Lecture 2- Tissues

Exam 1 Material

75 trillion

There are over __________ cells in the body

epithelial, connective, muscular, neural

what are the four primary tissue types in the body?

cellularity, polarity, avascularity

what are the characteristics of epithelial tissue?

apical

exposed surface of epithelial tissue

basal

Attached surface

Epithelioid cells

Epithelial cells without a free surface

polarity

is the term that is in reference to the structural and functional difference between apical and basal surfaces

stratified epithelia

where are epithelioid found?

basal lamina

what is the basal epithelia layer attached to?

protection, control of permeability, sensation, secretion

functions of epithelial tissue

microvilli

– Increases surface area for absorption of material
– Found on apical surface of cells of the urinary and digestive tracts

stereocilia

– Long microvilli, commonly found in the inner ear and male reproductive tract

ciliated epithelium

– Moves substances over the apical surface
– Found lining the respiratory tract

intercellular connections, attachment to basal lamina, self perpetuated maintenance

What 3 factors are involved in maintaining integrity of the epithelium?

basal lamina and reticular lamina

what are the 2 layers of the basement membrane?

stem cells near the basal lamina

how are epithelia cells replaced/renewed

simple epithelium

Epithelium has only one layer of cells

stratified epithelium

Epithelium has two or more layers of cells

areas with chemical or mechanical stresses

where is stratified epithelium found?

in protected areas like internal compartments

where is simple epithelium found?

Squamous

Cells are relatively flat in appearance

Cuboidal

Cells are shaped like cubes

Columnar

Cells are longer than they are wide

reduce friction and absorb and secrete material

function of simple squamous epithelium

lining of body cavities, heart, and blood vessels

where is simple squamous epithelium found?

surface of skin lining of mouth, anus, esophagus, vagina

where is stratified squamous epithelium found?

protection, can be keratinized

function of stratified squamous epithelium

secretion and absorption

function of simple cuboidal epithelium

secretion and absorption

function of stratified cuboidal epithelium

thyroid gland, ducts, kidney tubules

where is simple cuboidal epithelium found?

sweat glands

where is stratified cuboidal epithelium found?

lining stomach, intestines, gallbladder, uterine tubes, and collecting ducts of the kidneys

where is simple columnar epithelium found?

Pharynx, epiglottis, anus, mammary glands, salivary glands, and urethra

where is stratified columnar epithelium found?

protection

function of stratified columnar epithelium

secretion, absorption, protection

function of simple columnar epithelium

Pseudostratified ciliated columnar epithelium

epithelia with one layer but nuclei situated at different levels

nasal cavity, trachea, bronchi

where is pseudostratified epithelia found?

transitional epithelium

-Consists of many layers
-Consists of a combination of cuboidal and “oddly” shaped cells

Urinary bladder, renal pelvis, and ureters

where is transitional epithelium found?

extensive stretching

function of transitional epithelium

endocrine glands

secretions directly into the bloodstream

exocrine glands

Secretions travel through ducts to the epithelial surface

goblet cells

glandular epithelia cells found in the trachea that secrete mucous

tubular

gland where cells are arranged in a tube

alveolar or acinar gland

gland where cells form a blind pocket

tubuloalveolar or tubuloacinar gland

gland that combines tubular and alveolar

eccrine secretion

-secretion by exocytosis
-found in salivary glands

apocrine secretion

▪ Shedding of the apical portion of the cell during secretion
▪ Found in mammary glands

holocrine secretion

▪ Cell bursts apart in secretion
▪ Found in sebaceous glands

specialized cells, extracellular protein fibers, matrix

what are the three main components of connective tissue?

the term for the extracellular component of CT made of protein fibers and ground substance

what is matrix?

structure, transportation, protection, connection, energy storage, defense

functions of CT

CT proper, fluid CT, supporting CT

what are the 3 major categories of CT

CT proper

Has a matrix of fibers (loose fibers and dense fibers)

fluid CT

Has a matrix of liquid (blood and lymph)

supporting CT

Has a matrix of fibers and, in some cases, insoluble calcium salts

fixed and wandering cells

what are the two classes of connective tissue proper cells?

help fight infection or repair tissue damage

function of wandering cells

collagen, reticular, elastic

what are the three types of fibers associated with connective tissue?

collagen

fibers that are designed in such a manner to develop tensile strength, which is the ability to resist tension

areolar, adipose, and reticular tissue

what are the loose connective tissues?

dense regular, dense irregular, elastic

what are the dense connective tissues?

connect skin to muscle

function of areolar tissue

Cushion and insulation

function of adipose tissue

support

function of reticular tissue

tendons, aponeuroses, ligaments, elastic tissue

where is dense regular CT found?

tendons

connect muscle to bone

Aponeuroses

connect muscle to muscle or cover entire muscle

ligaments

connect bone to bone

elastic ligaments

contain elastic fibers allowing for a modest amount of stretching

elastic tissue

stabilizes the vertebrae

chondrocytes

main cell type found in cartilage

lacunae

pocket where chondrocytes reside

appositional growth (thickness) and interstitial growth (height)

what 2 types of growth is cartilage involved in?

lacunae

where do bone cells reside?

solid matrix of calcium phosphate

what makes up bone?

lamellae

concentric rings found in bone

Hyaline cartilage

– Specialized CT that provides flexible support
– Reduces friction

elbow, knee, trachea, ribs/sternum

where is hyaline cartilage found?

elastic cartilage

specialized CT for flexible support

ear, epiglottis, auditory tube

where is elastic cartilage found?

fibrous cartilage

specialized CT to resist compression and absorb shock

knee pads, spinal vertebrae, pubic symhsis

where is fibrous cartilage located?

central canal

where is vascularization found within bones?

compact bone

bone with blood vessels are trapped in the matrix

spongy bone

bone where blood vessels are not trapped in the matrix

periosteum

covers bone surfaces

blood and lymph

what are the fluid connective tissues?

nerve and muscle sheaths

where is dense irregular CT found?

provide strength and form fibrous capsule around organs

what is the function of dense irregular CT?

epithelial and connective

what types of tissue combine to form membranes?

mucous, serous, cutaneous, synovial

what are the 4 types of membranes?

pleura

serous membrane that lines the lungs

Peritoneum

serous membrane that lines the peritoneal cavity (all other organs)

pericardium

serous membrane that lines the heart

transudate

serous fluid associated with membranes that allows for gliding

lamina propria

the connection of the epithelium with underlying tissue

barrier against pathogen entry, keep epithelial surfaces moist

what is the function of mucous membranes?

line body cavities

what is the function of serous membranes?