Zusammenfassung der Ressource
unit 2: tissues
- Epithelial
- Function → protection, secretion, absorption, excretion Location
→ covers body surface, covers and lines internal organs,
compose glands Characteristics → lack blood vessels, cells
readily divide, cells are tightly packed together.
- basement membrane : anchors epithelium to connective tissue.
- Basement membrane : anchors epithelium to connective tissue
- TYPES OF EPITHELIAL CELLS
- Simple Squamous
- lines blood vessels and air sacks of the lungs
- Simple Cuboidal
- Simple Columnar
- Stratified squamous
- Stratified cuboidal
- lines ducts and glands.
- Stratified columnar
- <-epithelial tissue
- Connective
- Function → bind, support, protection, fill space , store fat, produce blood cells Location → widely
distributed throughout the body Characteristics → Mostly have a good blood supply, cells are farther
apart than epithelial cells, extracellular matrix in between
- Major types of cells
- Fibroblasts :produce collagen and elastic fibers
- Macrophages are phagocytes (“eat cells”)
- Connective tissue fibers
- Collagen fibers have a great tensile strength.
- Elastic fibers are composed of elastin and are stretchy.
- Categories of connective tissues
- Loose Connective Tissue
- Areolar → forms thin membranes between organs and binds them together. Found beneath the skin and
surrounds organs Adipose → stores fat, cushions, and insulates. Found beneath the skin; in certain
abdominal membranes; and around the kidneys, heart, and various joints. Reticular → thin branched
reticular fibers. Supports the walls of the liver and spleen.
- Dense Connective Tissue
- Dense Regular → strong collagen fibers that bind structures as parts of tendons and ligaments.
Dense Irregular → thicker, randomly distributed collagen fibers and is found in the dermis.
Elastic → elastic fibers that make up hollow internal organs like the lungs and blood vessels.
- Cartilage
- provides support Consists of fibers and a gel-like substances Lacks a direct blood supply, so it is slow to
heal Found at the ends of various bones; in the ear; in the larynx; and in the pads between the bones of
the spinal column, pelvic girdle, and knees Bone → matrix consists of mineral salts and collagen.
Compact & spongy bones. Heals rapidly Blood → Composed of cells suspended in fluid. Produced in the
tissue of hollow parts of certain bo
- Reticular fibers are fine collagen fibers.
- Mast cells may release heparin and histamine
- connective tissue ->
- Muscle
- Function → movement Location → attached to bones, in the walls of hollow internal organs, heart Characteristics → Able to
contract in response to specific stimuli
- Nervous
- Function → movement Location → attached to bones, in the walls of hollow internal organs, heart
Characteristics → Able to contract in response to specific stimuli
- Nervous
- Function → conduct impulses for coordination, regulation, integration, and sensory reception
Location → brain, spinal cord, nerves Characteristics → cells communicate with each other and
other body parts
- nervous tissue ->