Midterm 1 - Tissues, Bones, Muscles Flashcards
Primary Tissue Types
Epithelial, Connective, Muscular, Nervous
Epithelial Tissue Functions
-provide physical protection
-control permeability
-provide sensation (innervated by sensory nerves)
-produce secretions
Epithelial Tissue Characteristics
-Cellularity (bound close together, no intercellular space)
-Polarity
-Attachment (basal layer attached to basal lamina)
-Avascularity (no blood vessels)
-Regeneration (stem cells)
Microvilli
increase surface area and absorption of material
Cilia
Moves substance over the apical surface
Simple Epithelia
-one layer of cells
-nuclei at approx. the same level in each cell
-found in protected areas (ie. internal compartments)
Stratified Epithelia
-two or more layers
-found where there is chemical or mechanical stresses
Shapes of Epithelia
Squamous, Cuboidal, Columnar
Squamous Epithelia
cells are relatively flat
Cuboidal Epithelia
Cells shaped like cubes
Columnar Epithelia
Cells are longer than they are wide (shaped like columns)
- can perform more functions than squamous & cuboidal (secretion, mechanisms, storage, etc.)
Simple Squamous Cells
Alveoli in lungs
-make it easy for exchanges and movement
-very delicate
-Lines body cavities, blood vessels, heart chambers, sites of gas exchange
-reduces friction, absorbes and secretes material
Simple Cuboidal Cells
-Kidney tubules, Thyroid gland, ducts
-Secretion, absorption, very limited protection
Simple Columnar Cells
Lining digestive tract, stomach, intestines, uterine tubes, collecting ducts of kidneys
-Secretion, absorption, protection
Stratified Squamous Cells
Skin
-renew from bottom, don’t need many proteins
