Tissue and Body Cavities -- EPITHELIAL HALF

3 Components Tissues have

Cells, Intercellular products, Fluid (interstital)

Four main types of Tissue

Epithelial, Connective, Muscle, Nervous

Epithelial Tissue Purpose

Covers and lines

Connective Tissue Purpose

Provides support

Muscle Tissue Purpose

Enables movement

Nervous Tissue Purpose

Controls work

Cytology Def.

Subspecialty of anatomy ;Structure and function of individual cells

Pathology Def.

Changes in gross anatomy, histology, or cytology in disease or injury

Necropsy Def..

gross and micro exams of tissues post mortem

Parenchyma

Functional portion of tissue, organ

Stroma

Support cells of parenchyma

Epithelial Tissue Functions

Protects, covers, lines, Filters biochemical substances, Absorbs nutrients, Provides sensory input, Manufactures secretions/excretions

Are epithelial cells polar or nonpolar?

Polar

What are the two surfaces of epithelial cells?

Apical surface, Basal surface

Are epithelial cells avascular or vascular?

Avascular

Basement membrane Def.

Meshwork of fibers that cement epithelial cells to underlying tissues

Cellular Attachments Def.

Lateral surfaces that fit together like a jigsaw puzzle

Three types of cellular junctions

Tight, Desmosome, Gap junction

Call Junction: Tight Def.

Adjacent plasma membranes are fused

Call Junction: Desmosome Def.

High tension areas; Intermediate filaments form tough bonds

Call Junction: Gap Junctions Def.

Linked by Tubular channel proteins (connexons) that connect adjacent cytoplasms

Three classifications of epithelial cells

Squamous, Columnar, Cuboidal

Simple Squamous Def.

Flattened, thin, delicate; Needs to be permeable

Simple Cuboidal Def.

Found in exocrine and endocrine tissues; Where secretion and absorption occur

Simple Columnar Epithelium

Tall narrow cells; Lines organs with absorptive/secretory functions

Stratified Epithelium Def.

Thicker and tougher; Subjected to friction and shearing forces

Transitional Epithelia Def.

In some organs that stretch; Leakproof

Ciliated Epithelium Def.

Single layer of columnar cells with cilia

Endocrine Glands Def.

No ducts or tubules; Secretions all over body; Secrete hormones

Exocrine Glands Def.

Ducts deliver secretions directly to tissues; Act locally, do not enter bloodstream

Unicellular Exocrine Glands

Individual secretory cells

Multicellular Exocrine Glands

Secretory unit + duct; Surrounded by connective tissue; Controlled by hormones, nervous system

Tubular Glands shape

Tubes

Acinar Glands shape

Acini

Alveolar Glands shape

Alveoli

Simplest form of Multicellular Gland is…

Secretory Epithelia Sheath

Secretory Epithelia Sheath Def.

A surface epithelium consisting entirely of secretory cells

Three types of mechanisms for Secretory Cells…

Merocrine, Apocrine, Halocrine

Merocrine Def.

Secretion corresponds to the process of exocytosis

Apocrine Def.

Part of the apical cytoplasm of the cells is lost together with the secretory product

Halocrine Def.

Secretion designates the breakdown and discharge of the entire secretory cell/cell death