Histology Quiz 2

Cellular Structures, Epithelial Tissue

Brightfield light microscope

which type of microscope was used to take the image?

scanning em

which type of microscope was used to take the image?

transmission em

which type of microscope was used to take the image?

Fluorescence or confocal light microscope

which type of microscope was used to take the image?

plasma membrane

* Semi-permeable -> fluid mosaic structure
* protection and structure
* controls what comes in and out of the cell
* Communication w/ environment

nucleus

* Contains DNA/genetic material
* Site of DNA replication, transcription
* Can affect appearence of nucleus
* controls/regulates cell function

ribosomes

function in protein synthesis

rough er

* Ribosomes attached
* Protein modification/packaging
* Folding, adding sugar groups

smooth er

* Lipid synthesis
* Calcium storage-> muscle cells
* Detoxification -> liver cells

golgi apparatus

Cellular product processing, sorting, shipping

secretory vesicles

Package product in golgi and travel to release product outside of cell

mitochondria

* Makes energy (ATP) through aerobic respiration
* Prevalent in active cells like muscle or kidney

the cytoskeleton

* Network of protein filaments found throughout cell
* Provides internal structure, assist w/ specialized functions like intracellular transport, cell movement, cell division

microtubules

* “Steel beams”
* Made of protein tubulin
* Involved in intracellular transport
* Important in large cells like neurons

intermediate filaments

* “Logs”
* Form shape and structure throughout cytoplasm
* Help w/ cell-cell attachment at junctions
* Important for epithelia especially skin

microfilaments

* Smallest filaments made of actin
* Important for cell movement

cellular inclusions

Some cells have storage function and have abundant deposits within cytoplasm that aren’t membrane bound

functions

Different cell types are specialized for different ______

ribosomes and rough ER

cells have very basophilic cytoplasm, and also have very euchromatic nuclei, what structures might be enriched in the cytoplasm of these cells?

produces lots of proteins, very transcriptionally active

Cells have very basophilic cytoplasm, and also have very euchromatic nuclei what might these features suggest about the function of these cells?

mitochondria, lysosomes, golgi apparatus,

The parietal cells in this image have very acidophilic cytoplasm what structures might be enriched in the \n cytoplasm of these cells?

mitochondria would need to produce lots of energy, lysosomes, golgi would have secretory functions

The parietal cells in this image have very acidophilic cytoplasm What does that tell you about the \n function of these cells?

lipids or high sugar areas

The cells in this image have multiple white \n structures in their cytoplasm what could they be?

not intensely, must use EM to see more detail

How does the plasma membrane stain with H&E?

plasma membrane w/ TEM

What structure is pointed at in the photo and what microscope was used?

purple, basophilic

The nucleus stains ___ in H&E because it is _______

nucleus w/ H&E

What structure is pointed at in the photo and what microscope/technique was used?

nucleus w/ TEM

What structure is pointed at in the photo and what microscope/technique was used?

basophilic, purple

When ribosomes are concentrated in one part of the cell, the cytoplasm there will be ____ as a result and appear _____ in H&E staining.

function requires lots of proteins

What might you infer about the activities of a cell with an abundant supply of ribosomes in its cytoplasm?

ribosomes w/ TEM

What structure is pointed at in the photo and what microscope/technique was used?

doesn’t stain intensely bc of lipid abundance

how does smooth ER stain w/ H&E

same as ribosomes, basophilic and purple

how does rough ER stain w/ H&E

Cells with major secretory functions, pale pink stained region near nucleus

In what type of cells will the golgi apparatus be apparent in H&E? How does it appear in them?

secretory product inside

What does the appearance of secretory vesicles depend upon?

secretory vesicle

What is this?

golgi apparatus

The arrows point to what pale staining cell structure?

acidophilic, bright pink

How do mitochondria stain in H&E

pink, they need lots on energy and are active (like muscle/kidney)

What color is the cytoplasm of cells with abundant mitochondria? What could be inferred about these cells?

mitochondria

What cell structure is this?

Mitochondria

What cell structure is this?

microtubules

green in image

microfilaments

Red in image

cellular inclusions

What cell structure is the photo and example of?

tissues

The cells of the body aggregate and organize \n into cooperative groups called ______

Organs

_______ are then assembled from multiple types of cells and tissues, working cooperatively

epithelial, connective, muscle, nervous

What are the 4 types of tissues in the human body?

lining internal and external surfaces

Where is epithelial tissue found?

primary barrier

Epithelia form _______ between us and the world

covering and protecting surfaces, mediating what enters the body, secretion, sensation

what are 4 main functions of epithelial tissue?

cell junctions, basement membrane

Epithelia adhere tightly through _____ and attachment to a ________ to create a strong protective surface

polarized

epithelia are ______ because they have 2 different sides

apical side

faces external environment/lumen not attatched to tissue

basal side

attached to basement membrane+underlying tissue

basement membranes

what do the pink lines in the figure represent

Attachment to underlying connective tissue, support and organizes epithelium, regulate what materials cross epithelium

What are the basement membrane’s key functions?

Hemidesmosomes

special junctions that attach epithelial cells to basement membrane

laminin and collagen

basement membranes are a dense, self-assembling, mesh-like network of ____ and _____

sticky glycoproteins and reticular collagens

What attaches basement membranes to underlying tissue?

tight, adherens, desmosomes, gap

order where the junction types are found from apical to basal

cell-cell junctions

\n Help epithelial cells adhere to their neighbors and communicate with one another to form a tough, continuous, selectively permeable surface

tight junctions

Prevent molecules and pathogens from passing in between cells, creates an apical membrane domain

adherens junctions

Reinforces strong cell-cell connections by connecting actin networks of adjacent cells

desmosomes

Connects intermediate filament cytoskeletons of adjacent cells for strong cell-cell adhesion

gap junctions

Creates pores that connect cells for cell-cell communication

tight and adherens

What junction type(s) form a continuous belt around cell

tight

What junction type(s) prevent pathogens and toxins from crossing epithelium via extracellular space

gap junctions

What junction type(s) connect the cytoplasm of adjacent cells to promote cell-cell communication

adherens and desmosomes

What junction type(s) connect cytoskeletons of adjacent epithelial cells

desmosomes

What junction type(s) form extremely strong “spot-weld” connections to allow epithelial cells to adhere to one another

claudins and occludins

What are tight junctions made of?

cadherins and catenins

What are adherens junctions made of?

cadherins

What are desmosomes made of?

connexins, circular patches between cells

What are gap junctions made of and what structure do they form?

apical

Which surface can microvilli and cilia be found on

Microvilli

* Increase apical surface area to increase absorption capabilities
* Actin based internal structure
* Not mobile

cilia

* Larger than microvilli
* Microtubule based
* May be mobile 
* Often move same direction to create current
* To move fluids over cell surface or function in intercellular signing
* More likely to be visible w/ light microscopy

cilia

What is shown in the image?

microvilli

What is shown in the image?

\# of cell layers and cell shape

What 2 criteria determine epithelia classification?

Psedostratified epithelia

* Single layer of cells w/ varying shape
* Nuclei at different heights but all still tough basement membrane
* Relatively uncommon-> found primarily in respiratory system

simple columnar

* Often notably internally polarized
* Cytoplasm can hold multiple structures for protein production secretion ect
* Can carry out absorption w/ microvilli
* Present where absorption or secretion occur
* Ie digestive system

simple cuboidal

* Thin enough for efficient absorption but enough cytoplasm to hold organelles for functions like energy production
* Common in places like the kidney where active transport is required (can generate the ATP required)

simple squamous

* Can often only see nucleus w/ minimal cytoplasm
* Great at rapid exchange of materials, can diffuse easily across
* Often found in places where rapid diffusion important
* Line blood vessels, alveoli of lung

simple squamous

What type of epithelia?

simple cuboidal

What type of epithelia?

simple columnar

What type of epithelia?

Psedostratified

What type of epithelia?

simple cuboidal, kidney

What type of epithelia? Where could it be located?

simple squamous, alveoli, blood vessel lining

What type of epithelia? Where could it be located?

Psedostratified, respiratory system

What type of epithelia?

simple columnar, digestive system

What type of epithelia?

Non-keratinized stratified squaemous, mouth

What type of epithelia? Where could it be located?

transitional, urinary system

What type of epithelia? Where could it be located?

keratinized stratified squamous, skin

What type of epithelia? Where could it be located?

endocrine

Is the gland endocrine or exocrine?

exocrine

Is the gland endocrine or exocrine?

Serous

Is the gland producing a serous or mucous product?

mucous

Is the gland producing a serous or mucous product

stratified epithelia

* At least 2 distinct layers
* Only 1 basal most layer contacts basement membrane