebral discs
type I collagen fibers are found in -- and are the most -- type
found in CT proper and are the most abundant type
mature CT is found in the -- and is subdivided into 2 categories, which are
found in the adult and is subdivided into connective tissue proper and specialized CTs
brown adipose tissue gets its pigment from -- which are naturally occurring...
from lipochromes - a naturally occurring, fat-soluble pigment
EO occurs from the time we are a -- to the time we are a few years into --. this is how we...
from time we are a fetus to a few years into adulthood. this is how we grow after we're born
parenchyma is the -- material of a gland
functional material
in the zone of calcification, the lacunae..
fuse and the cells die - they are invaded by osteogenic cells
myoblasts -- end to end and that's why they become --
fuse end to end and that's why they become multi-nucleated
shape of fibroblasts
fusiform - cell is pointy on both sides
-- form at the ends to the filopodia
gap junctions
the fibroblasts will give rise to -- according to their levels of activity, while chondrocytes, osteocytes, or blood cells give rise to
give rise to CT proper last 3 cell types give rise to specialized CTs
when you have things that are PAS+ it shows you probably have more -- tissue
glandular
at the EM level, the SER looks much more
globular and irregular than RER
the ground substance allows the cells/fibers to...
glue together to form a connective tissue
the trabeculae go in certain -- depending on the -- placed upon the bone
go in certain directions depending on the mechanical loads placed upon the bone
the max resolution in a TEM is -- so we can see things like
goes up to 1 nm so can see things like the phospholipid bilayer
you can also use gold beads of -- so you can tag different things on...
gold beads of different sizes so you can tag different things on the same structure
what stain is usually used for bacteria? what's an exception to this?
gram stain - H pylori is an exception (other stains than just gram stain can be used on this bacteria)
mast cells produce lots of...
granules that contain heparin, histamines, etc (things we fight when we have allergies)
a goblet cell is a great example of a -- cell because the product droplets push...
great example of a polarized cell because the product droplets push down the nucleus to the base of the cell
basic dyes are usually what color
green/blue/ purple
you are able to se the canaliculi really well in
ground bone
when staining CT with H&E, the ground substance appears -- while the fibers appear --
ground substance = clear fibers = eosinophilic (so pinkish red)
the extracellular matrix in CT is made up of
ground substance and fibers
glycosaminoglycans (GAGs)
groups of sugar molecules
in the zone of maturation/hypertrophic chondrocytes, the lacunae and cell --
grow
interstitial growth allows for growth in --
growth in length (horizontal growth - grows side to side, spreading in either direction)
What is a hemidesmosome?
half of a desmosome that occurs at the base of epithelial cells that attach the epithelium to the underlying connective tissue
at the light level, college has -- aspects and is very -- (philicity) material
has wavy aspects at light level and is very eosinophilic
fibroblasts have -- stages. one where they are -- and one where they are --
have 2 stages. one where they're actively synthesizing ECM and one where they are quiescent
all epithelia have a -- membrane, except it's actually...
have a basement membrane except it's actually NOT a membrane
the cells of brown adipose tissue have lots of --, meaning the nucleus...
have lots of small droplets of lipids within a single cell, meaning the nucleus won't be pushed against the membrane so it will be readily visible
volkmann's canals are perpendicular to --
haversian canals
in the dense parts of the bones (so where compact bone is located) lamellae are organized as
haversian systems, also called osteons
what do we use instead of dyes when doing TEM
heavy metals - particularly osmium tetroxide
cartilage helps form the -- skeleton because it serves as the...
helps form the embryonic skeleton because it serves as the template for endochondral ossification (how the skeleton becomes ossified)
bone marrow is a -- organ
hematopoietic organ (i think that just means it makes blood cells)
in terms of mix, elastic ECM is --
heterogeneous
is the perichondrium vascularized? innervated?
highly vascularized and also innervated
3 different types of exocrine glands utilize 3 different mechanisms of secretion - the 3 types of exocrine glands are?
holocrine merocrine apocrine
since bone stores calcium and phosphorus, it must have a function in
homeostasis
the cells of skeletal muscle are very -- they are long bands of cells
homogeneous
in some sections of hyaline cartilage, we see that the matrix does not stain --
homogeneously
EO explains how the cartilaginous skeleton becomes ossified, but doesn't explain..
how long bones grow - how we go from fetus to adult
the classification of the 2 types of adipose tissue depends on
how many droplets of lipids there are in each adipocyte
masson's trichrome is critical for determining how much -- tissue is present, which indicates...
how much fibrous tissue is present, which indicates the relative degree of cirrhosis
in elastic cartilage, when it is stained with eosin, it is difficult to differentiate it from
hyaline
one type of cartilage where water is included in the ground substance is
hyaline
what is the most widespread cartilage in the body
hyaline
which type of cartilage is the cartilage that can withstand compression
hyaline
there are 3 types of cartilage, which are
hyaline elastic fibrocartilage
type 2 collagen fibers are found in
hyaline, elastic cartilage, and cornea
the only way cartilage without a perichondrium can grow is via
interstitial growth
transverse tubules (T-tubules)
invaginations (dips down into the inside of the cell and forms a little tube and continues on to form another invagination) of the sarcolemma (PM) - like long, thin pits
the results of staining can vary depending on.... (8 things)
quality of solutions type of tissue protocols of prior steps quality pH salinity of water used in the lab reagents used time of exposition in every solution
epithelium lines the -- (not a big body cavity or organ) and it is always -- epithelium
lines the BVs - always simple squamous epithelium
Kupffer cells
liver macrophages - always there since they're resident cells
special staining is critical in the diagnosis of most -- specimens
liver specimens
bone is a --tissue that is -- remodeled
living tissue that is constantly remodeled
once the CT separates the organ into major lobes, it continues to invade the organ, separating even the major lobes into
lobules
describe the nuclei of skeletal muscle cells
located at the periphery of the cells - it is NOT centralized
stereocilia are -- in the body. they are found...
rare in the body - found in the epididymis in males and in the inner ear
satellite cells do not help regenerate muscle in --
really big injuries
the periosteum is very close to the -- of the bone and so once in a while it will...
really close to the matrix of the bone so once in a while it will insert into the bone matrix and form what are known as sharpey's fibers
mesenchymal cells are -- after birth
really depleted after birth
in particular, what do anchoring junctions really stabilize?
really stabilize the epithelium
the cells involved in pseudostratified columnar epithelium are typically what type of cells? (not shape or something we've mentioned in the last 327 cards lol)
regenerative cells
size of chondrocytes?
relatively large
remember that both types of canals are also lined by the endosteum (and thus have osteoprogenitor cells) and that's important for
remodeling
in holocrine glands, the cells will constantly be
renewed
uni adipose tissue progressively replaces -- and -- as we age
replaces bone marrow and thymus and glands as we age
fibrocartilage is the type of cartilage that -- other cartilage when --
replaces other cartilage when injured
EO progressively replaces the --, but it will remain at the -- or in between the -- and -- of the bone
replaces the cartilage, but it remains at the end of in between the epiphysis and diaphysis of the bone and maybe even the metaphysis depending on the case
the smooth ER in skeletal muscle cells serves as a
reservoir for calcium
what kind of cell is fixed in CT all the time?
resident cells
there are two main populations of cells in CT, which are
resident cells and transient cells
the thickness of the PM is way smaller than the power of... thus we must use a -- to visualize the membrane
resolution of the compound microscope - must use an electron microscope to visualize the PM
in IO, you may also see osteoclasts that come and..
resorb old bones -- remodeling and then new bones reform via IO
the endomysium contains what kind of fibers
reticular
reticular fibers and PAS staining?
reticular fibers are PAS+
type 3 fibers are also known as -- fibers that form --
reticular fibers that form reticular tissue
when you don't recover your -- well you can also create foldings
ribbon
with paraffin, you obtain a --
ribbon - idek what this means, I just wrote it down
SER does not have
ribosomes
hematoxylin also stains -- because they have a lot of nucleic acids as well
ribosomes
the rough ER looks rough due to the presence of
ribosomes on its surface
in between staining sessions, you do what to the slides
rinse them in tap water
acinar shape is
round
shape of chondrocytes?
round
animal cells can come in various shapes they can be...
round, elongated, or can be an extension of the plasma membrane - can be large or small
cilia and flagella have the same -- they are anchored into the...
same structure - anchored into the cytoplasm
the PM of skeletal muscle cells is called the
sarcolemma
the cytoplasm of skeletal muscle cells is called the
sarcoplasm
ER in the skeletal muscle cell is called the
sarcoplasmic reticulum
the stroma of multicellular glands is like the
scaffolding of the functional unit - surrounds acini and i think it contains the CT
skeletal muscle looks like
long tubes
in what kind of section do you see the striations characteristic of skeletal muscle cells
longitudinal
what is a haversian canal?
longitudinal channel to the long axis of the bones - see them in cross-section as the center of each osteon
there are -- types of electron microscopes
scanning electron microscope (SEM) transmission electron microscope (TEM)
stereocilia look like -- but they're actually much more like
look like cilia but behave much more like microvili - they are NOT cilia
macula occludens has a -- appearance
scattered
if your knife/razor blade isn't perfect, we can get
scratch marks or sometimes stripes in the tissue = knife mark errors
ex. of a holocrine gland
sebaceous glands on skin that're involved in acne (secrete sebum in this case)
what is the function of osteoblasts
secrete osteoid
glands only have one job and that is to
secrete things
what is the specific function of glandular epithelium
secretion
the endomysium is made up of what kind of tissue - why is it important?
loose CT - that's diff from the epimysium or the perimysium that are made up of dense irregular CT
two types of CT proper
loose CT and dense CT
sometimes adipose tissue is considered it's own tissue or sometimes it and its two types are considered as subdivisions of
loose CT proper
mucous is very PAS+ because it has
lots of carbs (sugars)
abundance of fibers in dense CT?
lots of fibers
when golgi are present, the consequences of staining include the formation of a white area surrounding the nucleus like a halo and that indicates the presence of...
lots of membrane because membranes don't pick up the stain
in certain low -- concentrations, osteoprogenitor cells may even become --
low O2 conditions = could become chondroblasts
apical part of the cell is also known as the -- side of the cell and it's located...
luminal side of the cell - located at the top of the cell
where is the reticular tissue located?
lymphoid tissues and many glands
under an EM microscope, lipids appear as .. so in this case when we're identifying ORGANELLES don't get them mixed up with --. easy way to tell the difference is...
lysosomes - lysosomes will have a membrane, lipids will not
what are the two types of anchoring junctions
macula and zonula adherens
rosettes are made of -- and typically look like little --
made of glycogen, typically look like little asterisks
elastic fibers are made up of -- while collagen fibers are made up of
made up of the protein elastin, while collagen fibers are made up of the protein collagen - these two proteins are very different
osteoclasts first make contact with the -- matrix and create a -- environment that will..
make contact with the calcified matrix and create an acidic env. that will degrade the matrix = osteoclasts form a concavity in the matrix
ex. of apocrine gland
mammary glands
dense CT has many many more -- arranged in --
many many more fibers arranged in bundles
there are many types of -- which are bigger than -- but smaller than --
many types of intermediate filaments - bigger than microfilaments, but smaller than microtubules
type 1 collagen fibers stain differentially with what stain specifically
masson's trichrome
which staining technique in particular takes a long time to complete
masson's trichrome
2 examples of resident cells
mast cells macrophages
zonula occludens and macula occludens prevent and discriminate...
material that goes through
other than the collagen type 1 fibers, there is almost no other -- in fibrocartilage
matrix in fibrocartilage - there is almost NO matrix
osteocytes are the -- bone cells
mature
lamellar bone can also be called
mature bone or secondary bone
in LM, the max level of resolution is -- so we only see..
max resolution is .2 micrometers so we'll only see large structures like the nucleus probably
the type of CT that makes up the periosteum, may be -- or -- depending on the -- of the bone
may be dense irregular or loose CT depending on the size of the bone. large = dense irregular, small bone = could be loose CT
uni adipose may form large -- but it is also found in....
may form large aggregates, but it is also found in small clusters b/t other tissues
osteocytes in the peri space are consisdered to be....
mechanosensory cells that will regulate the composition of the bone matrix
the cytoplasm contains inclusions that are not
membrane bound
at the EM level we can see the RER as a network of...
membrane dotted by ribosomes all over with a lumen inside
how are microvili formed
membrane folding
PAS works really well when trying to visualize ... on kidneys. it specifically shows if the membranes are...
membranes with detail on kidneys - shows if the membranes are continuous? thick? thin? have spikes?
what is the most common type of exocrine gland
merocrine glands
at the start of intramembranous ossification, -- cells will be present
mesenchymal
wharton's jelly contains lots of
mesenchymal cells that are true stem cells
although there are 2 subdivisions of mature CT, all CT has a common embryonic origin, which is the
mesenchyme
the granules produced by mast cells, when stained, show that they are
metachromatic
example of a random stain also used in LM
methyl green
both -- and -- have something to do with motion, but not -- filaments
microfilaments and microtubules have to do with motion, but not intermediate filaments
what are the 3 types of filaments
microfilaments, intermediate filaments, microtubules
on the surface of goblet cells there are very few
microvili
because of the way a knife sections tissue, it appears that not all -- are connected to the cytoplasm but they are
microvilli
the primary ossification center ALWAYS occurs in the
middle of the diaphysis
in IO, the matrix gets -- after it surrounds the osteoblasts and they differentiate into osteocytes
mineralized
in between myofibrils there are things like..
mitochondra, cytoplasm, glycogen etc
cells of brown adipose tissue have lots of
mitochondria
there are lots of what kind of organelle in skeletal muscle cells
mitochondria
an example of how epi cells are polarized is with what organelle in particular and why?
mitochondria - because sometimes mitochondria are more abundant closer to where cilia are anchored
cardiac muscle cells are --nucleated
mono-nucleated
precursor of macrophages
monocytes
a macrophage is a -- -- system
mononuclear phagocyte system - remember they only have one nucleus when trying to ID them
like macrophages, osteoclasts work as a -- -- system
mononuclear-phagocyte system
in compact bone, the osteoclasts are more --like where -- will enter the bone and carry more cells to..
more tunnel-like, where BVs will enter the bone and carry more cells to make more bones = process of remodeling
what does mounting entail and when does it occur?
mounting is just putting the coverslip over the section; you mount after you stain
skeletal muscle is the type of muscle that allows us to
move
cartilage helps facilitate bone...
movement like the joint
abundance of ground substance in dense CT?
much less ground substance - there is almost none in dense regular CT)
length of cilia compared to microvili
much much longer than microvili - they're long in general
what is the product a goblet cell produces?
mucinogen - product is in droplets
there are two main types of secretions exocrine glands produce - those are...
mucous (Adjective) serous
mucous glands stain -- while serous glands stain -- in H&E
mucous = stains very light serous = stains very dark
bone matrix is partially -- and partially --
partially organic and partially inorganic
although healthy hyaline cartilage can calcify, calcification can also be a
pathological status as we age --> joint pain as you age (Reduced mobility)
hyaline cartilage is surrounded by a -- except in the case of the growth plate and the articular joint
perichondrium
the epimysium invests into the -- and that's how it's made
perimysium
what is the job of macrophages?
phagocytosis - pathogens or debris thus macrophages are found in abundance where there's a lot of junk in the body
what is the PM made up of?
phospholipid bilayer several other molecules integrated into that membrane
what are some examples of inclusions
pigment rosettes lipid droplets
osteoclasts are very -- cells because the -- part of the cell is not the same as the other parts of the cell such as..
polarized b/c the apical part of the cell isn't the same as the other parts of the cell such as the clear area where there's more actin
whether they're squamous, cuboidal, or columnar all of these epithelial cells will be
polyhedral
how does interstitial growth work?
pre-existing chondrocytes in the matrix divide mitotically to produce daughter cells that secrete matrix. as they secrete matrix, they push one another away and the cartilage grows in the directions they are pushed
chondrogenic cells are the precursors to -- which are cells that...
precursors to chondroblasts, which are the cells that synthesize the matrix
most of the time when you see lumen, it indicates the presence of -- since it...
presence of covering epithelium since it separates the inside env. from the outside env. or the tissues (separates tissues that is)
when monocytes receive a signal that they are needed, they do a process of -- in between the endothelial cells that is known as
process of crawling in between the endothelial cells that is known as diapedesis
the bone can form in 2 ways - the process of ossification is -- but the environment is --
process of ossification is the same, but the environment is different
histochemistry is used to visualize certain products that are in cells and tissues. it can be described as both -- and --.
products that are in cells and tissues - can be both qualitative and quantitative
ossification describes the process in which the fetal skeleton is
progressively ossified
what are the functions of bone?
protection support locomotion holds the bone marrow storage for Ca/P
why are cells producing serous secretions so dark?
proteins are made by ribosomes in the RER most of the time, which is very basophilic, so cells actively producing polypeptides are very basophilic
when GAGs attach onto a core protein they form
proteoglycans
the ground substance of cartilage is made up of
proteoglycans different GAGs glycoproteins water
with masson's trichrome, each color stains a different part of the cells --> what are these respective parts
purple = nucleic (material?) pink = cytoplasm blue or green = collagen type I
with H and E - the most classic combination of an acidic and a basic dye - the colors are...
purple and pink
the lipid droplet in unilocular adipose tissue is so big that it does what to the cell?
pushed the nucleus towards the membrane of the cell such that the nucleus becomes very flattened
mast cells are -- cells, which are part of the body's first..
sentinel cells, which are part of the body's first line of defense
in mixed glands, there can be demi-lunes, which are
serous cells that form a crescent shape and cap mucous acini
why do you think serous glands are basophilic
serous glands produce proteins like enzymes
the --, --, and -- of the nucleus are important characteristics in different tissues/organs
shape size position
the perichondrium is a CT -- , which is a -- CT layer that...
sheath, which is a dense irregular CT layer that surrounds some of the cartilage
the brush border's is fairly (length)
short - microvili are very short
elastic cartilage supports -- like the outer ear
supports soft tissue like the outer ear - you can pinch it and move it around and it'll go back to it's original position/formation
origin of glandular epithelium (GE)
surface epithelium
both types of glands originate from
surface epithelium - both exocrine and endocrine glands
what is an example of surface epithelial tissue being the origin of glandular epithelial tissue?
surface is the upper part of the skin and the gland it grows in to is the sweat glands OR the surface is the lining of the gut and the exocrine glands are the liver/pancreas --> product goes to the lumen of the gut
covering epithelium lines...
surfaces - top layer of skin, lining of any cavities in the body
the perimysium further invests into the fascicle and surrounds each -- and it is now called the --
surrounds each muscle cell (fibers) and it is now called the endomysium
what is the largest component of proteins
the cytoskeleton
A band
the dark band b/c it has BOTH actin and myosin
it is not really possible to tell -- apart in a lab
the dif types of exocrine glands in a lab like in real life
what factors define the cartilage and its function?
the different types of fibers, the abundance of water/ground substance in cartilage
multicellular glands are classified based on the
the division (or lack thereof) of their duct, division (or lack thereof) of their secretory portion, and the shape of the secretory portion
what is the effect of using electrons as the energy source on producing the image in the microscope?
the energy goes through the specimen and the microscope has a larger column (than the compound microscope) that inverts the image - the source of energy is at the top now and the bottom is where you see the image (inverted in comparison to the compound microscope)
when the cell is actively assembling polypeptides its chromatin will be -- so...
very diffused to the cell will be much larger - this is what tells us that this cell and a different, smaller cell do not have the same job/level of activity
bone is a very -- tissue that is remodeled --
very dynamic tissue that is remodeled all of the time
size of osteoclasts
very large cells
size of macrophages (with diameter)?
very large cells - 20 to 30 micrometers (yes it's the same as mast cells)
cardiac muscle is very --. it is onyl found in the
very localized - only found in the heart forming the myocardium and at the beginning of the pulmonary vein where it meets the heart
the cells of skeletal muscle tissue are very -- and can stretch from one side of the attachment to the next
very long
all of the fibers in loose CT are arranged
very loosely
there are different types of glycoproteins that will be floating around in the ground substance depending on
the type of CT
CT can be fluid-like (like blood) or hard (like bone) - it depends on...
the types/abundance of cells, type/degree of fluidity/abundance of matrix, and fibers
in cells with gap junctions, the membranes fuse and there are also -- that allow....
there are also pores that allow communication between the cells
what is the relative distribution of fibrocartilage
very restricted
as chondroblasts form the matrix, they become -- in a space called --
trapped in a space called the lacunae
osmium tetroxide allows us to see the membrane and it is called the
trilaminar appearance
non-lamellar bone
type of bone where the collagen fibers inside are not organized. they are randomly ordered - interlacing collagen bundles
where are nucleic acids typically located in the cell? what does that mean for basophilic staining?
typically located in the nucleus, ribosomes, and RER - means that when you are staining tissues with basic dyes/hematoxylin, you stain the nucleus
if the secretory portion does not divide it is called
unbranched technically, but usually we just don't call it anything just leave off the unbranched
we see anchoring junctions a lot between cells that undergo lots of -- so for example..
undergo lots of stress so like in your skin but also between muscle cells
which type of exocrine gland is the most common
unicellular
there are two types of exocrine glands, which are
unicellular glands multicellular glands
2 types of adipose tissue - which are?
unilocular and multilocular adipose tissues
because results of staining can vary based on a number of factors, there is no
universal protocol
what is one way to stain lipids (it's not a specific stain name, just a general process/idea)
use oil since like mixes with like - first freeze the lipids then stain them with oil that will turn them dark/red - indicates the presence of lipids
sectioning frozen specimen must occur using a -- that's within the
using a rotary microtome within the freezer cabinet
what would you use to remove the inorganic material?
using an acidic solution like EDTA or vinegar
EO involves using -- as a template so that the embryo will have a -- skeleton
using hyaline cartilage as a template so that the embryo will have a cartilaginous skeleton
mitochondrial abundance varies between cells and -- cells based on
varies between cells and within a single cell based on activity
in the embryo, there are 2 types of CTs that are very -- and those are...
very similar: mucous CT mesenchymal CT
what differential stain could be used to visualize the elastic fibers more easily?
ver hoeff's - differential stains make it MUCH easier to ID elastic fibers/cartilage
what is the size of osteocytes
very small cells
type 3 collagen fibers are also very -- but very (thickness)
very abundant also but very thin
abundance of cells in loose CT?
very cellular (many cells)- see many many nuclei
filopodia must run in tunnels that are very -- and known as
very small tunnels known as canaliculi
what is the thickness (in a general sense) of the basement membrane (BM)?
very thick
the projections of the osteocyte that form the stellate shape are very -- so they're called --
very thin, so they're called filopodia
collagen fibers are overall very (strength) and (flexibility)??
very tough and inelastic - cannot stretch them
skeletal muscle is VERY --, each individual muscle fiber is --
very vascularized
how do merocrine glands secrete their product?
via exocytosis - the product is carried in secretory vesicles that fuse with the PM where the product is discharged into the lumen of the gland and carried outside of the lumen via the duct
how do osteocytes communicate?
via their filopodia that will make contact with one another
what is ground substance made up of
water, glycosaminoglycans, proteoglycans, and adhesive glycoproteins
because we use -- all TEM micrographs are in --(colors)?
we use heavy metals and that explains why all TEM micrographs are black and white
we see that once the template cartilage has fully disappeared, it means that
we're done growing
osteoclasts are very -- from osteoblasts or osteoprogenitor cells because they are more associated with the --
very different from these other 2 types of cells - more associated with the macrophage family
where can hyaline be found (just 3 examples)
- at the end of the joint - forms rings in trachea - in the tip of your nose
approximate thickness of elastic fibers? like numbers
0.2-2 micrometers
how thick are reticular fibers approx.?
0.5-2 micrometers
1 muscle fiber is -- muscle -- 1 muscle fiber is -- myofiber(s)
1 muscle cell 1 myofiber
how long are type I collagen fibers
1-20 micrometers long
there are 2 ways to section bone to view it as a histological slide (since it's so hard) - these 2 ways are...
1. after you cut the bone, grind it very very thinly so light can pass through 2. remove the inorganic material
what are the functions of fibrocartilage?
1. help with resistance to compression and shear 2. replaces injured cartilage
diameter range of skeletal muscle fibers
10 to 100 micrometers since there's dif kinds of muscle fibers
how thick are intermediate filaments
10-15 nm
osteoclasts can be up to -- micrometers
150
elastic fibers can stretch up to
150% of their length
how many membranes do T tubules have
2 - can see tri-laminar appearance
the periosteum is made of -- layers and there is no clear...
2 layers - no clear limit b/t them
stratified cuboidal epithelium will never have more than
2 or 3 layers
EO involves -- processes that work in --
2 processes that work in parallel
muscle cells can be up to --cm long - what does this mean for their composition?
20cm long, means they have to have many many nuclei b/c otherwise they wouldn't be able to sustain their activity
how thick are microtubules? are they thicker than the PM?
24 nm - thicker than the PM
in the endosteum, we find -- different types of cells
3
what does a desmosome look like
3
the cytoskeleton is a network of
3 different types of filaments
a rotary microtome should be used to cut tissues into sections that are how thick?
3-10 microns thick
in mature bone, the matrix has --% inorganic material, --% organic material, and --% water
65% inorganic 25% organic (collagen) 10% water
how thick is the PM
8-10 nm thick
water in the ground substance can be ~--% of the weight
80%
the axoneme is formed of..
9 double and one central pair of microtubules
although there are 15 types of collagen, --% are of -- types
90% are of 3 types
mitochondria are involved in what central part of metabolism (in general, don't think of steps)
ATP synthesis
in diapedesis, monocytes slow down in the....
BV and crawl in between the endothelial cells to reach the CT
loose CT often surrounds
BVs i think
the CT that further invades the organ to divide the lobes into lobules carries..
BVs often and nerves (known as septa or trabeculae)
when i say 'now we're talking about actual bone in the periosteum' that means we have
BVs that invade/go through/penetrate the calcified matrix
smooth endoplasmic reticulum histology
C - don't pay attention to the rest of the picture
pericytes belong to the
CT
the periosteum is made up of what kind of tissue?
CT
sharpey's fibers are just -- insertions in bone
CT insertions in bone
different types of CT are determined by type of....
GAG/proteoglycan/type of protein/fibers/type of cells
example of a bacterial disease that can be found with a -- stain?
H pylori can be found with an IC (maybe IHC? but i feel like she meant immunocytochemistry) stain
what is an example of a basic dye
Hematoxylin
the cavity that osteoclasts form as they degrade the matrix is called
Howship's lacuna or resorption bay
are the membranes of the golgi able to communicate? is this similar to or in contrast to the RER?
NO - in contrast to the RER (RER membranes communicate)
do microvili beat? does that make sense given their actin core?
NO they do NOT beat - doesn't make all that much sense b/c actin in general is involved a great deal with motion so while microvili might move a little, they certainly do not beat
describe the vascularization of the ECM in cartilage
NOT vascularized
I band
ONLY has actin filaments involved in muscle contraction
what kinds of stains are useful in diagnosing a fungal infection?
PAS and Grocott's methenamine silver stain (GMS) - used to ID fungal organisms
when stained with PAS, the basement membrane is
PAS+
mucous glands stain --
PAS+ (just like the goblet cell)
metachromasia
Property of exhibiting a variety of colors when stained with a simple stain - a term used to describe tissues that are metachromatic, meaning that the stain dyes the tissues a different color than the color of the stain itself. for ex. if you start with a blue dye and it turns green/yellow/purple in the tissues or something
RERs -- (action) and are very (organization)?
RERs communicate and are very ordered - regularly oriented
the lacunae is like a niche in which the cell will
REST
in a TEM the energy source is located -- while it is located at the -- in a compound microscope
TEM = electrons are at the top and look at image at bottom compound = light energy is at the bottom and look at image at top
an important distinction between TEMs and compound microscopes is that
TEM inverts the column
out of the two types of EMs, which one is more comparable to light microscopes?
TEM since it's also 2D
in the sarcomere, actin filaments attach on to the
Z band
all mature cells have common characteristics which include
a cell membrane that limits the cell, a nucleus (sometimes several) and cytoplasm that contains various organelles like mitochondria
what 2 things do the satellite cells start dividing to produce
a cell that will become a myoblast and a separate cell that will just become another satellite cell
junctional complex
a complex of various junctions that occur on top of epithelial cells
the entire muscle itself is limited by...
a dense irregular CT shetah called the epimysium
exocrine glands all have a -- that allows...
a duct that allows secreted product to reach the outside environment
the golgi looks like -- (informal answer)
a flat stack of pancakes
what's an example of a unicellular exocrine gland
a goblet cell
chondrocytes often have a -- droplet
a lipid droplet
instead of being just a serous gland or just a mucous gland, they can be
a mixed gland - some cells produce mucous and some cells produce enzymes in the gland
what is the terminal web?
a network of actin filaments located at the base of the microvilli in certain specialized epithelial cells (such as intestinal epithelial cells) that anchor the terminal web to the apical cell membrane (the actin filaments anchor the web to the apical mem)
in loose CT, the ground substance is very
abundant
loose CT is never super
abundant
the ECM is cartilage is very
abundant
what is the unit membrane
according to my notes, just another term we use for the PM - but from quizlet: a lipoprotein membrane that encloses many cells and cell organelles and is composed of two electron-dense layers enclosing a less dense layer (less dense layer = core of PM) - relates to TEM and the trilaminar appearance
pink coloring in H&E is
acidophilic
what are the 3 shapes the secretory portion can take on
acinar (aka alveolar) tubular tubulo-acinar
what are microvili made up of?
actin (their core) made of microfilaments
the core of stereocilia is made up of
actin NOT microtubules
muscle contraction occurs due to the interaction between -- and --
actin and myosin
there may be many golgi in a cell if the cell is particularly
active
chondrocytes remain -- and mitotic so they --
active and mitotic so they divide
the presence of euchromatin indicates that the cell is... and often associated with..
actively synthesizing proteins and often associated with the presence of a nucleolus or nucleoli
the abundance of RER depends on the
activity of the cells
hematoxylin acts like a -- and it is attracted to the -- parts of cells in tissues
acts like a base, attracted to the acidic parts of cells in tissues - that's why it stains the nucleus
the cells that make up adipose tissue are called
adipocytes
resident cells are able to differentiate into many different things including .... (7) depending on the signal they receive
adipocytes fibroblasts chondroblasts chondrocytes osteoblasts osteocytes pericytes
adipocytes form
adipose tissue, which is a type of CT
tight junctions are the type of junctions in between...
adjacent cells that form BARRIERS
gap junctions allow -- cells to work together as if...
adjacent cells to work together as if they were one cell
lamellar bone is only found in the --
adult
lamellar bone is secondary bone b/c it comes...
after the osteoid/primary bone - it's bone that is mineralized
loose CT is also known as the -- CT b/c it looks very...
aka the areolar CT b/c it looks very aerated (there's lots of ground substance)
in the adult, both types of bone are found in
all bones
all the epithelia in the perotineal cavity are..
all different from each other - each one that lines a dif. cavity is dif. from the other
each type of tissues is made of cells that typically all look -- and even when they do not, they work...
all look alike - even when they don't, they work together to provide a specialized function since that's the definition of tissue
microfilaments are involved in muscle contraction in..
all types of muscle tissue, no matter the type
how does bone aid in locomotion
allows muscle to attach
in reticular tissue, there are almost no -- fibers and -- is very loaded with --
almost no collagen type I fibers and the stroma is very loaded with reticular fibers
mucous CT is also called -- and it is in the --
also called wharton's jelly and it is in the umbilical cord
unilocular adipose tissue is also called -- and is by far the most --
also called white adipose tissue by far the most common (visible in the meat we eat)
ossification can also happen for people with a --, this is the basis for -- printing of
also can happen for ppl with prosthesis - basis for 3D printing of bone
the template cartilage in EO also forms the -- which allows the bones to
also forms the epiphyseal growth plate, which allows the bones to grow in length after birth
because elastic cartilage always has a -- it grows mostly --
always has a perichondrium so it grows mostly appositionally
the mineralized bone matrix always originates from -- and this structure itself is made up of ---
always originates from the organic matrix --> called the osteoid and the osteoid is really made up of collagen bundles
so a desmosome is a type of
anchoring junction
Masson's trichrome
another specific stain that involves 3 colors - purple, pink, and blue or green
microvili are found on the -- part of the cell
apical
what is the more rare type of exocrine gland?
apocrine glands
what are the 2 ways cartilage can grow
appositional growth and interstitial growth
mitochondria within a single cell are not -- so in other words they are not --
are not evenly distributed so not homogenized
the stem peri- means
around
areas of the tissue that appear to be abnormally dark/pigmented may just in fact be
artefact since sometimes these dark areas can just be areas of folded over tissue = called fold artefacts
at each step errors or -- might be created
artefacts
what are the 3 exceptions where these types of cartilage do not have a perichondrium?
articular cartilage (joint) epiphyseal plates (growth plates) fibrocartilage
what kind of cartilage is involved in the joint (it's a sub-type)
articular cartilage which is hyaline cartilage
where are the only areas of the outer surface of the bone where there is no periosteum
articular surfaces and where the tendons and ligaments insert - everywhere else on the outer surface of the bones is covered in periosteum
beacuse there job is to assemble the ribosomes, when we see nucleoli that means the cell is actively...
assembling polypeptides
the stem chondro means
associated with cartilage
why is it important that PAS works really well when trying to visualize details in the membranes of the kidneys?
because most medical diseases in the kidney are evident in the renal membrane so since PAS allows us to observe details on their membranes really well, it tells us a lot about the pathology of the kidneys if there is any
why must we coat the specimen in antibodies in immunocytochemistry?
because on their own, the antigens are too small (even with EM) to see so tagging them with antibodies allows us to see them via fluorescent dyes
why is the skeletal muscle able to regenerate to some extent?
because satellite cells are non-differentiated cells that are stuck to the side of some of the skeletal muscle fibers so when there's an injury to the muscle, satellite cells are activated and they start dividing to produce two things
what is one reason why when cartilage is damaged, it doesn't regenerate well
because the ECM is not vascularized and relies on diffusion for access to nutrients
why is it called unilocular adipose tissue?
because the cells contain only one very large lipid droplet
why is it important that the cartilaginous template for the skeleton is made up of cells with ECMs that are not innervated or vascularized?
because the cells will depend on diffusion for receiving nutrients and oxygen so the cells in the middle of the bone will begin to die and the cells will become hypertrophic where they switch to synthesizing a different type of cartilage
why does euchromatin not appear as dark spots as well
because the chromatin is so diffused it doesn't pick up the stain well
why is it important that the largest component of proteins is the cytoskeleton
because the cytoskeleton contains proteins like microtubules, microfilaments, and intermediate filaments all throughout the cytoplasm
why is it necessary for us to block tissues in either paraffin or resin for light microscopy/TEM?
because the tissue needs to be super thin to use these kinds of microscopes, but the tissue is often too delicate to be able to cut it that thin- so to keep it from tearing while cutting it super thin, we embed it in paraffin or resin - makes it easier to cut it in thin sections without damaging the tissue or leaving behind artefacts
why is H&E so much harder to read than special stains?
because there is so much info on the slide when you stain it with H&E. with a special stain, though, you're generally only asking on question and the particular color you're looking for helps a lot
why are the cardiac muscle cells eosinophilic
because there's an accumulation of mitochondria, cytoplasm, myofibrils, and myofilaments
why are tight junctions occluding?
because there's no space between the membranes of the adjacent cells
why does hematoxylin stain ribosomes
because they are the main area where RNA is concentrated
why are chondroblasts basophilic?
because they have lots of RER that secretes many many proteins that will be found in the matrix - remembering that the matrix is mainly proteoglycans and other proteins, including collagen
why do we see a well-defined nucleolus in fibroblasts?
because they're actively synthesizing the ECM which is made up of a lot of fibers, which are made of proteins
why does the nucleus look very basophilic when fibroblasts are inactive?
because they're not making proteins while inactive so the chromatin is really condensed (it's heterochromatin) and that stains very dark
why do we need to stain tissue in the first place
because very thin tissue does not have any innate color so we can't see anything if we don't stain it
why must we first dehydrate/remove the water from the tissues?
because water doesn't mix with paraffin or resin, which the tissue will eventually be embedded in
why is it called the trilaminar appearance
because you see one thick black line which is the extracellular side of the PM, a gray/lighter space between (NOT WHTE), and then another thick black line, which is the cytoplasmic side of the PM - this is ONE membrane
as chondroblasts become -- by the matrix, they change and become..
become surrounded by the matrix, they change and become chondrocytes
when the bone is placed in an acidic solution it becomes very -- since...
becomes very rubbery since what initially made them hard (the Ca and P) has been removed
eosin behaves like a -- and is attracted to...
behaves like an acid - attracted to the proteins
zonula adherens has a -- appearance
belt-like
zonula occludens has a -- appearance
belt-like
When the ECM is interterritorial it is located...
between the chondrocytes
epiphyseal growth plates are between the -- and the -- at the level of the --
between the epiphysis and diaphysis at the level of the metaphysis
with EO, the cartilage is the intermediate between the -- and the --
between the mesenchyme and the formation of the bone
loose CT is found
between tissues
once the chondroblasts have differentiated from the chondrogenic cells, their relative size is
bigger than the chondrogenic cells
M band
bisects H band
when the silver deposits onto the reticular fibers, they look
black
tight junctions are the basis for the --
blood brain barrier
mast cells are close to the
blood vessels
specialized CTs include things like
blood, bone, or cartilage
chondrocytes form -- when they divide because when mitotic division happens they begin with -- daughter cells that then divide to give -- that form a --
chondrocytes form isogenous groups when they divide because when mitotic division happens they begin with 2 daughter cells that then divide to give 4 that form a group and these are the isogenous groups
how are we able to differentiate elastic cartilage from hyaline cartilage other than looking at the fiber composition of the ECM?
chondrocytes in elastic cartilage are typically larger than they are in hyaline cartilage. there is also much less matrix in elastic cartilage so you'll see many more cells than you would in hyaline cartilage
are chondrogenic cells flattened? what about chondroblasts?
chondrogenic cells are flattened, but chondroblasts are not
what is the specific glycoprotein in the ECM of cartilage?
chondronectin
an example of how mitochondria are not evenly distributed would possibly be that there'd be more mitochondria where..
cilia are anchored
in cross-section, osteons look
circular with a hole in the middle
when the ECM is territorial it is
close to the chondrocytes
sterocilia are more closely related to which of the 2 remaining luminal surface specializations?
closer to microvili even though cilia is in the name because they don't beat
all epithelia have -- cells that participate in...
cohesive polyhedral cells that participate in junctions like tight junctions, gap junctions, or desmosomes
there are many different types of
collagen
there are 2 types of CT fibers which are
collagen and elastic fibers
in dense CT, the most abundant fiber is...
collagen fiber type I arranged in bundles
what type of fibers are in loose CT?
collagen type 1 and 3 and elastic fibers
ECM of fibrocartilage is made up of what kind of fibers
collagen type 1 fibers
what kind of fibers does the ECM contain in hyaline cartilage?
collagen type 2 fibers
what are 4 things you'll find in the perichondrium
collagen type I fibers fibroblasts lots of BVs lots of nerves (the BVs allow nutrients to diffuse)
organic part of the ECM in bone is very rich in -- but it also has
collagen type I fibers but it also has GAGs/proteoglycans/and other proteins special to bones
what kind of fibers are in the elastic ECM?
collagen type II fibers, but also a **** ton of elastic fibers
columnar cells shape? nucleus?
columnar cells are tall and skinny. nucleus is elongated/tall in the long axis of the cell
cells in decalcified bone --
communicate
osteocytes in the compact bone are able to
communicate
gap junctions are -- junctions
communicating junctions
how are osteocytes organized in compact bone vs cancellous bone?
compact = osteocytes follow the collagen lamellae in the osteons cancellous = osteocytes are randomly organized
in cortical bone cross-sections, we see that it is very
compact/dense
RER is composed of very -- with a bunch of ...
composed of very flat membranes with a bunch of ribosomes
if the duct does divide, it is called a
compound gland
whenever you see a TEM in color, know that is is
computerized for helpful distinction, but it's also entirely artificial - there is no pigment in the original TEM
in the center of the osteon, there is the hole known as the haversian canal and there are -- layers that surround the hole. what are these layers?
concentric layers surrounding haversian canal - these are the layers/lamellae of the collagen fibers
heterochromatin
condensed chromatin that cannot be transcribed b/c so tightly wound the machinery cannot reach the promoter to initiate transcription
see epithelial tissue think --
connective tissue below it often
the reticular lamina is synthesized by
connective tissue cells lying beneath
the neurovascular bundles in the haversian canals are
contained
all secretory cells are contained together by a large -- but also by -- all throughout the organ
contained together by a large capsule but also by CT invading the organ
the inside of a multicellular gland contains -- which is made of..
contains parenchyma which is made up of secretory units and ducts
the RER and SER have different functions even though they are a --
continuum
the osteoid is progressively converted to a -- that will form the..
converted to a mineralized osteoid that will form the inorganic part of the matrix
endocrine glands are not organized in the same way as exocrine glands, their cells are organized in
cords/clumps or in follicles
cilia are made up of
core = microtubules
compact bone can also be called
cortical bone or dense bone
covering epithelium is also called -- while glandular epithelium is also referred to as --
covering = just epithelium glandular = glands
there are 2 main types of epithelia which are
covering and glandular
mitochondria have structures called -- that..
cristae that are really just the foldings
the bottom layer of transitional epithelial cells are fairly --(shape)?
cuboidal
what shape are osteoblasts
cuboidal
for some reason (she didn't say), interdigitation occurs a lot with
cuboidal cells
cuboidal cells take on what shape? nucleus?
cuboidal cells are more square and less flat than squamous cells. nucleus is round and large.
the cells on the very bottom of the epithelium are always going to be what?
cuboidal or columnar
cells of skeletal muscle --> shape?
cylindrical
eosin can be used to stain these 3 random things? these are just examples - it's not only these 3
cytoplasm collagen muscle fibers
in general, what is an example of a cell structure that is acidophilic? it will stain what color?
cytoplasm of cells (molecules that like the acidic dyes) - cytoplasm stains pink
what does the cytoplasm contain?
cytosol inclusions organelles fibers that form the cytoskeleton
at the EM level, basal bodies appear as a
dark line at the base of the cilia
you would use the ground bone technique if the tissue were
dead
cells in the transient population are cells typically involved in the
defense system
elastic cartilage can be -- without damage
deformed
in cancellous bone, osteoclasts -- the lamellae
degrade/resorb
after the sections have been exposed to the stain, we then have to -- once more
dehydrate the sections with ascending grades of alcohol and use a clearing agent that removes all traces of the alcohol and raises the refractive index to make the tissue more transparent
fibrocartilage is usually associated with other tissues - in particular with -- tissue
dense irregular CT
if the bundles are disorganized and not regularly oriented, it is -- tissue
dense irregular CT
what kind of tissue is the perichondrium made up of
dense irregular CT
there are two methods of immunocytochemistry, which are?? which one is preferred over the other and why?
direct - expensive indirect - preferred because less expensive
the calcified cartilage is the cartilage that little by little -- and gets -- by bone
disappears and gets replaced by bone
CT is very -- which makes it important
diverse
almost all compound ducts --
divide
in mammals, myoblasts do or do not divide?
do not
length of collagen fibers?
do not have a determined length
how does SER stain at the light level? how does it look?
doesn't stain well, looks white
the top layer of transitional epithelial cells have a -- shape
dome shape - fairly large and roundish
when the zone of reserve is finally depleted, we are..
done growing
mitochondria have a -- membrane
double
appositional growth grows in what direction
downward
why are the cells so strongly attached to one another?
due to a lot of tight anchoring junctions
on a histo section using the ground bone technique, you will see entirely black areas that represent where
dust of the bone deposited as it was ground up such that the light cannot go through the dust so it just shows up as black
bone is constantly being resorbed and reformed = remodeled so the osteons and cementing lines are quite
dynamic - not perfect
interstitial growth has a more active --
early phase
when transitional epithelium is stretched, it can be easily confused with -- but remember that the main difference is that in TRANSITIONAL epithelium...
easily confused with stratified squamous, but remember that the cells will remain LARGE in transitional epithelium as they build up toward the apical part of the cell (if it were strat squamous, the cells would start to shrink and get flat toward the top)
all -- cartilage has a perichondrium
elastic
elastic cartilage is the type of cartilage that is
elastic - can stretch
elastic fibers are in -- cartilage
elastic cartilage
in a transmission electron microscope, it is not light energy that is used, but rather...
electrons
under an SEM, the specimen is bombarded with -- and the image is...
electrons and the image is reflected because the specimen is coated with heavy metals like gold or palladium, which produces a 3D image
shape of chondroblasts
elongated
after the specimen has been dehydrated/cleared, it then gets
embedded in hot liquid paraffin in a mold
as osteoblasts secrete the osteoid, they become...
embedded in the matrix that surrounds them and at this point they differentiate into osteocytes
embryonic CT is mostly found in the
embryo lol
what are the 2 main types of CT?
embryonic CTs mature CT
large glands are encapsulated by -- that sometimes invades the insides of the gland and separates the organs into --
encapsulated by CT that invades sometimes and separates the organs into major lobes
the way that most bones form is -- ossification. it occurs in all of the bones that are NOT flat
endochondral ossification
-- ossification happens for all the other bones and it uses -- as a substrate
endochondral ossification for all the other bones and it uses hyaline cartilage as a substrate
once the cart matrix calcified, we enter the the last zone which is the zone of --, where the lacunae in which the now dead chondrocytes were once in get...
enter the zone of ossification, where the lacunae (empty since the chondrocytes it was holding died of hypertrophy) get invaded by BVs that carry osteogenic cells/osteoclasts
in skeletal muscle, the muscle fiber IS the
entire cell - 1 muscle fiber = 1 skeletal muscle cell
acidic dyes such as -- typically stain any acidophilic element what colors?
eosin or acid fuschin - typically stain acidophilic elements red or pink
Is collagen acidophilic or basophilic?
eosinophilic
in non-lamellar bone, the collagen fibers are --(philicity) when stained with H&E
eosinophilic
philicity of cardiac muscle cells
eosinophilic
philicity of skeletal muscle
eosinophilic
what is the philicty of bone
eosinophilic
when something is stained with eosin it is called
eosinophilic
until the hypertrophic chondrocytes move in to the zone of reserve, there is an
epiphyseal plate
what allows bones to grow long? what type of cartilage are these structures made up of?
epiphyseal plates - made up of hyaline cartilage
the basal lamina is synthesized by
epithelial cells
epithelial cells tend to be -- meaning the distribution of....
epithelial cells tend to be polarized cells, meaning the organelles and membrane composition are not evenly spread out/distributed
see lumen, think --
epithelial tissue
what are the 4 types of tissues
epithelial, connective, muscle, nervous
what are artefacts in histology?
errors introduced in the processing of tissues for microscopy
at the light level, euchromatin appears -- while heterochromatin appears --
euchromatin is more pale, while heterochromatin looks like dark spots
what is the major difference between exocrine and endocrine glands?
exocrine glands keep connection with the surface (usually via a duct)
all of the glands we talk about from here on out are
exocrine, NOT endocrine glands
osteocytes have cytoplasmic -- that osteoblasts do not have
extensions
branching in reticular fibers?
extensive branching
the area between the limit of the tunnel and the filopodia is filled with
extraceullar fluid of the peri space
in terms of a PAS stain, territorial ECM would stain
extremely PAS+ (PAS++)
osteoblasts are extremely -- because the distribution of their organelles such as -- is really uneven and due to the formation of the -- on the apical part of the osteoblast
extremely polarized cells due to an abundance of RER and also the fact that they deposit the osteoid on their apical part
on an EM micrograph, tight junctions look
fairly dark since there's no space in between (PM looks like a dark line under low mag)
how does the nucleus appear in fibroblasts?
fairly large ovoid see a well-defined nucleolus
in the same area where the perichondrium is, -- cells fill up this zone, sending a signal telling the cells to --
hypertrophic cells fill up this zone and this causes them to receive a signal to differentiate (could be telling them to diff. into chondroblasts or osteoblasts, but in this case it's osteoblasts)
an artefact may be produced if an error such as ... in the sectioning step
if the razor is not perfect, you may cut your section perpendicularly or could create foldings
an artefact may be produced if an error such as ... in the dehydration step that affects other steps
if you don't dehydrate well, the embedding will be off and it will not section well
an artefact may be produced if an error such as ... in the fixation step occurs
if you don't fix the tissue well enough, the center of the specimen might rot
an artefact may be produced if an error such as ... in the staining step
if you stain too much or too little you may get poor staining
why is it important that a lot of labs have automation systems now to complete the preparation steps of tissue staining like fixation and dehydration?
important for consistency since we want it to work every time, for technician safety since many of the reagents are toxic, for efficiency/speed since they can take a lot of time, for tracking since it helps keep track of patient samples in a busy lab, and finally because it gives the pathologist a lot more confidence that the procedure was conducted correctly and that the results are viable
where might you find fibrocartilage in a general sense
in areas where you need to resist extension/tension forces
microvili are typically found in cells that --- because they...
in cells that absorb things because they increase surface area
haversian canal
in compact bone, it contains blood vessels and nerves/neurovascular bundles since bone is vascularized and innervated
lamellar bone
in lamellar bone, as the name suggests, the collagen fibers are organized into lamellae (means layers)
where is glycogen predominantly found?
in liver and muscle cells so watch out for that
what is the biggest difference between stratified squamous epithelium and transitional epithelium?
in stratified squamous, the cells flatten little by little (the cells change as they grow) but in transitional, the cells remain large with a fairly round nucleus - they do NOT flatten
where are junctions typically located in the cell?
in the PM
it's an important distinction that covering epithelial tissue is classified based partially on the shape of the cells of the SURFACE layer because
in the basal layer (the layer in contact with the basement membrane) is ALWAYS cuboidal or columnar in all stratified epithelia so it's important we only look at the top layer in stratified when trying to classify
monocytes are only found..
in the bloodstream
how do we freeze the specimens for frozen sectioning
in the cryostat
what is one example of where cilia are found in an epithelium and why
in the epithelial lining of the trachea because debris we breathe in is picked up by the cilia and pushed back toward the outside environment so it is unable to make its way into our lungs
where can elastic cartilage be found
in the external ears, in the epiglottis, and in the inner ear
where can osteoprogenitor cells be found?
in the inner layer of the periosteum above the matrix of the bone, the endosteum (including the haversian/volkmann's canals)
where are chondrogenic cells found
in the perichondrium
stains indicate the -- composition of a cell, but also the...
indicate the chemical composition of a cell, but also the level or type of activity a cell may have
the matrix is not -- by nerves in cartilage
innervated
fibrocartilage is often found where ligaments and tendons..
insert into bone
smooth muscle is -- and controls -- movement
is NOT striated and controls involuntary movement as well
inner layer of the periosteum is -- to the bone matrix and has -- that will become....
is close to the bone matrix and has cells that will become the cells that make the osteoid
interstitial growth is the type of growth that relates to -- groups
isogenous
what is an advantage of frozen sectioning
it allows for rapid diagnosis of fresh tissue
if the bundles are organized and all run in one direction, it is -- tissue
it is dense regular CT
bone is specialized CT because it is -- meaning it's --. despite this, it is still very dynamic
it is mineralized, meaning it's hard. despite this, it is still very dynamic
what does the nucleus look like in fibrocytes?
it is much small and very basophilic
pseudostratified columnar often has what apical specialization
it is often ciliated - makes sense why it's found in the respiratory tract
what is the theca in a goblet cell?
it is the part of the cytoplasm loaded with mucinogen droplets and it is separate from the cytoplasm
although we cannot see lipid droplets at the light level, we can tell they were once present because
it looks foamy where the lipid droplets were
because the matrix is not innervated by nerves in cartilage, you can get stabbed in some places and
it won't hurt
of the components of cartilage, what's different about the perichondrium?
it's not in all types of cartilage
the inner layer of the perichondrium is located -- and it has more than just ---(cell type). it also has --.
it's the layer located directly next to the matrix and it has more than just fibroblasts. it also has chondrogenic cells
can you see gap junctions at the EM level? why or why not?
it's very difficult because the membranes basically fuse to allow the cells to communicate
what is the cytosol
jelly-like material that contains membrane bound organelles and fills up the cytoplasm
2 examples of intermediate filaments
keratin lamin
in order to section specimens, you must first...
kill/fix the tissue/organ (usually with formalin)
there are 2 types of macrophages, which are....
kupffer cells - resident cells transient ones found in the CT
black holes on decalcified bone slides are the...
lacunae
chondroblasts are trapped in
lacunae
osteocytes are contained in
lacunae
osteocytes rest in
lacunae
in cancellous bone, -- are present but they are not organized with that -- forming osteons
lamellae are present, but they are not organized with that circular pattern forming the osteons
the basal lamina itself is made up of what two layers
lamina lucida (lucida means it's clear) lamina densa (densa means you see it)
size of mast cells
large cells (20-30 micrometers in diameter, which is 2-3x bigger than a RBC)
describe the nucleus of chondrocytes
large nucleus with a nucleolus
once the bone marrow cavity forms, the osteoblasts lay down -- on cartilage remnants and -- cells carried by blood become -- that also make it. this is how the bone forms/how the ossification of cartilage occurs
lay down osteoid on cartilage remnants and OPG cells carried by blood become osteoblasts that also make osteoid
philicity of interterritorial ECM? why?
less basophilic b/c there's more collagen and less glycosaminoglycans
how does the cytoplasm stain in osteoprogenitor cells
lightly stains
because gap junctions allow cells to function as a whole, you'll find gap junctions between..
muscle heart cells so that each will contract individually but in sync with each other so that the heart contracts as a whole unit at once
what's an example of a tissue where all the cells don't look alike but work together to provide a specialized function
muscle tissue
the striations are perpendicular to the long axis of the cells to allow the
muscle to contract
when we stain the tissues we must then remove the -- and -- the sections by
must remove the wax and rehydrate the sections using descending alcohols and tap water
each muscle fiber (each muscle cell) contains many --
myofibrils
myofibrils are made up of
myofilaments
is actin or myosin bigger
myosin
volkman's canals contain the
neurovascular bundle
you can never base an identification on a -- only ever on ---
never base it on an absence, ALWAYS base it on presence
you will never see osteoblasts -- up, they will always be in a --
never see them stacked up, they'll always be in a single layer
fibrocartilage is never very -- but it is also never by --
never very abundant, but also never by itself
osteoprogenitor cells are the cells that are elicited if there is a need for..
new bone formation -- they would turn into osteoblasts
Does fibrocartilage have a perichondrium?
no
are inclusions membrane bound
no
are we able to see basal bodies at the light level
no
do type 3 fibers associate in large bundles ?
no
does cartilage ECM contain blood or lymphatic vessels?
no
does the specimen need to be sectioned when using an SEM
no
if the RER were to lose its ribosomes, would it then be the same as the SER?
no
is the ECM of cartilage vascularized?
no
are microfilaments thicker than the cell membrane? how thick are they exactly?
no - 7 nm thick
are we able to see type 2 fibers using LM
no - at least not nearly as well as we could see type I due to the way the light is defracted in microscopy
do we see the lacunae in good sections?
no - if you do, it's likely an artefact
is hyaline restricted to only one mechanism of growth?
no - it can grow appositionally or interstitially (does not apply to the exceptions mentioned in the growth plate/articular joint --> they must grow interstitially since they have no perichondrium)
is elastic cartilage widespread throughout the body?
no - it has a far more restricted distribution than hyaline cartilage
does the ECM of cartilage have sensory receptors or nerves?
no - it is not innervated
can we see the collagen type 2 fibers in the hyaline ECM at the light level?
no - matter of light refraction
do both types of CT fibers look and function the same?
no - they each function and look differently
do adipocytes divide?
no - they're non-mitotic
when fibroblasts are quiescent are they mitotic?
no - they're non-mitotic except for in the case of repair
do stereocilia move?
no - they're non-motile
are we able to use fluorescence/dyes with EM? if yes, which ones? if no, what do we use instead?
no - we can use gold beads to tag them instead
can the separation between the inner and outer layers of the perichondrium be physically observed?
no - you don't see where they separate
because the ECM is not vascularized, there are no -- so all of the nutrients and oxygen the cells need will have to...
no BVs - all nutrients and oxygen will have to diffuse from the neighboring CT
are osteoclasts found in the periosteum as well?
no NEVER
are there cells in ground bone?
no because it's not really living - there are only spaces where the cells or living material was
do we see lipid droplets at the light level? why or why not?
no because they're taken out with the process of making sections
when the zone of reserve is depleted such that no more -- can --, the epiphyseal plate it done and the epiphysis and diaphysis of the bone become..
no more chondrocytes can divide = we are done. the epiphysis and the diaphysis of the bone become confluent and we are done growing --> reached maximal growth (no more proliferation)
at the light level do we see golgi?
no we don't see the golgi themselves, but you do see a lack of staining that indicates their presence - it forms a halo around the nucleus
do we stain our speciments when using TEMs?
no we don't use dyes
is connective tissue localized in the body?
no, it is very large and complicated and all throughout the body
water is in the ground substance in some types of cartilage, but
not all of them
mitochondria are not always -- shaped so don't see one that isn't shaped that way and mistake it for
not always bean shaped - don't mistake a differently shaped one for pathology
the concentric layers are not as easy to see in -- as it is in --
not as easy to see in decalcified bone as it is in ground bone
does cartilage regenerate well?
not at all
where can pseduostratified columnar epithelium be found? is it common?
not common to find it, but it's in the respiratory tract
abundance of cells in dense CT?
not many cells
in LM would you expect to see organelles
not really
is there brush border readily visible at the light level
not really
covering epithelia (CE) is not -- so we do not see any -- among these cells
not vascularized so we don't see any BVs in these cells
multilocular adipose tissue is not very --. we used to think it only occurred in -- but now we see that it....
not very abundant used to think it only occurred in neonates but now we see that it starts to come back as we age
how does mucous stain in H and E
not well - it's very pale
how does the basement membrane stain with H&E?
not well - you can barely see it (most of the time you can't actually even see it, you just know it's there b/c you see the limit b/t the epithelium and the connective tissue - to get it to stain well you need a special stain that turns it blue
osteoclasts have nothing to do with -- cells. they actually do the opposite, which is
nothing to do with bone forming cells - they do the opposite, which is resorb bone
compound acinar gland pic
notice that it looks just like compound tubular except the ends are more bulbous
once the cells receive the signal to differentiate, the CT that made up the perichondrium now carries -- and becomes the -- so now we're talking about actual --
now carries osteoblasts and becomes the periosteum so now we're talking about actual bone in the periosteum
whenever you see a dark spot in a big circle, it is probably the
nucleolus
golgi are often located near a
nucleus
classification of covering epithelium is based on 2 things, which are
number of cell layers shape of the cells of the SURFACE layer
after you cut the bone and grind it very thinly, you obtain ---. it is not exactly --
obtain ground bone - it is not exactly sectioned
once the bones become rubbery, you have obtained -- and it can be..
obtained decalcified bone and it can be processed like all other soft tissues
tight junctions are -- junctions that form -- or --
occluding junctions that form zonula occludens or macula occludens
the same process of ossification can occur in the --, which are the -- and referred to as -- centers
occur in the epiphysis, which are the 2 ends of the bone and referred to as secondary ossification centers
woven bone is often found in the -- where the bone is just starting to --. but can also be found where another bone has been...
often found in the fetus where the bone is just starting to form, but can also be found where another bone has been injured/broken - woven bone will develop first and then become mineralized as the bone heals
acini are often -- cells because their nuclei are
often polarized cells because their nuclei get pushed against the PM so they flatten and then there's a lot of cytoplasm above the nuclei
old bone is -- and new bone is --
old bone is resorbed and new bone is formed
rough endoplasmic reticulum slide
on left of M (but not M obvi)
ex. of where microvili are located in a major organ
on top of the epithelial lining of the intestine
endosteum is always -- thick
one cell
in the bone, there are two populations of cells. one that -- the bone and one that -- the bone
one that makes the bone and one that destroys/resorbs the bone (osteoclasts are the only member of this population)
staining with either a basic dye or an acidic dye isn't sufficient since either one only allows... so they are often...
only allows you to see certain parts of the cell so they are often used in combination - most common combo is H&E
H band
only has myosin
can mitochondria be seen at the light level?
only if they're very very large
the basement membrane is only in contact with what layer
only in contact with the base of the bottom layer (basal lamina) - it is NOT in between all of the layers
in cross-section at the light level, you can only see myofilaments if they are -- because they're
only see them if they're artegact b/c they're really tightly packed
of the lobules that form, only some are -- the rest can be --
only some are fully completed, but the rest can be incomplete
another differential stain, elastic fibers can be stained with is
orcein - that's all i know
the big difference between cancellous and compact is the difference in
organization of their lamellae - compact bone has osteons and cancellous does not
in epithelial tissue, the cells are typically -- and all the same
organized
these growth plates are extremely
organized
in iO, collagen gets organized as -- and as -- in the dense bone that sandwich the trabeculae in flat bone
organized as lamellae and as osteons in the dense bone that sandwich the trabeculae in flat bone
the brown adipose tissue is organized into -- and this is not always true for --
organized into lobules, not always true for white adipose tissue
mesenchymal CT is between
organs in the embryo
cilia microtubules are very regularly ---
oriented/organized
histogenesis means the same thing as
ossification
in the inner layer of the periosteum, osteoprogenitor cells can differentiate into -- that...
osteoblasts that synthesize the osteoid
osteoclasts are the cells that -- in contrast to osteoblasts that --
osteoclasts = resorb bone osteoblasts = form bone
how is the bone marrow cavity formed
osteoclasts that arrive in the bone via BVs penetrating the periosteum resorb the calcified matrix = forms bone marrow cavity
non-lamellar bone has abundant (cell type)?
osteocytes
once osteoblasts are surrounded by matrix, they become
osteocytes
osteoblasts derive from --
osteoprogenitor (OPG) cells
what are the 3 types of cells found in the endosteum?
osteoprogenitor cells osteoblasts osteoclasts
which cell types are contained in the inner layer of the periosteum
osteoprogenitor cells and osteoblasts
cells contained in the inner layer of the periosteum and are the precursors to the cells that form the osteoid are called
osteoprogenitor cells or osteogenic cells (mean the same thing)
the outer surface of the bones is lined with the -- and what lines all of the inner surfaces is the
outer surfaces = periosteum inner surfaces = endosteum
proteins transported to the golgi get..
packaged and modified in the golgi before they're transported to the membrane where they'll be exocytosed
the cytoplasm of fibroblasts is -- and hard to..
pale and hard to see histologically - hard to differentiate the cytoplasm
interterritorial ECM stains much --
paler - more collagen, less glycosaminoglycans
what are shrinkage artefacts and how do they result?
shrinkage artefacts appear as space (appear to be lumens, but they aren't). really they are just where the tissue has separated as a result of shrinking upon dehydration - it appears as a white space, but they were connected before dehydration and that's why it's an artefact
there is one growth plate on each
side of the diaphysis
if there is only one cell layer it is called
simple
what kind of epithelium typically lines ducts of glands?
simple cuboidal
if the duct does not divide, it is called a
simple gland
what are the 4 basic types of simple CE?
simple squamous simple cuboidal simple columnar pseudostratified columnar
the length of tissue processing is dependent on
size and density of the tissue - could be anywhere from several hours to overnight
cartilage is part of the -- system
skeletal
what are the 3 types of muscle tissue
skeletal, cardiac, and smooth
in the beginning of EO, the skeleton is -- meaning that the ECM is not -- or -- and this means..
skeleton is cartilaginous, meaning that the ECM is NOT innervated or vascularized and we know this indicates that the tissue relies on diffusion of the nutrients
how quick is EO
slow
as muscle is developing in the embryo, the precursor cells are --(size) and called --
small and called myoblasts
shape of satellite cells
small and flat
fibrocytes are much (size)
smaller than fibroblasts
special stains give you so much -- in comparison to the -- spent
so much information for the time spent
what kinds of things might pass through the pores in gap junctions?
so small molecules/ions/low resistance signals will pass
skeletal muscle regenerates to..
some extent
-- is really important for homeostasis
space
what are the lacunae in bone?
spaces where the cells rest and then the cells will send extensions of their cytoplasm and communicate
what kind of tissue is bone
specialized CT
what kind of tissue is cartilage
specialized CT
we dehydrate specimens by immersing them in ....then we clear them by
specimen immersed in ascending grades of alcohol to remove water and formalin (start with 70%, go up to 100%). clear them by putting them in an organic solvent such as xylene
shape of chondrogenic cells
spindle shaped
cancellous bone can also be called
spongy bone or trabecular bone
macula adherens has a -- appearance
spot-like
what are the 3 shapes epithelial cells can take on
squamous cuboidal columnar
territorial and interterritorial ECM -- differently
stain
when the cell is stained with eosin, the cytoskeleton filaments stain what color? what does that indicate about their acidity/basicity?
stain pink/orange since they're proteins and that's what eosin does to basic parts of the cell - thus the cytoskeleton is eosinophilic/acidophilic (if it were purple it'd be called basophilic - purple is hematoxylin)
elastic fibers stain with -- stains. in particular, elastic fibers stain a deep -- when stained with --
stain with differential stains. elastic fibers stain a deep purple when stained with verhoeff's hematoxylin in particular
Intramembranous ossification (IO) starts initially from a patch of -- that get the signals to...
starts from a patch of mesenchymal cells that get the signals to become bone (to differentiate into osteoblasts)
what is the shape of osteocytes
stellate (star-shaped, they send out projections all around)
another process working in parallel with the hypertrophic part is around that same bone (that is still made of --) there is a -- made up of
still made up of cartilage. there is a perichondrium surrounding the bone since it's still cartilage
if the limit of the cells can be seen it means that in between the cells, the membranes are
straight
if there are 2 or more layers it is called
stratified
what are the 3 types of stratified epithelium we went over in class?
stratified squamous stratified cuboidal transitional epithelium
what are the kind of cells you'd expect to find in skin
stratified squamous epithelial cells
what kind of epithelium is typical of the esophagus
stratified squamous non-keratinized epithelium
transitional epithelium can be difficult to ID because it's structure can differ depending on if it's
stretched or relaxed
cardiac muscle is -- and controls -- movement
striated and controls involuntary movement
skeletal muscle is -- and controls -- movement
striated and controls voluntary movement
striations in skeletal muscle are oriented how with relation to the cell in longitudinal sections
striation are perpendicular to the long axis of the cell
the accumulation of mitochondria, cytoplasm, myofibrils, and myofilaments is what produces the -- in cardiac muscle
striations
where are type 3 fibers abundant?
stroma and specific organs
cohesive polyhedral cells means that cells are...
strongly attached to each other
because masson's trichrome stains collagen type 1 fibers blue or green, this stain is important in
studying connective tissue
the bone can be formed when there is a suitable -- that is --
suitable substrate that is pre-existing
type 3 fibers are involved in organ --
support
reticular tissue is -- tissue composed mostly of -- and --
supporting tissue composed mostly of reticular fibers and ground substance
most of the time, low magnification tells us .. we only use high mag to
tells us a lot of information already, we only use high mag to verify our hypotheses obtained from low mag
ex. of regular dense CT
tendon
because the ECM does not contain BVs or lymphatic vessels, it tends to be -- and not -- well
tends to be thin and does not regenerate well
collagen fibers have high --
tensile strength
the ECM of cartilage can be described as -- or -- depending on its location
territorial or interterritorial
how do we continue to grow from a fetus to an adult?
thanks to epiphyseal growth plates
special stains can answer questions that cannot .... and can be used for diagnosis of...
that cannot be answered in any other way and special stains can be used for diagnosis of cancer or other medical diseases - mostly the latter, not used super often for cancer
polarization of the epithelial cell reflects...
that functions on the basal part of the cell are not the same as functions on the apical part of the cell
hematoxylin is attracted to the ribosomes, the --, -- and --
the RER the nucleus the nucleolus
myofibrils and myofilaments are not..
the SAME
what are myofilaments
the actin and myosin filaments that are packed together nad organized into myofibrils
what part of the proteins is eosin attracted to
the basic parts of proteins that exist within cells - some amino acid side chains have positive charge
how can we use gold beads to tag the antibodies in EM?
the beads are dense so they will not allow electrons to pass through them so they appear dark on the section
uni adipose tissue is found throughout
the body
multilocular adipose tissue is also know as the -- because it is...
the brown adipose tissue because it is highly vascularized (many BVs running among the adipocytes)
how do apocrine glands secrete product?
the cell product gets released into the lumen of glands when portions of the cytoplasm are pinched off at the apical part of the cell and released into the lumen
sometimes the top layer of transitional epithelia doesn't take on the dome shape, in this case, you can still differentiate it from stratified squamous because
the cells are all fairly large and similar (unlike in stratified squamous where the nuclei are flatter)
how does appositional growth work?
the cells differentiate and become chondroblasts, but as the matrix grows around the cells, they do not move - they stay where they are and that's where the growth comes from
how is one able to differentiate the cells in fibrocartilage and fibroblasts?
the cells in fibrocartilage are chondrocytes and you can recognize that it's fibrocartilage because the chondrocytes are arranged in rows and there's not much matrix around
how is the surface epithelium the origin of GE
the cells in the surface epithelium multiply and grow deeper into the connective tissue
what occurs in the zone of proliferation
the chondrocytes will divide and form a latter type structure b/c they divide mitotically - make more matrix so you see how the bone will grow
CT proper is described according to how densely...
the collagen fibers are packed
gap junctions may be present in an epithelium but it depends on
the function of that epithelium
sarcomere
the functional unit of contraction
a lumen can be described as
the inside of the intestine/vessels/sacs of membrane
in a compound microscope, the -- allows us to see the image of the specimen on the stage down below and your eye is placed on...
the light energy allows us to see the image; place eye on the top
what is the big difference between light microscopes (LM) and SEMs?
the magnification
chondroblasts are cells that form
the matrix of cartilage
the invading CT that divides organs into lobes and lobules can be seen with
the naked eye
under a compound microscope, with squamous cells you can only see...
the nucleus - can't even see the cytoplasm
what is the largest organelle? can it be seen at the light level?
the nucleus - it can be seen at the light level
the -- of nucleoli or if they're -- or not is important in histology
the number of nuclei or if you even see any at all is important
why does the tissue need to be cleared?
the organic solvent removes alcohol to allow infiltration with paraffin wax
with IO, the osteoblasts form the -- that gets organized into tiny -- that aggregate to form the --
the osteoblasts form the osteoid that gets organized into tiny spicules that aggregate to form the trabeculae
what is the organic part of the ECM called
the osteoid or prebone or preosseous tissue - all of these names mean the same thing
what are the 2 layers of the periosteum
the outer fibrous layer inner layer
the perichondrium has 2 layers, which are
the outer fibrous layer and the inner chondrogenic layer
in bone, where is the entry point of nerves and blood vessels
the outer fibrous layer of the periosteum
once osmium tetroxide attaches onto the heads of the phospholipids, we can see
the phospholipid bilayer up close
the cell membrane is sometimes also called
the plasma membrane or plasmalemma
why are goblet cells PAS+?
the product of goblet cells has sugar molecules so wherever mucinogen is, it will turn red
when proteoglycans bunch together they form ... which is the basis for the ...
the proteoglycan aggregate, which is the basis for the gel-like material that forms the ground substance
in decalcified bone, the cells run in...
the same direction as the lamellae = concentric organization
what gives the skeletal muscle striations
the sarcomeres
how does bone provide support
the skeleton
how does bone provide protection
the skull
under low magnification, if you see two thick black lines and you think it's the trilaminar appearance, first look at
the space in between the 2 black lines - if it is irregular aka super white, it means you're actually looking at the membranes of two different cells adjacent to one another - this is TWO membranes, not one/not the trilaminar appearance
what is histology
the study of healthy tissues
RER is involved in
the synthesis of polypeptides
what is a disadvantage of frozen sectioning
the tissue morphology may be compromised, but the process is super quick
in endocrine glands there is a -- connection with the surface and the gland is separated from...
there is a loose connection with the surface, but the gland is separated from the surface and the product is secreted into the blood and carried to target organs
because skeletal muscle cells have many nuclei, they act as -- cells, display a degree of --
they act as syncytial cells, display a degree of syncytium
why are special (really specific) stains clinically valuable?
they answer specific questions in pathology, whereas H&E answers a general question about what types of cells/tissues are present
osteoprogenitor cells are -- cells that are -- but will differentiate into -- if triggered
they are mesenchymal cells that are non-differentiated, but will differentiate into osteoblasts if triggered
the transient population of cells in CT are elicited when
they are needed
what are the holes in the nucleus called?what do they do?
they are pore called nuclear pore complexes that only allow certain things to enter
pseudostratified columnar epithelium is a special epithelium that scientists used to believe was stratified because
they could see nuclei at different heights at the light level
with EM, scientists eventually saw that in pseudostratified, all of the cells...
they could see were touching the basement membrane (despite having their nuclei at different heights), but not all of the cells could reach the lumen (or the top) - not all of them span the entire layer, but all of them do touch the bottom
why are osteocytes not considered quiescent osteoblasts
they keep working and maintain the matrix of bone, they just look different
what is the function of anchoring junctions
they resist mechanical stress
what do the osteoclasts do once they invade the lacunae? what about the osteoblasts?
they resorb the calcified matrix. the osteoblasts will deposit osteoid onto the cartilage
what is the function of chondroblasts
they secrete matrix
what do pericytes do
they surround some blood vessels
what is the function of fibroblasts
they synthesize the extracellular matrix (ECM)
what is the function of cilia
they use their ability to beat to carry out many different functions all over the body
shape of mast cells themselves? (not the nucleus)
they're large and ovoid (but nucleus is spherical)
elastic cartilage never really becomes (thickness)?
thick
because they have to rely on diffusion to receive O2 and nutrients, CE cells are never very -- and if they are, then...
thick and if they are, then the top cells die
because the ECM relies on diffusion, the tissue can never be too
thick b/c the thicker it gets, the slower diffusion occurs and the cells in the middle could die
at low magnification, the PM appears a
thick black line
blood vessels have a very -- wall
thin
elastic fibers are very (thickness)?
thin - just look like lines
to view a specimen under a microscope (BOTH a TEM and a compound microscope), it must be -- enough for the energy to...
thin enough for the light or electrons to go through, thus we must section
what does laminar mean
thin layers
organs are made of
tissues
what is the job of mast cells?
to be involved in allergic reactions (hypersensitivity and anaphylactic reaction); host defense
what is the function of the PM
to keep the integrity of the cell (without it the cytoplasm would spill out and the cell would die), proteins in it allow transduction of signals, and it acts as a barrier for the cell (keeps things in and out)
function of adipocytes
to synthesize and store triglycerides
what's an example of metachromasia?
toluidine blue stains cartilage purple so we say that cartilage is a metachromatic tissue
the internal surface is the surface of the
trabeculae
cancellous bone is sometimes called spongy or trabecular bone because it is formed by a bunch of
trabeculae (little walls of bones)
what are T tubules used for
transmitting information (depolarization of the membrane) when a nerve is sending information --> this is what allows the release of calcium from the sarcoplasmic reticulum
why is it important to note that cuboidal cells tend to have a round nucleus and that that is one of their defining features?
when we can't see the limits of cells, and thus the outline of their shapes, due to interdigitation of the cell membrane, we can still see rows of round nuclei and conclude they're cuboidal cells - can also be done with columnar cells (but looking for a differently shaped nucleus to conclude it's columnar obviously)
the nucleus is the site where -- is contained and it has 2 forms which are..
where DNA is contained - chromatin has 2 forms, which are heterochromatin and euchromatin
simple tubular gland pic
where one of the black arrows is pointing
what is the ruffled border
where the osteclast makes contact with the matrix and it creates foldings that function basically the same as the microvili (inc. SA to help with absorption)
in the space where the osteocytes are contained - the lacunae- there is some leftover space represented as a -- ring. this is known as the -- and it contains the --
white ring- known as periosteocytic space and it contains the extracellular fluid
cartilage will always have -- fibers, they will just be different in different types of cartilage
will always have collagen fibers
fibrocartilage will never be ... it will always be associated with...
will never be by itself - it will always be associated with other tissues
fibrocartilage pretty much always associated with -- tissue and -- cartilage
with dense irregular CT and hyaline cartilage
you will not find -- in all cells and their abundance depends on
won't find SER in all cells - abundance depends on the function of the cell
it doesn't really matter what you call the skeletal muscle cell as long as you include the word -- since it is the...
word fiber since it is what differentiates skeletal from cardiac and smooth muscle cells
non-lamellar bone can also be called
woven bone or primary bone
osteocytes can live for --
years or even decades
elastic cartilage has what color
yellowish
are both types of CT fibers found in the ECM
yes
are osteoprogenitor cells mitotic
yes
can osteoclasts be multi-nucleated?
yes
can other types of cells do diapedesis other than macrophages?
yes
does cardiac muscle have sarcomeres as the functional unit of contraction?
yes
does cardiac muscle have striations
yes
is cartilage metachromatic?
yes
is lamellar bone mineralized?
yes
is the endomysium vascularized
yes
is bone vascularized? innervated?
yes to both
is the unilocular adipose tissue also vascularized?
yes, but not as much as the brown tissue
do macrophages divide?
yes, they are mitotic
how does immunocytochemistry begin?
you cover the specimen with antibodies that will attach to the antigens
at the light level, do we see RER? if yes, why? if no, what can be done about that?
you don't see individual networks of RER, no but there is a special stain that stains it very dark/purple and its an indication of the activity of the cell
how is the indirect method of immunocytochemistry different than direct?
you raise your primary antibody that's attached to the antigen of interest to a secondary antibody called an anti-antibody that can be bought and THAT antibody is the one that gets tagged with a fluorescent dye to visualize them
you will find lamellar bones in -- but the lamellae...
you'll find lamellar bones in both compact and cancellous bone, but the lamellae will not be set the exact same way
toward the top of the epiphysis, you have the zone of --, which is just...
zone of reserve - which is just resting chondrocytes