Exam 2 Flashcards
What are the four types of tissues
Epithelial Connective Muscle Nervous
Define tissue
A group of cells that are always similar in structure and perform a common function
What do tissues contain that surround the cells
Extracellular matrix
Define extracellular matrix
A network of proteins and other molecules that surrounds and support cells and tissues
What are the characteristics that can be distinguished intercellular junctions
Cell size, shape, the amount of extracellular matrix, the type of extracellular matrix, organization, and function
What is a tight junction
Close space between cells by fusing the cell membrane
What are desmosomes
Bind cells by forming spot welds between cell membranes
What are gap junctions
Form tubular channels between cells that allow exchange of substances
What are epithelial tissue functions
Protect, secrete, absorb and excrete
What are epithelial characteristic
Lacks blood vessels and cells readily divide and are tightly packed
What are the three components of epithlial tissue
Apical surface, basal surface, and basement membrane
What is apical surface
Exposed to the outside or exposed internally to an open space
What is a basal surface
Made of a thin extracellular layer
What is the basement membrane
Anchors epithelium to underlying connective tissues and is mostly composed of tightly packed collagen fibers
How can epithelial tissue be classified
Cell shape and Number of cells
