The Tissue Level of Organization and It's Types Flashcards

Tissues are a group of cells found together. There are four different types of tissues, and each of them has different roles and functions. The flashcards bellow compromises of different kinds of tissue levels of organizations, and their definitions take a glance at these flashcards and learn more.

88 cards   |   Total Attempts: 182
  

Cards In This Set

Front Back
Four types of tissues
1. Epithelial tissue - covers exposed surfaces, lines internal passageways and chambers and forms glands. 2. Connective tissue - fills internal spaces, provides srtuctural support for other tissues, transports materials and stores energy reserves. 3. Muscle tissue - spezialized for contraction 4. Neural tisse - carries information in terms of electrical impulses.
Epithelial tissue
Consists of Epithelia - layers of cells that cover internal or external surfaces. Glands - structures that produce fluid secretions; either attached to or derived from epithelia.
Characteristics of epithelia
*Cellularity - cells very closely together by cell junctions. *Polarity - *Attachment - epithelia is attached to basal lamina. *Avascularity - lacks blood vessels. *Regeneration -
Functions of Epithelial Tissue
1. Provide physical protection - . 2. Control permeability - . 3. Provide sensations - . 4. Produce specialzed secretions - .
Microvilli
Covers epithelial cells that line internal passageways on their exposed surfaces. Abundant where absorbtion and secretion takes place, digestive and urinary tract.
Cilia
Moves substances over epithelial surface by synchronized beating - respiratory tract.
Factors that help maintain the physical integrity of an epithelium -3
1) Intracellular connections 2) attachment to the basal lamina 3) epithelial maintenance and repair
A basal lamina
Attaches epithelia to underlying connective tissues.
Three major types of cell junctions
1) Occluding junctions (tight) 2) Gap junctions 3) Macula adhernes (desmosomes)
Occluding junction (tight junction)
Prevents the diffuesion of fluids and solutes between cells.
Gap junction
Permits the free diffusion of ions and small molecules between two cells.
Macula adhernes (desmosomes)
Provides durable interconnections. Very strong and can resist stretching and twisting. Formed by two cells. Within each cell is a complex dense area, which is connected to the cytoskeleton - gives epithelium its strenght. Abundant in superficial layers of the skin. As a result skin is lost in sheets rather than cells. Two types: Spot desmosome and Hemidesmosome.
Spot desmosome
Kj
Hemidesmosomes
Attaches a cell to extracellular filaments in the basal lamina. This helps stabilze the position of the epithelial cell and anchors it to underlying tissues.
Epithelial maintenance and repair
Continual division of stem cells, also called germinative cells. Located near the basal lamina.