Histology Exam 1
Where can you find epithelial secretion?
Gastric glands
What are the light microscopic features of glycogen?
0.01-0.04 micrometers; Observed as a purple haze region of the cytoplasm (metachromasia) with toluidine blue-stained specimen.
What are the light microscopic feature of the endosome?
0.02-0.5 micrometers; Not visible by light microscopy
What are the light microscopic features of the ribosomes?
0.025 micrometers; Not visible in light microscopy
Kinesin is the?
+ end directed motor
Dynein is the?
- end directed motor
1 picometer=
.01 Angstroms
What are the light microscopic features of the cytoskeletal elements?
0.006-0.025 micrometers; Only observed when organized into a large structure (muscle fibrils)
What are the Light microscopic feature of the plasma membrane?
0.008-0.01 micrometers; Cannot be seen by light microscopy
What are the light microscopic features of secretory vesicles?
0.05-1.0 micrometers; Observes only when vesicles are very large.
1 Angstrom=
0.1 nanometers
What are the light microscopic features of the peroxisomes?
0.2-0.5 micrometers; Visible only after a special enzyme histochemical staining
What are the light microscopic features of lysosomes?
0.2-0.5 micrometers; Visible only after special enzyme histochemical staining.
What are the light microscopic features of the mitochondria?
0.2-2 x 2-7 micrometers; Sometimes observed in favorable situations as very small, dark dots; visible in living cells stained with vital dyes (Janus Green)
What are the light microscopic feature of lipid droplets?
0.2-5, up to 80 micrometers; Readily visible when very large; appear as large empty holes in section.
What are the Light microscopic features of the nucleolus?
1-2 micrometers; Roughly circular, basophilic region within the nucleus; visible in living cells throughout interphase with interference microscopy.
What are the types of Exocytosis?
Constitutive Pathway (Continuous, delivery to cell surface) and Regulated Secretory Pathway (Regulated delivery to the cell surface)
1000 nanometers =
1.0 micrometers
1000 micrometers =
1.0 millimeters
10 Angstroms =
1.0 nanometers
What are thick filaments?
15 nanometer myosin II filaments, 1.5 micrometers in length, 200-300 molecules per thick filament, parallel but staggered array.
What is the diameter of a microtubule?
20-25 nanometers
What is collagen?
3 alpha chains, rich in glycine and hydroxyproline, forms fibrils 15-200 nanometers in diameter and 68 nanometer banding pattern.
What are the Light microscopic features of the nucleus?
3-10 micrometers; The largest organelle within the cell with distinct boundary; often visible nucleoli and chromatin pattern region.
What is the classification of the ECM of elastic cartilage?
Contains elastic fibers and elastic lamellae in addition to type II collagen.
What are thin filaments?
6-8 nanometer F-actin filaments that are 1 micron long.
What is the diameter of actin?
6-8 nanometers
What are the dimensions of a Red Blood Cell?
7.8 micrometers in diameter and 2.6 micrometers thick
What is the diameter of the intermediate filaments?
8-10 nanometers
What is epithelium compose of?
A cell membrane, a nucleus, and basement membrane.
What does the epimysium surround?
A collection of fascicles
What subcellular changes would you expect to see in the hepatocytes of animals fed a high fat diet over the course of a week?
A dramatic increase in the number of peroxisomes in hepatocytes.
What does the perimysium surround?
A fascicle
What is used to cover the tissue section in Autoradiography?
A liquid photographic emulsion. After it is covered, the exposure is developed like film.
What are centrioles?
A pair of cylinders built from 9 microtubule triplets
Describe what the Golgi looks like on TEM?
A series of stacked, flattened, membrane-limited sacs or cisternae and tubular extensions embedded in a network of microtubules near the microtubule-organizing center
What is the fascia adherens?
A transverse component; serves as anchoring site for thin filaments.
What is the banding pattern of the sarcomere?
A,I,H,M
What is the function of Simple columnar epithelium?
Absorption, secretion and protection
What is the function of Simple cuboidal epithelium?
Absorption, secretion, conduit, barrier
What is necrosis?
Accidental cell death due to injury. Rapid cell swelling and lysis, Inflammatory response
What neurotranmitter causes motor intervation?
Acetylcholine
What are the cytoskeletal elements?
Actin, Intermediate, and Microtubules
External lamina are boundaries of?
Adipocytes and connective tissue
What is muscle tissue made up of?
Aggregates of specialized, elongated cells arranged in parallel array, whose primary role is contraction
Where do you find smooth muscle?
Alimentary canal, blood vessels, genitourinary and respiratory tracts
Where can you find Acidic and basic cytokeratins?
All Epithelial cells
What are dense bodies of smooth muscle?
Alpha actin, associated with the plasma membrane bound actin. They secrete Connective tissue matrix and Gap junctions that propagate contraction.
Neutral Buffered Formalin reacts with?
Amino groups of proteins
What is immunocytochemistry?
An Antigen/antibody reaction where the antibody is conjugated with an enzyme, heavy metal or fluorescent dye?
What is required for muscle regeneration?
An intact external lamina
Basic dyes react with?
Anionic groups such as phosphates, sulfates, and carboxyl groups.
What are the elements of epithelial polarity?
Apical domain, lateral domain, and basal domain
Type I collagen represents the major collagen type in?
Aponeuroses, Bone, and Dermis of the skin
What are the light microscopic features of the Rough ER?
Area of 5-10 micrometers; Often observed as a basophilic region of cytoplasm, referred to as the ergastoplasm.
What are the light microscopic features of the Golgi apparatus?
Area of 5-10 micrometers; Sometimes observed as negative-staining region; appears as network in heavy-metal-stained preparations; visible in living cells with interference microscopy.
In a typical cell, the cis side of the Golgi is found?
At or very near the location of gamma tubulin of cells in interphase
Where can you find skeletal muscle?
Attached to bone
What is the sequence of the Contraction cycle?
Attachment, Release, Bending, Force Generation, and Reattachment.
What are the structural features that define epithelial tissue?
Avascular, with no extracellular matrix. It is enervated and has a variety of cell junctions. It has functional and morphological polarity: apical, lateral, and basal domains. There is a free surface lumen, a basement membrane rich in protein polysaccharides and the cells are always ready to divide
What are the steps of phagocytosis?
Bacterium is grabbed by Fc Receptor, and brought into the cell by the terminal web. The bacterium is then enveloped into a phagosome and the phagosome is fused with the lysosome to be eaten
What is the function of stratified columnar epithelium?
Barrier and conduit
What is the function of stratified cuboidal epithelium?
Barrier and conduit
What is the function of transitional(urothelium) epithelium?
Barrier and distention
What is the function of stratified squamous?
Barrier and protection
What are the components of the serous membrane?
Basal lamina, connective tissue, and epithelium. There is no muscularis mucosae.
What are the features of the basal domain?
Basement membrane, cell-to-extracellular matrix junctions, and plasma membrane infoldings.
Type IV collagen is characteristic of?
Basement membranes
The trans-Golgi network transports vesicles to four locations in the cell which are?
Basolateral plasma membrane, Apical plasma membrane, Endosomes, and Apical cytoplasm
Where can you find loose connective tissue?
Beneath epithelia of the mucosa and serosa associated with epithelia of glands, its surronds the smallest blood vessels
How are contractions regulated?
By availability and removal of calcium
What is the procedure for sectioning?
Blocks are trimmed, sectioned with a microtome, and mounted to a glass slide
Which tissues have renewing cell populations?
Blood cells and epithelial cells
What color does hematoxylin dye?
Blue
Describe Adult bone
Bone is composed of osteons, concentric lamellae, and is vascular and nerve elements travel from the periosteal and endosteal surfaces via volkmann's canal
What connective tissue covers bone?
Bone is covered in a connective tissues periosteum and has a simple endosteum lining the internal cavities
Describe Immature bone
Bone tissue does not have lamellae, has relatively more cells per unit, appears woven because of collagen, and cells are more randomly arranged.
What are the components of the skeletal system?
Bone tissue, Other connective tissue (hematopoietic tissue, fat tissue, hyaline cartilage, dense regular), Blood vessels, and nerves.
Type I collagen represents the major collagen type in?
Bone, Tendon, and Dermis
Ectoderm gives rise to?
Brain and nervous system; Neural Crest; Epidermis and associated structures
In a simple branched tubular gland such as those found in the pyloric region of the stomach, the secretory portion is?
Branched
Periodic Acid-Schiff Reaction is used to stain?
Carbohydrates, glycogen, and basement membranes.
What is the function of the purkinje fibers?
Cardiac conducting cells that generate and rapidly transmit the contractile impulse to the myocardium in a precise sequence.
Which cell populations are incapable of exiting from G0 phase?
Cardiomyocytes
In patients with muscular dystrophy, a unique histological feature observed in mature skeletal muscle cells in a centrally-located nucleus. What other muscle cells have this feature?
Cardiomyocytes and Smooth Muscle Cells
What are the steps of Vesicular Endocytosis?
Cargo protein lands in cargo receptor, The coated pit is formed, The coated vesicle is formed, The vesicle is coated, The vesicle then uncoats, then vesicle is ready to fuse.
Acidic dyes react with?
Cationic groups such as amino groups of proteins.
What does depolarization of the T-tubule cause?
Causes calcium release and sarcomere contraction.
Pinocytosis is?
Cell drinking, non-specific vesicle size, constitutive, and clathrin-independent
What makes up connective tissue?
Cells and extracellular matrix
Where can you find Vimentins?
Cells of mesenchymal origin such as endothelial cells, myofibroblasts, some smooth muscle cells. Also can be found in some cells of neuroectodermal origin.
Describe Dense regular connective tissue.
Cells sparse, little ground substance, densely packed collagen fibers arranged in a parallel array for maximum strength.
Which tissues have static cell populations?
Central Nervous, cardiac, or skeletal
Lipid rafts are rich in?
Cholesterol
What cells make up cartilage?
Chondroblasts (isogenous) and chondrocytes (found in lacunae)
What are the 4 components of the nucleus?
Chromatin, Nucleolus, Nuclear envelope, and Nucleoplasm
Describe a longitudinal (sagittal) cut?
Cutting a surface in half creating 2 hemispheres left and right
What is epithelioid tissue?
Closely apposed cells that lack a free surface or lumen. Typical of most endocrine glands. It possesses a basement membrane and is mostly from mesoderm.
What is the organization of tendon tissue?
Collagen fibrils and tendinocytes--->Fascicles (endotendineum)--->Groups of fascicles (peritendineum)--->Tendon (epitendineum)
What are the 3 connective tissue fibers?
Collagen, Reticular, and Elastic
What is the classification of the ECM of fibrocartilage?
Combination of dense connective tissue and cartilage (Type I and II); It calcifies during bone repair; no perichondrium
What are the 2 types of bone?
Compact (dense) and Spongy (cancellous)
What happens during prophase?
Condensation of chromosomes; breakdown of nuclear envelope; disappearance of the nucleolus; appearance of kinetochores.
What is adipose tissue?
Connective tissue in which adipocytes are the primary cell type and there is a rich blood supply.
Where do you find connective tissue?
Connective tissue underlies or surrounds other tissues.
Tissues
Consist of cells and extracellular matrix
What does the sarcolemma consist of?
Consists of plasma membrane, external lamina, and reticular lamina
A transverse cut is another name for?
Cross Section
Which parts of the cell dye with eosin?
Cytosol, organelles, cytoskeleton, and cell membranes
What are the features of apoptosis?
DNA fragmentation; Decrease in cell volume; loss of mitochondrial function; membrane blebbing; formation of apoptotic bodies
What are the electron microscopic features of the nucleolus?
Dense, nonmembranous structure containing fibrillar and granular material.
What are the basic protein subunits of microtubules?
Dimers of alpha and beta tubulin; gamma tubulin found in MTOC is necessary for nucleation of microtubules.
What are the artifacts of fixation?
Distortion at the edges; Variation in consistency of fix; Swelling or shrinking of cells
What is the shape of actin?
Double-stranded linear helical array
Where can you find compound tubular glands?
Duodenum: Submucosal glands of Brunner
Explain the Sliding filament model.
During contraction, the length of the A-Band remains the same, while the I band and H band shorten.
Describe skeletal muscle.
Each fiber is a multinucleated syncytium formed by the fusion of myoblasts. It has a polygonal shape with a diameter from 10-100 microns. The nuclei are found in the periphery, just beneath the plasma membrane.
What is the embryonic origin of nervous tissue?
Ectoderm
What is the embryonic origin of the skeletal system?
Ectoderm and Mesoderm
What are the 3 embryonic germ layers?
Ectoderm, Mesoderm, and Endoderm
What is the embryonic origin of epithelial tissue?
Ectoderm, Mesoderm, and Endoderm
What are elastic fibers?
Elastin and Fibrillin, Fibrillin forms 10-12 nanometer microfibrils
Which microscope can see the plasma membrane?
Electron microscope
Endoderm gives rise to?
Embryonic Gut: Inner lining of digestive tract, Inner lining of respiratory tract, and glands (including hepatic and pancreatic)
Epithelioid tissue originates from mesoderm and is commonly found in?
Endocrine glands
The epithelium lining the lymphatic vessels are composed of?
Endothelium
Where can you find epithelial transport?
Endothelium
Where can you typically find simple squamous epithelium?
Endothelium, mesothelium, alveolae, and Bowman's capsule
What is the function of white adipose tissue?
Energy storage, insulation, cushioning of vital organs, and secretion of hormones.
Where can you typically find stratified squamous epithelium?
Epidermis, rectum, oral cavity, esophagus and vagina
Where can you find stereocilia?
Epididymis, ductus deferens, hair cells
4 Basic Tissue Types
Epithelial, Connective, Muscle, and Nervous
Which tissue type consists of all three germ layers?
Epithelium
Where can you find epithelium?
Epithelium covers body surfaces, lines cavities, and makes up glands
How can you characterize epithelium?
Epithelium is characterized by close cell apposition and location at a free surface
Visceral smooth Muscle is found in the tongue. True or False?
False, Visceral Striated muscle is found in the tongue.
Chromosomes are duplicated at the beginning of mitosis.
False; Chromosomes are duplicated during S phase of mitosis.
Collagen fibrils have a 28 nm banding pattern. True or False?
False; Collagen fibrils have a 68 nm banding pattern.
Contraction in striated muscle is controlled by the availability and removal of sodium.
False; Contraction in striated muscle is controlled by the availability and removal of calcium.
Exocrine glands secrete products (hormones) into connective tissue where they enter the bloodstream.
False; Endocrine glands secrete products (hormones) into connective tissue where they enter the bloodstream.
Endothelium is the simple cuboidal epithelium derived from the mesoderm that lines blood vessels. True or False?
False; Endothelium is the simple squamous epithelium derived from the mesoderm that lines blood vessels.
Eosin is a basophilic dye that carries a net positive charge and reacts with anionic groups such as phosphates and sulfates.
False; Eosin is an acidic dye that carries a net negative charge and reacts with cationic groups such as amino groups.
Kinesin is a plus-end directed motor that carries its cargo along microtubule tracks from the cell periphery towards the MTOC.
False; Kinesin is a plus-end directed motor that carries its cargo along microtubule tracks from the MTOC to the cell periphery.
The smooth endoplasmic reticulum of active secretory cells is basophilic and is often referred to as the ergastoplasm.
False; The rough endoplasmic reticulum of active secretory cells is basophilic and is often referred to as the ergastoplasm.
Because elastic cartilage lacks a perichondrium, no appositional growth can be evidenced.
False; because fibrocartilage lacks a perichondrium, no appositional growth can be evidenced.
Reticular fibers are composed of type III collagen and are eosinophilic.
False; reticular fibers are composed of type III collage and are PAS-positive.
What are the intercalated disks composed of?
Fascia adherens, maculae adherentes, and gap junctions
What is the hierarchical arrangement of muscle from largest to smallest?
Fascicles->muscle fiber->myofibrils->myofilaments->sarcomere->sarcoplasm->sarcoplasmic reticulum->sarcolemma
What is a communicating junction?
Gap junctions that allow direct communication between adjacent cells by diffusion of small molecules.
Membrane transport by simple diffusion involves?
Fat soluble or small uncharged molecules
Where can you find hyaline cartilage?
Fetal skeletal tissue; epiphyseal plates; articular surface of synovial joints; costal cartilages; nasal cavity; larynx; trachea; bronchi
What are intermediate fibers?
Fibers between red and white (pink)
Describe Dense irregular connective tissue.
Fibroblast are sparse; There is little ground substance, and is mostly collagen fibers in bundles oriented in various directions
What are the fixed cell populations in connective tissue?
Fibroblast, Macrophages, Adipose cells, Mast cells, Undifferentiated Mesenchymal cells.
What do you find in connective tissue?
Fibroblast, Nuclei, Elastic fibers, Collagenous fibers, and Ground substance.
When the cardiac cells die, what replaces the dead cells?
Fibrous connective tissue (scarring)
What are the 4 steps of Tissue preparation?
Fixation, Embedding, Sectioning, and Staining
What are the electron microscopic features of the Rough ER?
Flattened sheets, sacs, and tubes of membranes with attached ribosomes.
What is the electron microscopic feature of the Smooth ER?
Flattened sheets, sacs, tubes of membranes without ribosomes attached
What is the function of elastic cartilage?
Flexible support
What is the function of cartilage?
Flexible support; resistance to compression and deformation; template for bone growth; cushioning
What is the active ingredient of Neutral buffered Formalin?
Formaldehyde
Type VII collagen
Found in anchoring fibrils of skin, eye, uterus, and esophagus; secretes basal lamina to connective tissue fibers.
Type IV collagen
Found in basal laminae; provides support and filtration barrier.
Type II collagen
Found in hyaline and elastic cartilage; homotrimeric; fibrilar; provides resistance to intermittent pressure.
Type I Collagen
Found in loose and dense connective tissue; Accounts for 90% of body collagen; heterotrimeric; fibrillar; provides resistance to force, tension, and stretch
Type III collagen
Found in loose connective tissue and organs; forms reticular fibers; fibrilar; provides a supportive scaffold for specialized cells.
The Apical domain is directed toward the?
Free surface or lumen
The ectoderm, mesoderm, and endoderm appear during what phase of development?
Gastrulation
What fixative is used for Electron Microscopy
Gluteraldehyde and Osmium Tetroxide
What types of stains will stain nerve tissue?
Golgi Silver stain, Cajal's Gold stain, and Weigert's Potassium Dichromate
What is found within mast cells?
Granules that contain vasoactive and immunoreactive substances that mediate hypersensitivity reactions, allergy, and anaphylaxis
What is the function of elastic fibers?
Help limit distensibility of tissue and prevent tearing from excessive stretching.
Describe Loose connective tissue.
Highly cellular; Sparse collagen fibers; Abundant ground substance
What are the methods used in histology to observe cells?
Histochemistry/Cytochemistry/Immunochemistry; Hybridization techniques; Autoradiography; Organ tissue culture; Cell and organelle separation; Specialized microscopic techniques and microscopes.
Which plane of section would clearly reveal the spindle shape of a smooth muscle cell?
Tangential section
What is the classification of Hyaline Cartilage?
Homogenous and amorphous; type II collagen; large amounts of GAG; Undergoes calcification
The larynx contains what type of collagen?
Hyaline and Elastic
What are examples of GAGs?
Hyaluronic Acid, Heparan sulfate, Chondroitin 4,6-sulfate, Heparin, Dermatan sulfate, and Keratan sulfate
What does calcium phosphate form?
Hydroxyapatite crystals
What are the cartilage specific collagens?
II, VI, IX, X, and XI
What is a example of a useful diagnostic technique in histology?
Immunohistochemistry
Where are microtubules found?
In cilia and flagella
Where does the hemidesmosome anchoring occur?
In epithelia subject to abrasion and shearing forces (Cornea, skin, oral cavity, esophagus, and vagina)
Where are actin filaments found?
In microvilli; contractile element of muscle; beneath plasma membrane; leading edge of a moving cell.
Where can you find monocilia?
In rete testis and vestibular hair cells for sensory
Where can you find focal adhesions?
In the basal domain of epithelial tissue
What does the endomysium surround?
Individual fibers
What are the 4 shapes of bone?
Long, Short, Flat, and Irregular
What are the electron microscopic features of the cytoskeletal elements?
Long, linear staining pattern with width and features characteristic of each filament type.
Where can you find fibrocartilage?
Intervertebral disks, symphysis pubis; articular disks; menisci; triangular fibrocartilage complex; insertion of tendons
Where can you find epithelial absorption?
Intestines, proximal convoluted tubule
Bone formation without preexisting cartilage model is called?
Intramembranous bone formation
Interstitial growth is displayed in the?
Isogenous groups
What is the function of the Basement membrane?
It attaches epithelium to connective tissue.
What is the function of the plasma membrane?
It is used in ion and nutrient transport; recognition of environmental signals; cell-to-cell and cell-to-extracellular matrix adhesions
Why is immunohistochemistry used?
It localized a specific protein in cells of a tissue section, it can be used as a diagnostic for typing tumors, and can be used to detect infectious agents.
What is ground substance?
It occupies space between cells and fibers; Consists mostly of water, proteoglycans, multiadhesive glycoproteins, and GAGs.
What is the function of the zona adherens?
It provides a band of lateral adhesion between epithelial cells by connecting to the actin cytoskeleton.
What is the function of the macula adherens?
It provides a spot junction between epithelial cells by connecting to intermediate filaments; particularly strong attachment.
What is the purpose of Autoradiography?
It provides information about the location of radioactive materials within tissues.
What is the disadvantage of using gluteraldehyde?
It requires expertise and expensive equipment.
What are the disadvantages of Neutral Buffered Formalin?
It will lose neutral lipids, small molecules, and carbohydrates
What is the function of the Basal Lamina?
Its the structural attachment site of epithelium and connective tissue seen at the EM level of observation.
What are the 4 classes of intermediate filaments?
Keratins, Vimentin/Vimentin-like, Neurofilaments, and Lamins
Where can you find epithelial excretions?
Kidneys
In bone, the small space encapsulating an individual cell is called a/an?
Lacuna
What do the purkinje fibers look like?
Large diameter with a pale-er cytoplasm fibers.
What are white fibers?
Large fibers with less myoglobin and fewer mitochondria; high peak muscle tension; They fatigue rapidly. They are fast-twitch fibers.
Where can you find Simple tubular glands?
Large intestine: intestinal glands of the colon
Where can you typically find stratified columnar epithelium?
Largest ducts of exocrine glands and anorectal junction
What are gap junctions?
Lateral component; allows cells to behave as a syncytium.
Plicae are?
Lateral specialization of intestinal epithelial cells
Describe a coronal cut
Tangential to a surface, like cutting the highest part of the skull off.
Where is mesothelium
Lines the body cavities
Where is endothelium?
Lines the vascular system
What is the function of the sER?
Lipid and steroid metabolism; detoxification
The ____ portion of the cell membrane functions as a barrier while the ______ portion determines functions like transport, signal transduction or adhesion.
Lipid, protein
Undifferentiated mesenchymal cells of the adventitia of venules give rise to early?
Lipoblast
What is paracrine secretion?
Local effect, diffusion through connective tissue
What is the function of an Occluding junction?
Localized sealing of plasma membrane of adjoining cells; It separates luminal space from intercellular space and connective tissue; It establishes functional domains in the plasma membrane
Where is the late endosome?
Located deeper in cytoplasm near golgi and nucleus, and typically becomes lysosome (pH 4.7)
Where is the Early endosome?
Located in cytoplasm near plasma membrane.
What cells belong to the transient cell population in connective tissue?
Lymphocytes, Plasma cells, Neutrophils, Eosinophils, Basophils, and Monocytes
Reticular fibers are part of the extracellular matrix of?
Lymphoid tissues
What cells belong to the MPS?
Macrophage, Kupffer cell, Alveolar macrophage, Pleural and peritoneal macrophage, osteoclast, microglia, Langerhan's cell, Fibroblast-derived macrophage, and Dendritic cell
What is an example of apocrine glands?
Mammary glands
What are the electron microscopic features of secretory vesicles?
Many relatively small, membrane-bounded vesicles of uniform diameter; often polarized on one side of the cell.
What is the function of connective tissue?
Mechanical reinforcement, Immune surveillance, Transport and diffusion of nutrients and waste, and Energy storage.
What is the function of intermediate filaments?
Mechanical strength
What are the electron microscopic features of the lysosome?
Membrane-bounded vesicles, often electron dense.
What are the electron microscopic features of the peroxisome?
Membrane-bounded vesicles, often with electron dense crystalloid inclusions
What are the three types of exocrine glands?
Merocrine, Apocrine, and Holocrine
What is the embryonic origin of muscle tissue?
Mesoderm
The epithelium of the serosa is composed of?
Mesothelium
What does the serous membrane consist of?
Mesothelium, basal lamina, and connective tissue
What composes the brush border of kidney tubule cells?
Microvilli which are mad of actin.
What modifications can you find in the apical domain?
Microvilli, stereocilia, and cilia
Where can you find epithelial receptors?
Taste buds of tongue and retina of the eye
What happens during metaphase?
Mitotic spindle organizes to align chromosomes on the metaphase plate.
What is the basic protein unit of actin?
Monomer of G-Actin
Where are lamins found
Most differentiated cells and all nucleated cells
What fills up the sarcoplasm?
Mostly myofilaments
What histological feature is indicative of an immature state?
Mucous connective tissue, Epiphyseal plate, Woven bone, and Prevalence of reticular fibers. Cancellous bone is indicative of maturity
What is Warton's Jelly?
Mucous connective tissue; gelatin-like material of the umbilical cord with fine fibers
Skeletal muscle fibers are best described as?
Multinucleate cellular units
Stratified Columnar
Multiple layers of column-like cells
What is the structure of transitional epithelium?
Multiple layers, top layer is cuboidal when collapsed and squamous when distended
Purkinje fibers are modified...?
Muscle cells
Describe Cardiac muscle.
Muscle fibers consist of numerous cylindrical cells arranged from end-to-end; The nuclei are centrally located; Cells are 10-15 microns in diameter, and from 80-100 microns long.
What does muscle consist of?
Muscle tissue, connective tissue, and nerves.
Cajal's Gold stain is used to identify?
Neuroglial cells
Where are neurofilaments found?
Neurons
Which connective tissue cell type has properties of smooth muscle cells?
Myofibroblast
What is responsible for contraction?
Myofilament interaction.
What does actin interact with?
Myosin
What is the charge of Eosin?
Negative, it is an acidic dye
What is the purpose of Nerve Tissue?
Nerve tissue receives, transmits, and integrates information from outside and inside the body to control the activities of the body.
Nerve tissue consists of?
Neurons and various supporting cells such as Neuroglial, Schwann, and Satellite cells.
What fixative is use for Light Microscopy?
Neutral Buffered Formalin
Which type of cartilage is highly vascular?
No cartilage is vascular
Do serous cells stain with PAS?
No they do not, Goblet cells, Glycogen, Reticular fibers, and cartilage are PAS-positive
What is the shape of a microtubule?
Nonbranching long hollow cylinder
What are the electron microscopic features of lipid droplets?
Nonmembranous inclusions; generally appear as a void in the section
What are the electron microscopic features of glycogen?
Nonmembranous, very dense grapelike inclusions.
What is the polarity of an intermediate filament?
Nonpolar due to staggered tetramer; spontaneous assembly
What is the light microscopic feature of the Smooth ER?
Not visible in Light microscopy, cytoplasm in region of sER might exhibit distinct eosinophilia
Mesoderm gives rise to?
Notochord; Mesenchyme (Bone and cartillage, Circulatory system, and Dermis); Somites (Muscles, Excretory system, Gonads, and outer covering of internal organs.)
Which of the following structures stain blue with H&E: Cytoplasm, Collagen fibers, Nucleus, Elastic fibers, or Decalcified bone matrix?
Nucleus
Which parts of the cell dye blue?
Nucleus, nucleolus, and Ribosomes
What are the junctional complexes of the Lateral domain
Occluding junctions, Anchoring junctions, and communicating junctions
How is connective tissue characterized?
On the basis of its extracellular matrix.
What are lacunae?
Open spaces with osteocytes.
What is the active ingredient in Gluteraldehyde?
Osmium
What cells make up bone?
Osteoprogenitor cells, osteoblasts, osteocytes, and osteoclasts.
Where can you find compound acinar glands?
Pancreas: excretory portion
What is an example of a merocrine gland?
Pancreatic acinar cells
What are the mediums used in Embedding?
Paraffin, OCT, and Resin
Appositional growth is displayed in the?
Perichondrium
What is the function of the Mononuclear Phagocytic system?
Phagocytosis, secretion, antigen processing, antigen presentation.
What are the types of specialized microscopy?
Phase Contrast, Dark-field, Fluorescence, Confocal scanning, UV, Polarizing, Electro, and Atomic Force
What are the types of Endocytosis?
Pinocytosis, Receptor-mediated endocytosis, and Phagocytosis
What is the most aggressive tumor type derived from white adipose tissue?
Pleomorphic liposarcoma
What is the charge of Hematoxylin?
Positive, it is a basic dye
What is Apoptosis?
Programmed cell death; External and internal signals
Functions of epithelium
Protection, Containment of body fluids, and Absorption and secretion.
What is the function of the rER?
Protein synthetic system; chemical modification of proteins; membrane lipid synthesis.
What are the integral membrane proteins?
Pumps, Channels, Receptor proteins, Linker proteins, Enzymes, and Structural proteins
What fiber is not found in connective tissue?
Purkinje Fibers
What color does H&E dye?
Purple
What happens during telophase?
Reconstitution of nuclear envelope around chromosomes at each pole; nucleoli reappear; cytokinesis.
What color does eosin dye?
Red
What are examples of dense regular connective tissue?
Tendons, ligaments, and aponeuroses
What is the procedure for staining?
Remove paraffin with organic solvent, rehydrate for hematoxylin, dehydrate in alcohol for eosin, apply permount and cover slip.
Where can you typically find transitional epithelium?
Renal calyces, ureters, bladder, urethra
What is the function of fibrocartilage?
Resists deformation under stress
Fibers that form a supporting network in myeloid and lymphoid tissues are called?
Reticular fibers
Which of the following would not be characterized as an inclusion: Glycogen, pigment, neutral fat, secretory granules, or ribosomes?
Ribosomes
What are the nonmembranous organelles?
Ribosomes, Actin filaments, Intermediate filaments, microtubules, and centrioles
What is the shape of Intermediate filaments?
Rope-like
Which tissues have stable cell populations?
Smooth muscle and endothelial cells of blood vessels
The distance between two Z-lines is equivalent to the length of the?
Sarcomere
What is an example of holocrine glands
Sebaceous glands
What is the function of pseudostratified epithelium?
Secretion, absorption, conduit, surface transport
Stratified Cuboidal
Several layers of cube-like cells
Stratified Squamous
Several layers of squamous cells
What are the characteristics of multicellular glands?
Simple/compound (Branching of duct); Tubular/alveolar (acinar); Mucous/serous (type of secretion)
Simple Columnar
Single layer of column-like cells
Simple Cuboidal
Single layer of cube-like cells
Simple Squamous
Single layer of squamous cells
What happens during anaphase?
Sister chromatids separate and are pulled to opposite poles
What are the striated muscles?
Skeletal and parts of cardiac
A T-tubule system can be found in?
Skeletal muscle and Cardiac muscle
What are the types of muscle tissue?
Skeletal, Cardiac, and Smooth.
Where can you find epithelial protection?
Skin and bladder
Where can you find simple coiled tubular glands?
Skin: eccrine sweat gland
Where can you typically find simple cuboidal epithelium?
Small ducts of exocrine glands, surface of ovary, kidney, tubules, thyroid follicles.
What are red fibers?
Small fibers with large amounts of myoglobin and mitochondria; they have great resistance to fatigue but generate less tension. They are slow-twitch fibers
Where can you typically find simple columnar epithelium?
Small intestines, colon, stomach lining, gastric glands, gallbladder
What are the characteristics of smooth muscle?
Specialized for slow, prolonged contraction; Spontaneous contractile activity; No discrete neuromuscular junction
Describe smooth muscle.
Spindle-shaped cell with centrally located nucleus; No striations, and no T-system; 0.2-2 microns in diameter and 20-200 microns in length; Smooth muscle contains dense bodies.
What are the electron microscopic features of the Golgi Apparatus?
Stacks of flattened membrane sheets, often adjacent to one side of the nucleus.
Where can you find branched acinar glands?
Stomach: mucus secreting glands of cardia
Where can you find simple branched tubular glands?
Stomach: mucus secreting glands of the pylorus
The composition of the basal laminae is collagen, proteoglycans, laminin, and entactin. what are their functions respectively?
Structural attachment, Compartmentatization, Filtration, Regulation and signaling, and Tissue scaffolding
What is the function of the skeletal system?
Structural support, protection, movement, mineral reservoir
Where can you find white adipose tissue?
Subcutaneous connective tissue, Greater omentum, mesentery, retroperitoneal space, around the kidneys, palms, soles, beneath visceral pericardium, in the orbits surrounding the eyeballs
Where can you find compound tubuloacinar glands?
Submandibular salavary glands
Where can you find dense irregular connective tissue?
Submucosa of hollow organs and the reticular layer of the dermis
What is the function of bone?
Support; protection; reservoir for calcium and phosphate.
What does the mucous membrane consist of?
Surface epithelium, Basal lamina, lamina propria, and muscularis mucosae
What are the Electron microscopic features of the nucleus?
Surrounded by two membranes containing nuclear pore complexes and perinuclear cisternal space; regions with condensed and diffuse chromatin pattern
Where can you typically find stratified cuboidal epithelium?
Sweat gland ducts, large ducts of exocrine glands, anorectal junction.
Weigert's Potassium Dichromate stain is used to identify?
The Lipid of myelin sheath
The terminal cisterna of the sarcoplasmic reticulum are closely associated with what system?
The T-system of the plasma membrane at the A-I junction.
Where can you find elastic cartilage?
The pinna of external ear; external acoustic meatus; eustachian tubes, and larynx
Cytochalasins are drugs that interfere with actin polymerization into microfilaments. If you add cytochalasin to cultured mammalian cells that have just begun mitosis, whist is most likely to happen?
The cells will complete mitosis and arrest at cytokinesis
What is a triad?
The combination of the T-tubule and the two terminal cisternae.
What are the Electron microscopic features of the plasma membrane?
The external membrane and membranes surrounding membranous organelles of the cell; two inner and outer electron-dense layers separated by an intermediate electron-lucent layer
What is the freeze fracture technique and what is it used for?
The freeze fracture technique is used to observe the sides of the membrane. The frozen membranes split along hydrophobic plane to expose an E-Face and a P-Face
What happens to the cardiac function at the site of the injury?
The function is lost
Where do you find cardiac muscle?
The heart, superior and inferior vena cava, pulmonary veins
What is the mode of action of Gluteraldehyde?
The heavy metal binds to phospholipids
What is bending of the contraction cycle?
The hydrolysis of ATP; 5 nanometer linear displacement of the myosin head.
Stereocilia are sparsely distributed, and are found in?
The male reproductive tract in the ductus deferens and epididymis
What is the nucleus?
The membrane-limited compartment that contains the genetic information.
The muscular system consists of contractile cells and is responsible for?
The movement of body and its parts
What is important about sectioning?
The plane of section is very important
How is radioactivity used in Autoradiography?
The radioactive particles emitted, strike the silver halide crystals and create a latent image, the silver halide is then reduced to silver.
What is the z-disc?
The region at the end of each sarcomere, which binds the actin filaments.
What is force generation of the contraction cycle?
The release of inorganic phosphate; power stroke; ADP lost from myosin head.
Where is calcium stored in muscles?
The sarcoplasmic reticulum
Silver stain is used to see what part of nerve tissue?
The synaptic boutons on purkinje cells
What zone of bone stains with PAS?
The zone of hypertrophy
What zone of bone stains most strongly with BrdU, a marker of cellular proliferation?
The zone of proliferation
What is the function of focal adhesions?
They anchor actin filaments into basement membrane; They are mechanosensitive
What is the function of hemidesmosomes?
They anchor the intermediate filaments into the basement membrane.
What is the purpose of muscle satellite cell?
They are responsible for the skeletal muscle's ability to regenerate with limited capacity
What is the function of fibroblasts?
They are the principle cell of connective tissue, they synthesize collagen, elastic and reticular fibers and complex carbohydrates of ground substance. They are activated in growth or wound repair.
What is the function of communicating junctions?
They create conduits between two adjacent cells for passage of small molecules.
What is the function of the centrioles?
To align the mitotic spindle during cell division
What is the function of the lateral domain?
To communicate with adjacent cells
What is the purpose of embedding?
To convert tissue into a solid form that can be sliced.
What is the purpose of sectioning?
To make thin slices of tissue viewable by microscopy.
What is the purpose of Vesicular Transport?
To move large molecules into, out of, and within a cell; maintains integrity of the plasma membrane.
What is the function of Exocrine glands?
To secrete products directly onto a surface or through ducts or tubes connected to a surface.
What is the function of the early endosome?
To sort and recycle proteins of endocytotic pathways (pH 6.2-6.5)
What is the purpose of fixation?
To stabilize and preserve the tissue.
What is the purpose of staining?
To visualize the tissue slices (add color)
Where can you find visceral striated muscle?
Tongue, pharynx, diaphragm, and esophagus
Where can you find cilia?
Trachea, bronchi, oviducts for transport
Where can you typically find pseudostratified epithelium?
Trachea, bronchial tree, ductus deferens, efferent ductules of the epididymis.
What is the function of simple squamous epithelium?
Transepithelial transport or exchange; barrier
The epithelium of the bladder is composed of?
Transitional epithelium
What is the maculae adherentes?
Transverse and lateral component; bind muscle cells to one another and prevent pulling apart under strain of regular contractions.
What stain will color collagen and reticular fibers?
Trichrome
Brown fat or multiocular adipose tissue is associated with heat production.
True
Collagen fibers are the most abundant structural component of the connective tissue. True or False?
True
Collagen forms fibrils of 15-200 nm in diameter. True or False?
True
Collagen proteins are rich in glycine and hydroxyproline. True or False?
True
Each collagen molecule is composed of a triple helix of alpha chains. True or False?
True
Electron microscopy offers more resolution (and the ability to visualize subcellular organelles) as compared to light microscopy because the wavelength of an electron is significantly smaller than that of light,
True
Loose connective tissue is characterized by sparse collagen fibers and abundant ground substance in order to facilitate diffusion to surrounding epithelia.
True
Osteoclast activity is positively regulated by parathyroid hormone and negatively regulated by calcitonin. True or False?
True
Osteoclasts from the leading edge of a bone remodeling unit.
True
The fetal skeleton is composed of hyaline cartilage.
True
What are the electron microscopic features of the endosome?
Tubulovesicular structures with subdivided lumen containing electro-lucent material or other smaller vesicles.
What are the electron microscopic features of the Mitochondria?
Two-membrane system: outer membrane and inner membrane arranged in numerous folds; in steroid-producing cells inner membrane arranged in tubular cristae
What is the ECM of bone composed of?
Type I and some type V collagen; GAGs, glycoproteins, sialoproteins; mineralization of the matrix.
What is the territorial matrix of hyaline cartilage composed of?
Type II/IX collagen
What are reticular fibers?
Type III collagen, 20 nanometers in diameter, its PAS-positive, more sugar groups than collagen, form network of fibers.
What is the pericellular matrix of hyaline cartilage composed of?
Type VI/IX collagen and sulfated proteoglycans
What are the types of exocrine glands?
Unicellular and Multicellular glands
Where can you find simple acinar glands?
Urethra: paraurethral and periurethral glands
What is the basic protein subunit of the intermediate filament?
Various intermediate filament proteins.
Where can you find elastic fibers?
Vertebral ligaments, larynx, and elastic arteries
What are proteoglycans?
Very large molecules with a protein core and many long chained polysaccharides covalently bound to the core protein.
What are the electron microscopic features of the ribosomes?
Very small dark dots, often associated with rough ER
What is Mesenchyme?
Viscous ground substance and fine (reticular) fibers, consistent with the limited stress on the growing fetus.
What is the procedure for Embedding?
Wash, dehydrate in alcohol, clear in organic solvent, and infiltrate with melted paraffin.
In ordinary connective tissue, the predominant component of ground substance is?
Water
What is release of the contraction cycle?
When ATP binds to myosin head and induces conformational changes.
What is reattachment of the contraction cycle?
When myosin head binds tightly to a new actin molecule
Which of the following fibers has the largest diameter: Red fibers, intermediate fibers, white fibers, purkinje fibers, or fibrillin?
White Fibers
What type of adipose tissue tends to increase as humans age?
White adipose, and Unilocular adipose tissue
What are some artifacts of sectioning?
Wrinkles, small pieces falling out, scratches, and chatter
What is an example of an occluding junction?
Zona Occludens (tight junction)
What are the Anchoring junction?
Zona adherens and maculae adherentes (desmosomes)
What zone of bone is positive for TUNEL staining (a marker of apoptosis)?
Zone of Calcification
What zone of bone does not stain for differentiation markers?
Zone of reserve cartilage
Actin filaments are linked most directly to the?
Zonula occudens and zonula adherens
Describe an Oblique cut.
an angled transverse cut
What is in the ECM of cartilage?
collagen, proteoglycans, and multiadhesive glycoproteins; solid gel-like consistency
What is the function of the Lysosome?
digestion of macromolecule
In ground bone fixation you?
remove organic material and finely grind the mineral matrix
In Decalcified fixation you?
remove the mineral, leaving behind the cells and organic matrix that can be stained with H&E
What is the function of Hyaline cartilage?
resistant to compression; cushioning; low-friction surface for joints; structural support; template for fetal skeleton, and further endochondral bone formation and growth
What is the function of the golgi apparatus?
sorting and packaging for secretion or intracellular transport; chemical modification of proteins
What is the function of Endocrine glands?
they secrete products (hormones) into connective tissue where they enter the bloodstrean.
What does the sarcomere consist of?
thin and thick myofilaments
What is the function of the Basal domain?
to Anchor cells to the underlying connective tissue