Module 1 - BIOL 530 copy

what are the three ways to approach the preparation of a specimen?

1) Perfuse Fixation - fixative is perfused through the vascular system and rapidly fixes the tissue 2) organs/samples/tissues can be extracted and submersed in fixative 3) cells can be extracted and isolated from a tissue/organ and then flooded with fixative

what is the connective-tissie matrix composed of?

1) bound water 2) molecules that bind to the water and hold others in place 3) long fibers to give strength and elasticity 4) other sticky molecules like glycoproteins

What are the steps for fixing a tissue?

1) immersion in 10% formalin to kill all living processes 2) series of dehydrations in solutions of increasing % of ethanol 3) saturation with molten paraffin wax until throughly infiltrated 4) placed in a mold and allowed to cool 5) sectioning with microtome 6) immersion in water bath and adherence to slide 7) air drying in 37 degree C oven 8) removal of paraffin 9) rehydration through a series of decreasing concentrations of alcohol until equilibrated with water 10) staining

what do the genes determine in cells?

1) the final shape and size 2) the shape of the nucleus 3) the unique presence and proportion of the cytoplasmic components

What is considered in order to classify connective tissue?

1) the kinds of cells present 2) the types of fibers present-extrecellular component 3) the character of the ground substance-extracellular component

what are the three things you should know about a Transmission Electron Microscope?

1) the source of illumination is electrons 2) the lenses are made of magnets 3) the specimen and the path of electrons are contained within an evacuated chamber

what are the three layers of the trilaminar disc?

1) top layer- neuroectodermal cells that give rise to nerve and epithelial cells 2) middle layer - mesodermal cells that give rise to muscle and connective tissue 3) bottom layer - cells that will form the epithelium for the gastrointestinal tract and glands of the intestinal tract

Which of the following is an example of a cell type belonging to a static cell population? A) a neuron B) smooth muscle cell C) blood cell D) bone marrow cell E) epithelial cell

A

Which of the following structures keeps epithelial cells separated from the connective tissue? A) basement membrane B) gap junction C) hemidesmosome D) terminal web E) desmosome

A

acidiophilic structures in tissues are attracted to which of the following type of dye? A) acidic B) basic C) neutral D) Schiff's reagent E) silver

A

Hyaluronan

A carbohydrate component of proteoglycans in the matrix of many connective tissues. it is a very large molecule that can entrap a large volume of water and contribute to the turgidity of connective tissue

Ehlers-Danlos syndrome

A group of inherited disorders that affect your connective tissues — primarily your skin, joints and blood vessel walls. People who have this syndrome usually have overly flexible joints and stretchy, fragile skin. It is due to an inherited defect in procollagen peptidase and a mutation of the gene encoding the enyme lysyl hydroxylase

Leptin

A hormone produced by adipose (fat) cells that acts as a satiety factor in regulating appetite.

What staining procedure is required to view reticular fibers?

A silver stain or the PAS method must be used to make reticular fibers visible. It is glycosaminoglycans on the surface of reticular fibers that reacts with either of these methods. Hematoxylin and Eosin stain does not render them visible

What is a tendon cell and what relationship does it have to a fibroblast?

A tendon cell is really the same as a fibroblast. It is routinely described as a fibroblast like cell. Its function, that of synthesis and turnover of the fibers and the minimal ground substance of tendons has brought about its name, the tendon cell.

Neutrophils

A type of white blood cell that inactivate and sequester bacteria

Multilocular adipocytes

AKA Brown Fat -Many lipid droplets -Central nucleus -Rich in Mitochondria -Highly vascular -Rich in innervation -Lipochrome pigments

Unilocular adipocytes

AKA White fat cells -Large cells that store lipids -Has a large droplet of lipid that fills the cytoplasm -Causes Nucleus to be pushed to the side and become flattened

Monocytes

An agranular leukocyte that is able to migrate into tissues and transform into a macrophage.

_________________ and ____________ units of measure are only applicable to the electron microscope

Angstrom (A) and nanometer (nm)

non-keratinized stratified squamous epithelium

Appearance: multi-layered, cells become increasingly flat towards surface Functions: resist abrasion and penetration by pathogenic organisms Locations: tongue, oral mucosa, esophagus, anal canal, and vagina

Approximately how many uniquely different cell types are there in the human body? A) 500 B) 200 C) 50 D) 400 E) 100

B

Which of the following is the correct way to name a stratified epithelium? A) named for the shape of the 3rd layer of cells B) named for the shape of the cells at the free surface C) named for the shape of the 4th layer D) named for the shape of the 2nd layer E) named for the shape of the first layer of cells

B

adipocytes arise from which of these germ layers in the embryo? A) endoderm B) mesoderm C) ectoderm

B

which of the following gives connective tissue a pink staining result with hematoxylin and eosin? A) reticular fibers B) collagen fibers C) plasma cells D) ground substance E) fibroblasts

B

which thickness would allow the best detail? A) 10 micrometers B) 2 micrometers C) 4micrometers D) 8 micrometers E) 12 micrometers

B

Before the age of 10 years, in which of the locations or tissues is the highest incidence of tumors expected? A) connective tissue B) epithelial tissue C) bone marrow D) muscle tissue E) nerve tissue

C

The term for transformation of an epithelial tissue from a normal type in a certain location to another normal type but abnormal for that location is: A) dysplasia B) neoplasia C) metaplasia D) polyplasia E) cancer

C

Which of the following correctly defines the location of the apical pole of an epithelial cell? A) lateral surface B) basal surface C) free surface

C

which of the following cell types is not a fixed connective tissue cell? A) mast cell B) fibroblast C) neutrophil D) macrophage E) adipocyte

C

which of the following is true of a unilocular adipocyte? A) stores glycogen B) generates heat C) secretes leptin D) many small lipid vacuoles E) many mitochondria

C

plasma cells

Cells that develop from B cells and produce antibodies.

mast cells

Cells that release chemicals (such as histamine) that promote inflammation.

What is the dominant histological component of dense regular connective tissue?

Collagen fibers that are arranged parallel to one another. Cells are present but not dominant because they are flattened fibroblasts that adhere closely to the collagen fibers.

1 micrometer is equivalent to which of the following? A) 10 A B) 10nm C) 0.1mm D) 0.001 mm E) 10 cm

D

The term for abnormal epithelial cells that have crossed the basement membrane into connective tissue is: A) neoplasia B) metaplasia C) dysplasia D) malignant E) tumor

D

The water based fixative, formalin, performs all of the following except for: A) cross-links proteins B) kills micro-organisms C) dehydrates the tissue D) stops the enzymatic process

D

which of the following is not true about brown fat? A) generates heat B) multiple lipid vacuoles C) many mitchondria D) converts fatty acids into trigycerols E) rich blood supply

D

which of the following mobile cells in loose connective tissue may transform into a family of macrophages? A) neutrophil B) lymphocyte C) eosinophil D) monocyte

D

Using the formula for calculation resolution, calculate the resolution of a microscope when the objective lens numerical aperature is 1.3 and the wavelength og the light source is 400nm. Which of the following solutions rounded to the nearest tenth is correct? A) 2 micrometers B) 2 centimeters C) 2 nanometers D) 2 millimeters E) 0.2 micrometers

E

what type of adipose tissue tends to increase as humans age? A) brown adipose tissue B) white adipose tissue C) unilocular adipose tissue D) multilocular adipose tissue E) both B and C

E

which of the following accurately describes the function of a fibroblast? A) secretes collagen B) secretes elastin C) secretes glycosaminoglycans D) secretes hyaluronic acid E) all of the above are true

E

Microvilli

Fingerlike extensions of plasma membrane of apical epithelial cells, increase surface area, aid in absorbtion, exist on every moist epithelia, but most dense in small intestine and kidney about 6micron long and 0.1 micron wide compose the core of actin filaments

What is the most common fixation chemical?

Formaldehyde (10% formalin in water)

what is ground substance made of?

GAGs, proteoglycans, and multiadhesive glycoproteins

what are the two most common stains used in histology?

H&E and any version of trichrome

Cilia

Hairlike projections that extend from the plasma membrane, play an important role in the respiratory and reproductive trats about 6-10 microns long and 0.2 microns wide they are motile

What staining procedure is required to view elastic fibers?

Hematoxylin & Eosin will make elastic fibers visible. They are densely pink and refractile. However to make them easily visible, a special stain is used, an elastic fiber stain such as Verhoef's.

dense regular connective tissue

How would you classify this connective tissue?

Fibroblasts

In connective tissue, cells that secrete the proteins of the fibers and ground substance. when active they have a bluish stained cytoplasm with hemtoxylin and prominent nucleolus

A- simple columnar epithelial cell B- nucleus C- erythrocyte D- lumen E- blood vessel

Label

A- Mesenchymal cell B- Ground substance C-Fiber

Label A,B and C in the picture of connective tissue

basement membrane

Layer between epithelium and underlying connective tissue

If you cannot make out the boundaries of cells in a simple epithelium, what structure is helpful is determining the identity of that epithelium?

Look at the shape of the nucleus. Nuclei are flat in squamous cells, they are round in cuboidal cells and they are oval shaped in columnar cells.

What are the histological features that enable one to determine whether an observed specimen is of loose connective tissue?

Look to see if the fibers are thin and cells are dominant with a modest amount of ground substance.

What are the dominate features of embryonic connective tissue

Mesenchymal cells and ground substance

What is another term that refers to embryonic connective tissue?

Mesenchyme

Histopathology

Microscopic analysis of diseased tissue

What diagnostic features distinguish between pseudostratified and stratified epithelium?

Not all cells reach the surface, hence the reason for the stratification of the nuclei. True stratified epithelium has only the cells at the basement membrane attached. All other cells in the strata above the basal layer never touch or are attached to the basement membrane.

What is the embedding compound?

Paraffin

what two phases of the cell cycle are displayed in this picture?

Prophase and anaphase

What does the term regular indicate about the histology of a dense connective tissue?

Regular is a term that denotes the spatial arrangement of collagen fibers in adult dense connective tissue. The collagen fibers are parallel to one another.

what does fixation accomplish?

Stops cell metabolism Cross-links or denatures proteins of enzymes Hardens the tissue Kills microorganisms

What are the types of stratified epithelial tissues and where is one site where they are found in the body?

Stratified squamous non-keratinizing: esophagus Stratified squamous keratinizing: epidermis of the skin Stratified cuboidal epithelium: ducts of sweat glands Stratified columnar epithelium: large ducts exiting from the major salivary gland

What does the classification 'dense irregular connective tissue' tell you about the histology?

That the collagen connective tissue fibers are large (wide) and that they run in different directions, that is they are not parallel to one another.

basal surface

The bottom layer of epithelial tissue that attaches to the basement membrane

cell cycle

The regular sequence of growth and division that cells undergo

the basement membrane has been crossed (the dark pink line in the middle) the nucleus to cytoplasm ratio has been upset this would be called a malignant squamous cell carcinoma

This is a comparison of normal epithelium on the left and cancerous on the right. What are some differences you see?

A- adipocyte B- mucous cell (stains lighter because content is water soluble and gets washed away during staining) C- Serous cell (content stains darker bc their content is mostly protein and is not water soluble)

This is glandular epithelial tissue, label A,B, and C

True or False: Resolution is the minimum distance at which two points actually appear as two points (i.e. they are resolvable)

True

True or False: a bacterium can be resolved with a light microscope

True

true or false: tumors arise most commonly in epithelial tissues in adults who are 45 years of age or older

True

monocyte

What is this?

mucous cell, it is lightly stained due to the water soluble contents being washed out during staining and the darkly stained nucleus on the basal side

What type of cell is this and how can you tell?

pseudostratified epithelium, all cells are attached to the basement membrane and seem to have staggered nuclei. This would be found in places like the trachea

What type of epithelial tissue is this and how can you tell? Where would this type of tissue be found?

transitional epithelium the service level cells are dome shaped it would be found in the lining of the bladder and ureter

What type of epithlial tissue is this? how can you tell? and where would it be found?

epithelial tissue (skin) A- eccrine sweat gland B- adipocyte C- sweat gland duct

What type of tissue is this and label

What are the diagnostic features that distinguish transitional from stratified squamous non-keratinizing epithelium?

When relaxed transitional epithelium has surface cells shaped like domes. When stretched the epithelium is reduced to no more than 3 layers of cells. Stratified squamous non-keratinizing epithelium surface cells are always flat, that epithelium always has more than 3 strata of cells

what type of connection is this?

Zonula Occuldens

Lipomas

a benign, slow-growing fatty tumor located between the skin and the muscle layer

stain

a combination of at least two dyes

Trichrome stain

a commonly used stain nuclei ans cytoplasm: red collagen: blue or green Elastic fibers: red or not stained

Proteoglycans

a glycoprotein consisting of a small core protein with many carbohydrate chains attached, found in the extracellular matrix of animal cells.

osmium tetra-oxide

a heavy metal that binds to unsaturated bonds in lipids: stains the lipids black

Mitochondria

a membrane enclosed organelle in eukaryotic cells powerhouse of the cell because it generates most of the cells ATP which is used for energy also involved in signaling, differentiation, cell death (apoptosis) and control of the cell cycle

Rough Endoplasmic Reticulum

a membrane shaped into tubules that form a netowrk. It communicates with the nuclear membrane and the plasma membrane for synthesis and transport of proteins

Golgi apparatus

a membraneous organelle that packs proteins synthesizes in the RER and forms lysosomes

Lysosomes

a membranous bag that contains hydrolytic enzymes used to digest macromolecules

Aniline blue

a negatively charged dye that complexes with a positive charged collagen molecule

Smooth Endoplasmic Reticulum

a network of membranes that lack ribosomes lipid metabolism sequesters calcium in muscle cells detoxification in liver cells glycogen metabolism

what does the ideal candidate for liposuction look like?

a person who is close to their target body weight (within 10-15%), exercises regularly, maintains a healthy diet, and has fairly elastic skin with a few stubborn fat deposits

nucleoid reigon

a region of DNA not bound or confined by a membrane

Cytoskeleton

a system of microfilaments, microtubules, and intermediate filaments. It provides the solid state structures that organelles are transported on maintains the different morphological shape of each cell

epithelial tissue

a tissue that cover the body surfaces , line the gastrointestinal tracts, blood vessels and body cavities

Eosinophils

a type of blood cell that functions to sequester and destroy immune complexes

sudan IV

a typical lipid soluble dye

Neoplasia

abnormally higher proliferation of cells the normal control of mitosis is lost resulting in the formation of benign and malignant tumors

necrosis

accidental cell death in response to injury rapid cell swelling and lysis inflammatory response basically throwing the garbage out the window, it gets everywhere

microfilaments

actin protein 6-8 nm core of microvilli, beneath plasma membrane, element of muscle contraction

Compare and contrast the histological features of an adipocyte, a plasma cell, a lymphocyte and a mast cell

adipocyte- large vacuole of lipid with a peripherally located flat nucleus. plasma cell- round nucleus located eccentrically in the cell with a high density of rough endoplasmic reticulum that renders the cytoplasm very basophilic. The nuclear chromatin of a plasma cell forms a clock face like pattern in the nucleus. lymphocyte -very little cytoplasm showing as a thin rim surrounding a round nucleus that is very heterochromatic. mast cell - round nucleus located centrally and contains many granules

when is argyophilic staining best?

after formalin fixation and is useful on demonstrating very fine fibers called reticular fibers

organs

aggregates of tissue that carry out a specific function

tissue

an aggregate of cells ad extracellular matrix organized to function in a collective manner

what are the three basic body shapes due to differences in adipose tissue?

andriod (apple), gynoid (pear) and ovoid shape

artifact

any alteration in tissue specimens cause by processing

what are some examples basophilic structures?

anything that contains DNA or RNA complex carbohydrates that make up part of the extracellular matrix

what are the three poles/domains in epithelial tissue?

apical, lateral, and basal

which of the following terms means to secrete a small portion of apical cell membrane and cytoplasm?

apocrine

Hemidesmosomes

attach epithelial cells to the basement membrane

Basophilia

attraction of basic (negatively charged) dyes to positively charged tissues

panniculus adiposus

band of fatty tissue located in the subcutaneous layer; thickness varies with age, gender and health.

cells of the human body take on their unique shape and composition just after the ________________________ stage of the human embryological development

blastocyst

what are examples of specialized tissue?

bone and cartilage

_____________________________ has been found to increase when humans are exposed to extreme cold temperature for prolonged periods of time

brown adipose tissue

which fat type needs a more rich blood supply and why?

brown, because it functions to provide heat to the body

what gives a cell their unique identity, receptors, hormones, and influences associated with each cell?

carbs, glycolipids, and glycoproteins which protrude from the plasma membrane

static cell population

cell that no longer divide, once lost they are gone forever ex: neruons, cardiac, or skeletal muscle cells

_____________ are dominant in loose connective tissue. _________________ are dominant in dense connective tissue. _______________________ is dominant in specialized connective tissue.

cells fibers ground substance

fixed cells

cells that are always present in the connective tissue proper

Stable cell populations

cells that divide episodically and slowly ex: smooth muscle and lining cells of blood vessels

Adipocytes

cells that have a large vacuole of lipid (fat cells)

dynamic cell populations

cells that regularly divide ex: blood cells in the bone marrow, skin cells, oral cavity cells

lipoblasts

cells with an abundant clear multi-vacuolated cytoplasm and eccentric darkly staining vacuole-compressed nucleus

collagen fibers

characteristics: bundles!!! about 10 microns in diameters function: provide strength

dense irregular tissue

characteristics: dominant presence of thick collagen fibers arranged in different directions and planes function: resist tension in several directions, wrap some organs

dense regular tissue

characteristics: dominant presence of thick collagen fibers, parallel to one another functions: conduct force, connect bones together, the fibers are extremely strong

elastic fibers

characteristics: thin, straight, branched, single strands about 1 micron in diameter function: elasticity

reticular fibers

characteristics: variation of collagen, very thin, argyophilic (affintiy for silver), rich coat of carbohydrates function: support framework for cells of glands

loose connective tissue

characteristics: widely separated cells, medium to fine fibers, lots of ground substance functions: provide easy access of immune cells to blood vessels and nerves of epithelia, intermediate tissue between skeletal muscle

inclusions

chemically inert substances that appear and disappear during cell activity ex: glycogen, stored lipids, crystals, pigments, keratin

what cell structure does this picture show?

cilia

Heterochromatin

coiled DNA active cell stains dark blue with the H&E stain

what is trichrome stain advantageous in vizualizing?

collagen

what are the three types of connective tissue fibers?

collagen, reticular, and elastic fibers

what are the three cell types that compose the building blocks of epithelial tissue?

columnar, cuboidal, and squamous

connective tissue proper

composed of cells that are either fixed or mobile (wandering) and an extra cellular matrix composed of fibers and ground substance

glandular epithelium

composed of epithelial cells that have differentiated and are equipped with the organelles to synthesize and secrete a given product like mucus, protein, lipid, etc.

brown adipose tissue

consists of many multilocular adipocytes supported and surrounded by reticular and collagen fibers with a high density of capillaries

hollow organs

contain a large singular lumen tissue arranged in layers around the lumen

mucous cells

contains many micelles of mucus making cell stain very light

serous cell

contains many secretion granules that pick up stain

sebaceous glandular cell

contains many small lipid droplets

goblet cell

contains mucus that is stored/released in cycles

muscle tissue

contracts to move bones and regulate blood pressure

what are the two compartments of cells?

cytoplasmic and nuclear compartments

what is the formula for resolution?

d= (wave length of light source/ numerical aperture of the microscope lens)

during starvation, if extreme, unilocular adipocytes ____________________ into early stages and finally loose their all of their _______________

de-differentiate fat

a decrease in body weight will cause a(n) _________________ in leptin secretion. an increase in body weight will cause a(n) ________________ in leptin secretion

decrease, increase

macula adherens

desmosomes physically bind the cells together in smaller areas resembling spots

solid organs

do not have a large singular lumen organs with cortex and medulla ex: kidney. lymph node, lung, spleen, pancreas

Hemotoxylin and Eosin are both _______________

dyes

What are the three types of connective tissue?

embryonic, connective tissue proper, and specialized connective tissue

mitochondrial uncoupling (proton leak)

energy from electron transport system released as heat instead of ATP

keratinized stratified squamous epithelium

epidermis

what type of tissue is this?

epithelial tissue

What are the four types of tissues?

epithelial, connective, muscle, nervous

Two histological structures that can be used to estimate the size of other structures are the _____________ __________________, and their diameters are ________________ and _________________ micrometers, respectively

erythorocyte lymphocyte 7.5 5

what is the difference between prokaryotic and eukaryotic cells?

eukaryotic cells have a "true nucleus" and prokaryotic cells have no nucleus

True or false: Brown fat contains many blood vessels but white fat contains no blood vessels

false

true of false: unilocular adipocytes contain many mitochondria compared to multilocular adipocytes

false

true or false: a dye is a combination of two or more stains

false

True or False: the ticker the section of tissue the more detail can be seen

false! thinner sections are better!

true or false: at birth, the average infant has 15 billion adipocytes

false, they have around 5 billion

android body shape

fat deposits on the middle section of the body, mostly in the abdomen most common in men

Gynoid body shape

fat is deposited on the hips and buttocks most common in women

when fibroblasts are not synthesizing and secreting fibers and ground substance, they are said to be inactive and are usually called _________________

fibrocytes

connective tissue

fills, packs, and connects bone to bone and muscle to bone

squamous cells

flat cells in tissue sections (layered in reality)

nexus

gap junctions connect the cells together via protein lined channels that provide a means for communication by permitting ions to flow from one cells to another

transitional epithelium

has specialized cells that can increase membrane area when stretched and contain extra membrane when relaxed function: stretches readily and permits distension of urinary organ by contained urine Location: lines the ureters, urinary bladder, and part of the urethra

Dense Irregular CT

how would you classify this connective tissue?

what are the two phases of the cell cycle?

interphase and mitosis

Moh procedure

involves excising the cancerous tissue in stages until there is no cancer seen at the edge of the excised tissue sample

A- unilocular adipocyte B- nucleus

label A and B

1) loose 2) dense irregular 3)dense regular

label the types of connective tissue here

what are some side effects from liposuction?

less serious: bruising, swelling, temporary numbness/discomfort in the area treated more serious: blood clots, infection, allergic reaction

which enzyme breaks up the triglyceride molecule into glycerol and fatty acids?

lipase

Nucleolus

located within the nucleoplasm and is not membrane bound, contains RNA for protein manufacturing visible when the cell is not dividing

microtubules

made of tubulin 20-25 nm form the core of cilia play an important role in the transport of molecules throughout the extensive processes of nerve cells

liposarcoma

malignant tumor of fat

Vacuole

membrane bound sacs for storage, digestion, and waste removal contains water solution have no basic shape, size, or structure

adipocytes are created through the differentiation of the __________________

mesenchymal cells

In smokers, over years of heavy smoking the cells of the trachea and bronchi go from pseudostratified columnar epithelium to stratified squamous non keratinized epithelium with dire consequences. This is an example of what?

metaplasia

the perimeter of a unilocular adipocyte is rich is _______________

microfilaments

what are some examples or acidophilic structures?

mitochondria ER certain secretion granules collagen fibers

Lymphocytes

mobile cells of connective tissure proper, emerges from the blood and is a white blood cell

which cell is mobile in loose connective tissue and may transform into a family of macrophages?

monocytes

stratified epithelial tissue

multiple layers of cells

Fat Staining

must use a fat-insoluble solvent and freeze-fracturing

Extracellular substances contain sulphate groups ionized to yield a net _____________ charge

negative

Ribonuclear proteins in DNA and RNA associated with phosphate groups yield a net _______________ charge

negative

Proteins in solution will have ionized carboxyl and amine groups that yield a near ______________pH and a net ______________ charge

neutral pH net positive charge

which of the following cell types is not a fixed connective tissue cell?

neutrophil

Centriole

non-membranous organelle usually composed of nine triplets of microtubules involved in the organization of the mitotic spindle in mitosis and the completion of cytokinesis also a major component of centrosomes are the source of basal bodies

mobile cells

ones that move into and out of connective tissue and their numbers are influenced by inflammation in response to infection

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

Interphase

period of the cell cycle between cell divisions has G1, S, and G2 phases

zonula adherens

physically bind the cells together in a zone near the apical pole

Enzyme histochemistry

product of a specific enzyme reaction that is trapped at its site of formation by a light-dense capturing reagent, usually a heavy metal like lead the fixation process must by mold in order not to kill the enzymes

Apoptosis

programmed cell death external and internal signals like taking out the trash to the curb, to get picked up and taken to a processing station. It is very organized and clean.

Thermogenin

protein that allows movement of protons across mitochondrial membranes rather than having to generate ATP heat is still released

what is the purpose of cholesterol in the plasma membrane?

provides an element of stiffness to the membrane

nervous tissue

provides sensory perception to environment and ability to respond to perceptions

columnar cells

rectangular sections in tissue (multisided columns in reality)

Dehydration

replacing water in a tissue with an organic chemical (like xylene) that is miscible with paraffin (the embedding compound)

what are some examples of artifacts?

shrinkage from fixation and dehydration deposition of foreign pigment during fixation tearing in the tissue from nick in the microtome or inadequate infiltration Uneven staining caused by improper staining Folds in the tissue caused by not placing the section flat Air bubbles trapped underneath the cover slip

Resolution

simply resolving what is present in reality in the specimen

simple epithelial tissue

single layer of cells

Why is Infiltration necessary?

so that the paraffin gradually replaces the xylene

cubodial cells

square shaped cells in tissue (cubes in reality )

metachromasia

staining process where a stain produces more than one expected color due to reactive groups that interact due to proximity

H&E

stands for Hematoxylin and Eosin which is a common stain

what are the three types of cell populations?

static stable dynamic

during starvation where is energy created from?

stored lipid and muscle protein

Identify the epithelium represented by this photograph A) simple squamous B) stratified cuboidal C) stratified columnar D) simple cuboidal E) stratified squamous F) pseudo-stratified ciliated columnar G) Simple columnar H) transitional

stratified squamous

what type and shape of cells are these? what type of connection is there?

stratified squamous epithelium cells desosomes (macular adherens)

organelles

structures that serve to perform functions that require energy 2 types of organelles: membranous and non-membranous

Plasma Membrane

surrounds the cytoplasm and controls traffic into and out of the cell is a lipid bilayer interspersed with cholesterol and proteins

nuclear membrane

surrounds the nucleus composed of two layers numerous pores and openings

Histologically, how do mesenchyme and adult connective tissue differ

the adult tissue contains much, much thicker fibers. the cells are more mature looking and there is a lower concentration of ground substance in adult connective tissue.

Histochemistry

the aspect of histology concerned with the identification of chemical components in biological cells and tissues

parenchyma

the cells in an organ that carry out the functions of that organ

Chylomicrons

the class of lipoproteins that transport lipids from the intestinal cells to the rest of the body

organs like the kidney are surrounded by adipose tissue, why?

the cushion the organs from external blows recieved to that area of the body

What does the term 'transitional' denote about transitional epithelium?

the epithelial cells change in shape due to the stretching or relaxing of the bladder/ureter

Fixation

the first step in tissue preparation. Life is stopped by morphology is preserved

ovoid body shape

the general overall coverage of fat on the body gender non specific

where is most of the fat in humans found?

the hypodermis

Hypodermis

the layer of skin beneath the dermis, which serves as a storage repository for fat

nucleus

the main repository of DNA

resolving power

the minimal distance at which two structures in a specimen can be separated and seen with the microscope as two structures

stroma

the network of loose or dense connective tissue or reticular fibers that provides a framework/support for the parenchyma of an organ

acidophilia

the phenomenon that involves the attraction of an acidic (anionic) dye to a basic (cationic) structure in tissues

cell differentiation

the process by where gene expression results in uniquely different cell types

Immunohistochemistry

the process of detecting antigens in section o intact biological tissue using the principle of antibodies binding specifically to antigens in biological tissues

Dysplasia

the production of abnormal growth patterns due to environmental influence or gene alteration by mutation

plane of section influence

the resulting shape of a section is dependent upon its 3D shape

Anaphase

the shortening of the microtubules, duplicate chromosomes are separated and move towards opposite poles

lateral surface

the side of a cell that faces adjacent cells in epithelial tissue

Argyrophilic

the silver staining process whereby silver nitrate in solution is reduced and the silver is deposited on tissue structure

the cell

the smallest unit of living organism capable of independent existence

apical surface

the surface bordering the lumen in epithelial tissue

liposuction

the surgical removal of fat from the panniculus adiposus beneath the skin with the aid of a strong vacuum

Mesenchyme

the tissue that has the potential to differentiate into all kinds of adult connective tissue

Metaplasia

the transformation of an epithelial cell from a normal tissue type for one area into another normal tissue type but not for that area ex: muscle tissue where nervous tissue should be

___________________ is responsible for non shivering thermogenesis found in brown adipose tissue

thermogenin

why is it important that newborn babies have a high amount of brown adipose tissue?

they lose heat faster than adults due to their surface area to volume ratio

which connection type forces exchange between cells to be carried out by going through the cells in order to control what is absorbed and prevent the entry of bacteria?

tight junctions (zonula occludens)

zonula occludens

tight junctions where adjacent membranes fuse together seal the space between epithelial cells so that no ion or water can flow between them

tissue block

tissue in paraffin wax

pseudostratified columnar epithelium

tissue that consists of a single layer of irregularly shaped and sized cells that give the appearance of multiple layers; found in ducts of certain glands and the upper respiratory tract

why is adipose tissue widely distributed throughout the body?

to help insulate the body.

Why is embedding necessary?

to produce a hardened clock of tissue that can be sectioned

why is the pH of a stain important?

to provide consistency in staining reactions

why do unilocular adipocytes have a close relationship with the capillaries that border them?

to recieve fat deposits from the blood and deposit fatty acids into the blood depending upon the function of the adipocyte at any given time

based on the information presented, which type of epithelium is described? - several layers of cells - all cells are contiguous - surface cells change shape

transitional epithelium

Ribosome

translate mRNA and build polypeptide chains using amino acids delivered by tRNA can be free or bound

adipose tissue stores energy in the form of _______________

triglyceride molecules

true or false: a unilocular adipocyte contains one large vacuole full of lipid

true

true or false: at puberty there is a substantial increase in the size of average adipocytes

true

true or false: in epithelial tissue, the cells are so close together there is very little space for substances in-between

true

true or false: loose connective tissue is continuous within a compartment formed by epithelium and the wrapping of blood vessels and the limiting basal lamina of nerves muscles

true

true or false: stored lipid can be recruited from the fat cell to supply the body with fatty acids as needed for synthesis of cholesterol and other lipid molecules

true

true or false: the smaller the distance (D) between two resolved points, the greater the resolution (R)

true

true or false: the structure being pointed to by the black arrow in this H&E stained specimen is basophilic

true

true or false: the unilocular cell is designed to maximize fat storage and actually has very little cytoplasm

true

true or false: well-differentiated liposarcomas treated with surgery and radiation have a low reoccurrence rate

true

true or false: tendons are about 95% collagen

true!

Meiosis

two divisions of the cell that produce gametes that contain half the number of chromosomes and half the genetic material

Euchromatin

uncoiled DNA the cell is not active

how are tissues adhered to slides?

using protein albumin or a charged slide

PAS positive substances are _________________

water soluble

on the right: no goblet cells, cells are darkly stained, nuclei comprise more area in the cells it is malignant becase the epithelium has migrated through the basement membrane into the connective tissue evidenced in the circle

what are the differences between these two pictures of epithelium?

mast cells, they are stained darker than the surrounding cells and have small granules within them

what is pictured here and how do you know?

this is a polyp from normal colon epithelium also an example of neoplastic growth

what is this?

Adipocytes

what type of cell is this?

mast cells

what type of cell is this?

stratified squamous non-keratinized epithelium

what type of tissue is this?

Prophase

when the chromatin in the nucleus condenses and forms chromosomes followed by the degradation of the nuclear membrane

Metaphase

when the chromosomes align along the metaphase plate in the center of the cell

Cell Homeostasis

when the rate of cell division and cell death are similar

Telophase

when the two groups of chromosomes are separated and the nuclear membrane reforms

lamina propria

where loose connective tissue underlies epithelial cells (like in a gland)

what are the two types of adipose tissue?

white and brown