biol 227 Exam Study Material with
Complete Solutions
Four types of tissues
•Epithelial
•Connective
•Muscle
•Nervous
Characteristics of Epithelial Tissue
•Cellularity
•Composed of tightly packed cells
•Cells > extracellular matrix
•Polarity
•Apical surface
•Basal surface
•Basement Membrane Attachment
•3 noncellular layers
•Exist between epithelium and underlying CT
•Function: glue, selective barrier
•High regeneration capacity
•High rate of cell division
•Frequent mitosis of basal cells
•Avascularity
•No blood vessels
,•Extensive innervation
•Two types
•Covering and lining
Glandular
functions of epithelial tissue
physical protection, selective permeability, secretions, sensations
Classification of Epithelial Tissue Simple
•Single layer
•All cells contact basement membrane
•Function: filtration, absorption, and secretion
•Low protective function
Classification of Epithelial Tissue Stratified
•Multiple layers
•Function: more structural support or protection
•Basal cells continuously regenerate
Classification of Epithelial Tissue Pseudostratified
•Single layer, appears multi-layered
•Nuclei at different levels
•All cells contact basement membrane, but not all cells reach apical surface
Classification of Epithelial Tissue Squamous
•Flat, wide, irregularly shaped cells
•Flat central nucleus
Classification of Epithelial Tissue Cuboidal
•Even dimensions (equal height and width)
•Spherical central nucleus
,Classification of Epithelial Tissue Columnar
•Tall, thin cells
•Oval nucleus
Classification of Epithelial Tissue Transitional
•Apical cells change shape in response to stretch
Simple Squamous Epithelium
Structure:
•Single layer of flattened cells
Function:
•Rapid diffusion and filtration, some secretion
Location:
•Alveoli, vessel linings, serous membranes
•Endothelium: lining vessels
•Mesothelium: serous membranes
Simple Cuboidal Epithelium
Structure:
•Single layer of cells with even dimensions
Function:
•Absorption and secretion
Location:
•Thyroid gland follicles, ovary surface, kidney tubules, secretory ducts
Ciliated Simple Columnar Epithelium
Structure:
, •Ciliated apical surface
•Goblet cells – secrete mucin
Function:
•Mucin secretion
•Mucus movement (via cilia)
•Oocyte movement (via cilia)
Location:
•Lining of air passageways and uterine tubes
Nonciliated Simple Columnar Epithelium
Structure:
•Microvilli – brush border
•Goblet cells – secrete mucin
Function
•Absorption and secretion
Location:
•Most of GI tract lining
Ciliated Pseudostratified Columnar Epithelium
Structure:
•Ciliated apical surface
•Goblet cells – secrete mucin
Function:
•Protection
•Mucin secretion and movement
Complete Solutions
Four types of tissues
•Epithelial
•Connective
•Muscle
•Nervous
Characteristics of Epithelial Tissue
•Cellularity
•Composed of tightly packed cells
•Cells > extracellular matrix
•Polarity
•Apical surface
•Basal surface
•Basement Membrane Attachment
•3 noncellular layers
•Exist between epithelium and underlying CT
•Function: glue, selective barrier
•High regeneration capacity
•High rate of cell division
•Frequent mitosis of basal cells
•Avascularity
•No blood vessels
,•Extensive innervation
•Two types
•Covering and lining
Glandular
functions of epithelial tissue
physical protection, selective permeability, secretions, sensations
Classification of Epithelial Tissue Simple
•Single layer
•All cells contact basement membrane
•Function: filtration, absorption, and secretion
•Low protective function
Classification of Epithelial Tissue Stratified
•Multiple layers
•Function: more structural support or protection
•Basal cells continuously regenerate
Classification of Epithelial Tissue Pseudostratified
•Single layer, appears multi-layered
•Nuclei at different levels
•All cells contact basement membrane, but not all cells reach apical surface
Classification of Epithelial Tissue Squamous
•Flat, wide, irregularly shaped cells
•Flat central nucleus
Classification of Epithelial Tissue Cuboidal
•Even dimensions (equal height and width)
•Spherical central nucleus
,Classification of Epithelial Tissue Columnar
•Tall, thin cells
•Oval nucleus
Classification of Epithelial Tissue Transitional
•Apical cells change shape in response to stretch
Simple Squamous Epithelium
Structure:
•Single layer of flattened cells
Function:
•Rapid diffusion and filtration, some secretion
Location:
•Alveoli, vessel linings, serous membranes
•Endothelium: lining vessels
•Mesothelium: serous membranes
Simple Cuboidal Epithelium
Structure:
•Single layer of cells with even dimensions
Function:
•Absorption and secretion
Location:
•Thyroid gland follicles, ovary surface, kidney tubules, secretory ducts
Ciliated Simple Columnar Epithelium
Structure:
, •Ciliated apical surface
•Goblet cells – secrete mucin
Function:
•Mucin secretion
•Mucus movement (via cilia)
•Oocyte movement (via cilia)
Location:
•Lining of air passageways and uterine tubes
Nonciliated Simple Columnar Epithelium
Structure:
•Microvilli – brush border
•Goblet cells – secrete mucin
Function
•Absorption and secretion
Location:
•Most of GI tract lining
Ciliated Pseudostratified Columnar Epithelium
Structure:
•Ciliated apical surface
•Goblet cells – secrete mucin
Function:
•Protection
•Mucin secretion and movement
