BIOA02H3 Lecture Notes - Lecture 13: Free Surface, Simple Columnar Epithelium, Nephron
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BIOA02H3 Full Course Notes
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Document Summary
Specialized cells tissues organs organ systems organisms. Tissues: a group of cells w/ same structure & function, working as a unit to carry out 1 or more activities. Organ: an assembly of tissues integrated into a structure that carries out a specific function. Organ systems: a group of organs that carry out related steps in a major physiological process. Epithelial tissue forms protective, secretory & absorptive coverings & linings of body structures. Properties of cells in tissues determine the tissues" structures and functions. Tight junctions seal cells into a leak-proof layer. Gap junctions allow cell to cell communication btwn. cytoplasm of adj. cells in same tissue. Have a polarity 2 parts w/ diff functions (apical and basal) Found in blood vessel walls; air sacs of lungs. Found in skin & other surfaces subject to abrasion, such as mouth, esophagus & vagina. Acts as protection against abrasion; typically not involved in secretion or absorption.
