Term | Definition |
the correct order for the standard preparation of a histological specimen. | 1) Fixation, (2) sectioning, (3) staining |
4 Types of Tissues | 1) Epithelial for covering
2) Connective for support
3) Muscle for movement
4) Nervous for control |
2 types of Epithelial Tissue/Epithelium | 1) Covering and lining epithelium
• e.g., separates cells of bladder wall from urine
2) Glandular Epithelium
• Forms glands of the
body |
Functions of Epithelium
(PA FESS) | 1) Protection
• from injury, bacterial invasions
2) Absorption
• in digestive tract, kidneys
3) Filtration
• kidneys
4) Excretion
• kidneys
5) Secretion
• kidneys, glands
6) Sensory reception
• nerve endings |
Special Characteristics of Epithelium
(CSP CAR) | 1) Cellularity
2)Specialized contacts
3)Polarity
4)Connective Tissue (supported by)
5)Avascular but innervated
6)Regeneration |
tight junctions | Form the closest contact between adjacent cells known in nature. Found in the apical region around the cell's circumference. |
Desmosomes | serve localized adhesive function and connect the plasma membrane to intermediate filaments in the cytoplasm. The connections are especially important in stratified epithelium. |
gap junctions | 3) Gap junctions consist of intercellular channels in the plasma membrane of adjacent cells. Small molecules can diffuse across the channel and into the cytoplasm of the other cell. |
Adherens junctions | 4) Adherens junctions play a role in intracellular adhesion and the interaction of the actomyosin cytoskeleton with the plasma membrane. |
Polarity | Apical and Basal surfaces differ in structure and
function |
Apical Surface | – surface exposed to body exterior or
cavity of an internal organ |
Basal Surface – | lower attached surface |
Supported by Connective Tissue | Basement membrane |
Basement
Membrane | Basal Lamina (top)
Reticular Lamina (bottom) |
Avascular but innervated
How do these cells maintain nutrients? | Nourished by substances from blood vessels in the
basal connective tissue |
Regeneration in epithelial tissue | High regeneration rate since they are exposed to
external substances/surfaces and damaged. |
Classification of Epithelium (two names) | First Name
Simple OR Stratified
Second Name
Squamous OR Cuboidal OR Columnar |
Transitional Epithelium | In urinary organs, when organs are filled with
urine, cells flatten and become squamous-like |
Glandular Epithelium Classification | Classification
Unicellular or Multicellular
Endocrine or Exocrine |
Unicellular | Scattered within
epithelium |
Multicellular | Inward or outward
growth from
epithelium
Have ducts = tubelike connections to
the epithelium |
Endocrine | Duct-less glands
Secretion =
Hormones |
Exocrine | Glands that have
ducts
Secretions =
mucous, sweat, oil,
saliva, bile, etc. |
Tissues definition | group of cells that are similar in structure and
perform a common function |
Connective Tissue Characteristics | 1) Common Origin
o 2) Degrees of Vascularity
o varies
o 3) Extracellular matrix
o largely non-living material which
separates living cells
o bear weight, withstand tension,
endure abuses |
Structure of Connective Tissue | Ground Substance
Fibers (= support)
• Collagen
• Elastic
• Reticular
Cells |
Ground Substance 3 major parts | Tissue Fluid
Cell Adhesion Proteins
Proteoglycan Network |
Connective Tissue Functions | o Binding and support (cartilage, bone)
o Protection (fat)
o Insulation (fat)
o Transportation (blood) |
The 4 types of connective tissue: | 1) Connective tissue proper
Loose
Dense
2) Cartilage
3) Bone
4) Blood |
Loose CT - Areolar | All three fiber types
High hyaluronic acid
content
Most widely distributed
Acts like packing material
Edema
Associated with most
epithelial membranes |
Loose CT - Adipose | Adipose
Cells: adipocytes
Peripheral nuclei
Functions:
Fat storage (energy)
Brown fat
Insulates
Cushions |
Loose CT Reticular | Only reticular
fibers
Found in:
Lymph nodes
Spleen
Bone marrow |
Dense CT for? | Provide strength and elasticity |
Dense Regular (Fibrous) CT | Collagen fibers
Locations: tendons &
ligaments
Resists tensions in primarily
one direction |
Dense Irregular CT | Fibers in many
directions
Resists tensions in many
directions
Found:
Below skin
Sheath around cartilage
and bone
Capsule around internal
organs |
Cartilage | Avascular - no blood vessels
Lack innervation - no nerves
Cells
Found in holes called lacunae
Chondroblasts (during cartilage formation)
Chondrocytes (mature) |
Chondroblasts | (during cartilage formation) |
Chondrocytes | mature |
Cartilage 3 Major Types: | Hyaline
Elastic
Fibrocartilage |
Hyaline | Most abundant
Fibers: collagen (not
visible)
Location
Tip of nose, fetal
skeleton, and many
more |
Elastic | Elastic fibers
Recoil after
bending
Pinna
(external ear)
& epiglottis |
Fibrocartilage | Compressible
Intervertebral
discs, knee |
Bone Functions | Support
Leverage for movement
Protection
Hematopoiesis |
Bone Features | Cells (osteoblasts/osteocytes) in
a hard matrix of minerals and
collagen |
Bone Types | Spongy bone
Compact bone |
Blood | Cells and cell fragments in a liquid matrix (plasma) |
Leukocytes | = white
blood cells (WBCs)
Fight disease |
Erythrocytes | = red
blood cells (RBCs)
Transport respiratory
gases (O2) |
Platelets | (cell fragments)
Clotting mechanisms |
Plasma | Transports nutrients, wastes (urea,CO2, hormones) |
4 Blood parts | Leukocytes
Erythrocytes
Platelets
Plasma |
Connective Tissue Hierarchy | 1) Connective Tissue Proper
a. Loose CT
1. Areolar
2. Adipose
3. Reticular
b. Dense CT
1. Dense regular
2. Dense irregular
2) Cartilage
a. Hyaline
b. Elastic
c. Fibrocartilage
3) Bone
4) Blood |
Muscle Tissues | High rate of
metabolic activity
Highly vascular
for O2
and nutrients
Specialized for
contraction resulting
in movement |
Muscle Tissue Three Major Types | Skeletal
Cardiac
Smooth |
Skeletal Muscle | Attached to bones
Voluntary movement
Appear striated & multinucleate
Peripheral nuclei |
Cardiac Muscle | Involuntary movement
Contraction w/in myocardium (heart wall)
Appear striated w/ large nuclei
Branching |
Smooth Muscle | No visible striations
Involuntary movement
Walls of hollow organs
Digestive system, blood vessels |
Nervous Tissue | Specialized for
recognizing
environmental changes
(stimuli)
act as receptors
Integrate sensory inputs
and motor outputsNervous Tissue
Cells:
Neurons
conduct
information
Neuroglia
supporting cells
protect, insulate,
sup |
Epithelial Membranes | Consist of epithelial tissue
and CT |
3 types of Epithelial Membranes | Serous membranes
Cutaneous membranes
Mucous membranes |
Serous Membranes | Mesothelium & areolar CT
Secrete serous fluid
(lubricates & cushions)
Visceral & parietal serosae
line 3 body cavities:
Pericardium
Pleura
Peritoneum |
Cutaneous Membranes | Forms skin
Consists of:
Stratified squamous
epithelium
(epidermis)
Connective tissue
(dermis)
Areolar CT
Dense irregular CT |
Mucous Membranes | Lines body cavities open
to the outside
Digestive system
Respiratory system
Reproductive tract
Urinary tract
“Wet” membranes
Bathed in secretions –
mucous, urine |
Intercalated discs | Intercalated discs are microscopic identifying features of cardiac muscle. Cardiac muscle consists of individual heart muscle cells (cardiomyocytes) connected by intercalated discs to work as a single functional organ or syncitium. |
Why are histological sections stained? | To enhance contrast |
Polarity is a property of all normal epithelial tissues. T or F | True |
The role of microvilli is to: | increase surface area. Microvilli are small finger like projections that greatly increase the surface area of certain epithelial tissues. They are especially important in epithelial tissues that have a role in absorption and secretion. |
Stratified squamous for | Protection from wear and tear |
Simple squamous for | Filtration |
Simple cuboidal for | Secretion and absorption |
Transitional for | Stretching |
What is the role of an exocrine gland? | To secrete substances onto body surfaces. |
You observe a multicellular gland with branched ducts. Interestingly, the secretory unit of the gland also has a sac-like appearance. What type of gland would this most likely be? | A compound alveolar exocrine gland |
A sebaceous (oil) gland of the skin must completely rupture to release its secretory products. Thus, this type of gland is considered to be a: | holocrine gland |
_______________ are important and common unicellular exocrine glands. | Goblet cells - Mucous cells and goblet cells are common and important examples of unicellular exocrine glands. |
What is true of mucin? | It is a complex glycoprotein found in mucus. Mucin is a complex glycoprotein that can be dissolved in water to form mucus. In humans, all unicellular exocrine gland produce mucin. |
Collagen is: | a fibrous protein that provides tensile strength to certain connective tissues. |
Osteoblasts | Bone formation |
Hematopoietic stem cells | Blood cell formation |
Chondroblasts | Formation of cartilage |
Fibroblasts | Formation of fibers |
White blood cells | Body's defense system |
Macrophages: | are phagocytic cells. |
What kind of classification isadipose tissue | a loose connective tissue. |
The skin is a ____________ membrane | cutaneous |
The first step in tissue repair is: | inflammation |
All of the body's organs are derived from three primary germ layers. Which of the primary germ layers can produce epithelial tissues? | Ectoderm, endoderm and mesoderm can all give rise to epithelial tissues. |
Fibrosis | Fibrosis involves proliferation of fibrous connective tissue called scar tissue. |
Inflammation | Inflammation is the first reaction to trauma that allows later events of repair to occur. |
Adhesions are areas where new scar tissue grows and connects adjacent organs after surgery. T or F | True. Adhesions often cause problems after surgery by preventing normal functioning of internal organs. |
epithelium | An epithelium is a sheet of cells that covers a body surface or lines a body cavity. |
Brown adipose tissue | Brown adipose tissue, found only in babies, contains many lipid droplets and numerous mitochondria that use lipid fuel to heat the bloodstream and warm the infant. |
Endocrine glands | Endocrine glands secrete their products into the bloodstream rather than on an epithelial surface. |
Epithelium vascularity? | Epithelium is avascular (lacking blood vessels) and receives nutrients from capillaries in underlying connective tissues. |
Epithelial tissue secretes the basal lamina region of the basement membrane. T or F | True. The basal lamina region of the basement membrane is a thin, non-cellular sheet, consisting of proteins secreted by epithelial tissue cells. |
inflamation is... | Inflammation is a nonspecific, local response that limits damage to the injury site while the immune response destroys particular infectious microorganisms and foreign molecules at the site of infection and throughout the body. |
Microvilli | Microvilli maximize the surface area across which small molecules enter or leave cells and are NOT involved in the movement of materials across the surface of a cell. |
____ forms most of the body's glands. | Epithelial tissue forms most of the body's glands. |
Mucosa lines... | Mucosa lines the inside of hollow internal organs that open to the outside of the body. |
______ lines closed cavities. | Mesothelium lines closed cavities. |
A _______, which lines the ventral body cavity walls and viscera, consists of a ____________ lying on a thin layer of ________ tissue. | A serous membrane, which lines the ventral body cavity walls and viscera, consists of a simple squamous epithelium lying on a thin layer of areolar connective tissue. |
T or F With increasing age, epithelia become thinner and more easily damaged. | TRUE- As we age, metabolism and tissue regeneration slows. |
As we age the amount of collagen in the body declines, making tissue repair less efficient. | True - The body produces less collagen as we age, adversely affecting tissue repair. |
Regeneration is ... | Regeneration is the replacement of destroyed tissue with the same kind of tissue. |
____ is made of many osteons. | Bone is made of many osteons. |
Fibrosis | During the process of tissue repair, fibrosis involves the proliferation of a fibrous connective tissue called scar tissue. |
Embryonic ectoderm develops into which of the following major tissue types? | Epithelial tissue and nervous tissue
Nervous tissue develops solely from embryonic ectoderm, while epithelial tissues develop from ectoderm, endoderm, and mesoderm embryonic tissue. |
What type of tissue forms tendons? | Dense regular connective tissue |
The basement membrane is located between which tissue types? | Epithelial and connective
Epithelial tissue secretes the superficial basal lamina region of the basement membrane, whereas connective tissue produces the deeper reticular layer of the basement membrane. |
This type of epithelial tissue lines the interior of blood vessels. | Endothelium - A simple squamous epithelial tissue lines the interior of blood vessels. |
This unicellular gland is associated with mucus production. | Goblet cells, located between columnar epithelial cells, function in producing the protein mucin, which, when combined with water, forms mucus. |
Which apical epithelial cell structures functions in the movement of materials across the surface of the cell? | The cilia on an epithelium bend and move in coordinated waves, pushing mucus and other substances over the epithelial surface. |
What best describes a squamous-shaped cell? | Squamous cells are flattened and scale-like. |
Which of the following epithelial tissue types is best adapted for the rapid transport of materials across its membranes? | Simple squamous epithelial tissue, composed of a single layer of flattened cells, occurs wherever small molecules must pass through a membrane quickly. |
Does the areolar connective tissue provide movement of body parts | No, areolar connective tissue holds body fluids, stores nutrients, supports and binds other tissues, and defends the body against infection, movement of body parts is a task performed by the three different types of muscle tissue. |
does epithelial tissue have a function of control? | No, Epithelial tissue functions in protection, secretion, ion transport, and filtration, but control is the primary responsibility of nervous tissue. |
What epithelial tissue lines the majority of the digestive tract? | Simple columnar epithelial tissue lines most of the digestive tract, from the stomach to the anus. |
What epithelial tissue provides the greatest amount of protection? | Stratified squamous is the thickest form of epithelial tissue and is composed of multiple layers of flat cells. |
What is the proper sequence of tissue repair? | Tissue damage, blood clotting, scab formation, organization, fibrosis, regeneration. |
What are the functional characteristics of epithelial tissue? | Secretion, protection, absorption, filtration |
Mucous that protects your stomach lining is secreted by a specialized type of: | simple columnar epithelial cell. Goblet cells are simple columnar epithelial cells. |
A type of connective tissue that provides primary support and protection for body structures is | osseous tissue. |
Reticular connective tissue | is found in soft tissues and does not provide primary support. |
Which type of tissue is found on the surface of the skin? | The epidermis is stratified squamous epithelium. |
Artifacts | are the minor distortion seen in cells from staining procedures. |
Microvilli are found on the ________ of the cell. | Microvilli are present on the free surface of the cell, which is its the apical. |
The presence of keratin provides a tough protective characteristic to: | stratified sqamous epithelium |
merocrine gland | A merocrine gland excretes its secretion by exocytosis without rupturing the cell. |
Connective tissue arises from which embryonic tissue? | Mesoderm |
ectoderm gives rise to _________ | Ectoderm gives rise to nervous tissue. |
A flat sheath-like tendon that connects muscle to bone is known as: | An aponeurosis is a flat sheath-like tendon that connects muscle to muscle or bone. |
Blood is considered a connective tissue because: | Blood is considered a connective tissue because it arises from mesenchymal tissue. |
The stroma of most solid organs is composed of: | reticular connective tissue. |
___________ tissue serves as a packing material between tissues. | Areolar connective tissue serves as a packing material between tissues. |
Walls of the air sacs of the lungs and lining blood vessels | Simple squamous |
Upper respiratory tract cell type | Pseudostratified ciliated columnar |
Walls of smallest ducts of glands and kidney tubules | Simple cuboidal |
Lines the urinary bladder | Transitional |
Skin | Keratinized stratified squamous |
Mammary glands composed of? | Compound alveolar |
Salivary glands composed of? | Compound tubuloalveolar |
Intestinal glands composed of? | Simple tubular |
Sebaceous glands composed of? | Simple branched alveolar |
Collagen fibers | The strongest and most abundant fibers, they allow connective tissues to resist tension |
Reticular fibers | These short branching fibers cluster into delicate networks and have the ability to glide freely across one another whenever the network is pulled, allowing give |
Elastic fibers | These long, thin, branching fibers form wide networks within the extracellular matrix and possess the ability to stretch and then return to their original length |
Mast cells | Secrete histamine |
Plasma cells | Produce antibodies |
Fibroblasts | Produce collagen, elastic, and reticular fibers |
Macrophages | Phagocytic cells that engulf foreign matter |
Adipocytes | Store fat molecules |
Adipose location | Hypodermis; in mesenteries; surrounding kidneys; posterior to eyeballs |
Elastic cartilage location | Supports external ear, epiglottis |
Dense regular connective tissue location | Ligaments; tendons; aponeuroses |
Fibrocartilage location | Intervertebral discs; pubis symphysis; menisci of knee joint |
Reticular connective tissue location | Bone marrow; spleen; lymph nodes |
Osteoblast | Bone-producing cell |
Plasma | Liquid portion of blood |
Chondrocyte | . Cartilage-producing cell |
Extracellular matrix | Non-living material located between the cells of a connective tissue |
Reticular cell | Type of fibroblast |
Cutaneous membrane | Covers the outer surface of the body |
Mucous membrane (mucosa) | Lines the inside of hollow organs that open to the body's exterior |
Serous membrane (serosae) | Lines the ventral body cavity walls and covers the ventral body cavity viscera |
Skeletal muscle tissue | Striated; multinucleated cells; long, large, cylinder-shaped cells |
Smooth muscle tissue | No striations; spindle-shaped cells; uninucleated cells |
Cardiac muscle tissue | Striated; branching cells; intercalated discs; generally uninucleated cells |
Hyaline cartilage location | Forms embryonic skeleton and covers the ends of long bones |
Dense regular connective tissue location | Primary tissue of ligaments and tendons |
Dense irregular connective tissue location | Primary tissue of the dermis |
Connective tissue proper | Loose connective tissue (areolar, adipose, and reticular); dense connective tissue (dense regular, dense irregular, and elastic) |
Cartilage | Stands up to both tension and compression; tough and flexible, providing resilient rigidity |
Bone tissue | Supports and protects body structures; stores fat; synthesizes blood cells |
Blood | Most atypical connective tissue; extracellular fibers are soluble protein molecules found in liquid plasma; abundant extracellular matrix |
Cutaneous membrane | Provides protection for outer surface of body |
Mucous membrane | Provides secretions that lubricate and protect areas that open to the outside of the body |
Serous membrane | Provides secretions for lubrication of organs enclosed within the body cavities |
Fibroblast | Produces materials in connective tissue proper |
Chondroblast | Produces extracellular matrix of cartilage |
Osteoblast | Produces extracellular matrix of bone |
Hematopoietic stem cell | Produces blood cells |
Epithelial tissue embryonic origin | Ectoderm, endoderm, and mesoderm |
Connective tissue and muscle tissue embryonic origin | Mesoderm |
Nervous tissue embryonic origin | Ectoderm |
Very good at regenerating | Epithelial tissue, bone, loose connective tissue, and blood |
Moderate regenerating capacity | Smooth muscle and dense connective tissue |
Skeletal muscle and cartilage | Poor regenerating capacity |
No useful regeneration | Nervous tissue and cardiac muscle |