Chp4 tissue level Flashcards
(98 cards)
What are tissues?
•collection of specialized cells and cell products that perform a limited number of functions
What is the study of cells?
•histology
How many types of tissue is there? And name them
•4
- Epithelial Tissue
- Connective Tissue
- Muscular Tissue
- Nervous Tissue
Where can you find Epithelial Tissue?
• Covering exposed surfaces, lining internal passageway and chambers, and forming glands
Where can you find connective tissue?
- filling internal spaces,
- provides structural support for other tissues
- transports material w/in the body
- storing energy (triglycerides)
Where can you find Muscle Tissue?
- specializes in contraction
- skeletal muscle
- muscle of the heart
- muscular walls of hollow organs
What does Neural Tissue do?
•carry information in form of electrical impulses
What does Epithelial tissue include?
- epithelia
* glands
What is Epithelia?
- Layers of cells that cover internal or external organs
- Skin, blood vessels
- Lining digestive, respiratory, reproductive and urinary tracts
- ALL PASSAGEWAY TO THE OUTSIDE WORLD
What are glands?
- Structures that produce fluid secretions
* either attached to or derived from epithelia
What is cellularity of the epithelia?
- Cells bound closely together by interconnections known as cell junction.
- in other tissue type, the cells are often widely separated by extracellular material
What is Polarity of the Epithelia?
- epithelium has an expose surface called APICAL and an attached one named BASAL.
- polarity refers to their difference in membrane structure & function
What is the attachment of the epithelia?
•the bounding of the base of the epithelia to a thin Basement Membrane or Basal Lamina (produced by the basal surface)
What is Avascularity of the Epithelia?
- lacks blood vessels
* Epithelial cells obtain nutrients by diffusion or absorption either the exposed or attached epithelial surface
What is regeneration of the epithelia?
- the exposed layer of the epithelia is constantly being replaced by stem cell division.
- this can be found in other tissues, but at a much slower rate
How many and what essential functions does epithelial perform?
•4
- Provide Physical Protection
- Control permeability
- Provide sensation
- Produce specialized Secretion
What does Celia in an epithelia m?
- moves substances in or out of the exposed surfaces
* example: mucus from lungs to throat to be expelled
What factors maintain the integrity of epithelia?
- Intercellular connections
- Attachment to the basement membrane
- Epithelial maintenance and repair
What is the transmembrane protein that interconnects areas of opposing plasma membranes?
•Cell Adhesive Molecules (CAMs)
What are the 3 most common type of cell junctions?
- Right junctions
- Gap junctions
- Desmosomes
What is lumen?
•A central space w/in a duct or other internal passageway
What are the types of desmosomes?
- Spot desmosomes- small discs connected to bands of intermediate filament (stabilize shape of cell)
- Hemidesmosomes- attaches a cell to extracellular filaments in basement membrane (stabilizes the position of the epithelial cell)
5 important characteristics of epithelia?
- Cellularity
- Polarity
- Attachment
- Avascularity
- Regeneration
How is epithelia classified?
1. By number of layers •simple •stratified 2. By cell shape •squamous •cuboidal •columnar