Term | Definition |
tissues | are groups of similar specialized cells that have a common function |
four types of tissue | epithelial, connective, muscle, nervous |
epithelial tissue (avascular - no direct blood supply) | covers surfaces and lines hollow organs and tubes in the body; protection, absorption, filtration, and excretion |
number of layers (epithelial) | simple - 1 layer of cells
stratified - more than 1 layer of cells |
shape of cells (epithelial) | squamous, cuboidal, columnar |
squamous | flat or "squashed"
nucleus appears flat in cell |
cuboidal | cube shape
cells are as tall as they are wide
nucleus is round and in center of cell |
columnar | column/rectangle shape
cells are taller than they are wide
nucleus is oval |
not all epithelial tissue fits into this simple classification system | pseudostratified epithelium, transitional epithelium (urinary bladder), glandular epithelium (endocrine sweat, oil gland) |
stratified squamous epithelium (hollow space) | protects underlying tissues because of its many layers
found in skin, mouth, esophagus, and vagina |
connective tissue (highly vascular, large nerve supply) | most abundant and widely distributed tissue type in the body |
functions of connective tissue | enclose and separates other tissues
connects tissues to one another (ligaments and tendons)
protects/support (bone)
storage (adipose tissue and bone)
cushions/insulates (adipose tissue)
transports (blood) |
areolar connective tissue (loose connective tissue) | liquid substance
found in dermis of skin, mucous membranes, space around organs |
adipose tissue (loose connective tissue) | stores a small amount of fat
found in deep to dermis, around organs |
dense regular connective tissue (dense connective tissue) | collagen fibers make this tissue very strong
makes up tendons and ligaments |
cartilage | cells are called chondrocytes
secrete the gel-like ground substance around themselves
no blood vessels |
hyaline cartilage | collagen fibers
found at ends of long bones, connects ribs to sternum, end of nose, embryonic skeleton |
elastic cartilage | come in pairs
maintains its shape after bending
found in external ear and the epiglottis |
fibrocartilage | strongest of 3
found in: intervertebral disks, pubic symphysis, meniscus of the knee |