TISSUES Flashcards
Group of cells with similar structure and function plus extracellular substance (matrix)
Tissues
Histology
Study of tissues
Location: Cover body ( linternal & external)
Ex. Skin, kidney, trachea, glands
Epithelial tissues
Characteristics of Epithelial Tissues
- Cells close together
- Form most glands
- Have free surface
- Basal Surface: Attaches epithelial cells to underlying tissues
Function of Epithelial Tissues
( Ex. Skin)
Protect
Function of Epithelial Tissue
(Ex. Skin keeps bacteria out)
Act as Barrier
Function of Epithelial Tissue
(Ex. Lungs and kidneys)
Diffusion and Filtration
Function of Epithelial Tissue
(Ex. Sweat glands)
Secretion
Function of Epithelial Tissue
(Ex. Small Intestine)
Absorption
Classification of Epithelial Tissues
According to number of cell layers and shape
Number of cell layers
Simple and Stratified
Cell Shape
Squamous, Cuboidal, Columnar, Transitional
Structure: 1 layer of cells
Simple Epithelium
Many layers of Cells
Stratified Epithelium
Structure: 1 layer of flat, Tile-like structures
Function: diffusion and filtration
Location: blood vessels, lungs, heart, kidneys
Simple Squamous
Structure: 1 layer of square-shaped cells
Function: Secretion
Locstion: glands, ovaries, kidneys
Simple Cuboidal
Structure: 1 lsyer of tall, narrow cells
Function: secrete mucus and absorption
Location: stomach, intestines, resp. Tract
Simple Columnar
Structure: 1 layer of tall, narrow cells appear stratified but isn’t
Function, secrete mucus and propel debris out of resp. Tract
Location: nasa cavity, trachea
Pseudostratified columnar
Structure: many layers of flat, tile-like cells
Function: protect and acts as a barrier
Location: skin, mouth, throat, esophagus
Stratified squamous
Structure: special type of stratifies epithelium changes shape
Function: hold fluids
Location: urinary blooder
Transitional
Surface not in contact with other cells
Free cell surfaces
Increase surface area
Ex. Small intestine
Microvilli
Move materials across cell’s surface
Ex. Trachea
Cilia
Free Cell Surfaces:
Produce mucus
Ex. Stomach
Goblet cells
Bind adjacent together
Ex. Intestines
Tight junctions
Mechanical links that bind cells
Desmosomes
Structures that secrete substances onto a surface, into a cavity, or into blood
Glands
Glands with ducts
Ex. Sweat or coil glands
Exocrine glands
Glands with no ducts
Ex. Thyroid, thymus, pituitary glands
Endocrine gland
- Cells far apart
- Contain large amounts of extracellular matrix
Connective Tissues
What does Extracellular matrix contain?
Protein fibers
Ground substance (protein & sugar)
Type of Protein Fiber:
Look like ropes and are flexible but resist stretching
Collagen fiber
Type of Protein Fiber:
Supporting network that fills spaces between organs and tissues
Reticular fibers
Type of protein fiber:
Recoil after being stretched
Elastic fiber
Functions of Connective Tissue
- Enclose and Separate
- Connect Tissues
- Support and Movement (bones)
- Storage (bones store calcium)
- Transport ( blood)
Connect bone to muscle
Tendons
Connect bone to bone
Ligaments
Type of Ordinary Connective Tissue
Location: between organs, muscles, glands, skin
Structure: Collagen fibers far apart
Function: support and protect
Loose
Type of Ordinary Connective Tissue
Location: tendons, ligaments, skin
Structure: collagen fibers packed close together
Function: connect and withstand pulling forces
Dense
Type of Ordinary Connective Tissue
Location: Underskin and around organs
Structure: collagen and elastic fibers, cells filled with lipids
Functions: storage and insulste
Adipose
- type of connective tissue
- composed of chondrocytes
- contain collagen
- withstand compression
- provides support, flexibility, strength
Cartilage
Type of Cartilage:
Location: covers ends of bones
Structure: some collagen fibers
Function: reduces friction
Hyaline Cartilage
Type of Cartilage:
Location: between vertebra
Structure: lots of collagen fibers
Function: can withstand compression
Fibrocartilage
Type of Cartilage:
Location: ear and tip of nose
Structure: elastic fiber
Function: can recoil
Elastic cartilage
- hard connective tissue
- composed of osteocytes
Bone
Types of bones
Compact and Spongy
- liquid connective tissue
- Erythrocytes, leukocytes, platelets
- transport food, oxygen, waste, hormones
Blood
Substitution of dead cells for viable cells
Tissue Repair
Cells of same type develop (no scar)
Regeneration
Cells of a different type develop (scar)
Replacement
