Anatomy and Physiology Chapter 4

Cell Junctions

Contact points between the plasma membranes of tissue cells

Types of Cell junctions(5)

Tight Junctions, Adherens Junctions, Desmosomes, Herhidemosomes, and Gap Junctions

Gap Junction

Connexons connect neighboring cells to rapidly move energy or electricity to other cells. "Tunnels"

Tissue

Group of similar cells that predom specific functions

Types of tissues

Epithelial, Connective, Nervous, and muscular

Epithelium Tissue

Closely packed cells arranger in continuous sheets that form the outer covering of body, line body cavities and cover some internal organs. Avascular, and reproduce readily.

Apical Surface

Surfaces faces body surface- internally or externally.

Basal Surface

Opposite of Apical surface- adheres to basement membrane

Basement membrane

Basal lamina and reticular lamina

Vascular/Avascular

Not own nerve supply/Own nerve supply

Epithelial classification

Number of layers(Simple Vs. Stratified) and shape (Squamous Vs. Cuboidal Vs. Columnar)

Simple

Single layer of cells. Allow for diffusion, osmosis, secretion, excretion, absorption, filtration.

Stratified

For protection (skin), multiple layers on top of each other

Pseudostratified

Pseudo-false. Looks like multiple layers but all cells are touching basal surface.

Squamous

Thin and flat

Cuboidal

Cube shaped

Columnar

Cells in columns

Transitional

Cells appear one way, but change shape under different conditions

Glandular Epithelium

Cells lie in clusters deep to covering and lining epithelium, produce secretions. (Glands)

Endocrine Glands

Secretions(Hormones) enter the interstitial fluid and diffuses directly into blood stream with out flowing into a duct

Exocrine Glands

Cells produce a secretion into duct system that empties directly on surface of body or into a cavity (Sweat). Unicellular Vs. Multicellular. Simple Vs. Compound. Tubular Vs. Acinar Vs. tubuloacinar.

Tubular Vs Acinar Vs Tubuloacinar

Tube like Vs. Round Vs. Both

Merocrine

Most glands, excretes by vesicle- burst off and out of vesicle. Made in Endoplasmic Reticulum, move to golgi complex and then are released.

Apocrine

Separates off. Made in Endoplasmic Reticulum, move to golgi complex and then are released.

Holocrine

Excretes by bursting cell completely. Made in Endoplasmic Reticulum, move to golgi complex and then are released.

Connective Tissue

Most abundant in body, derived from mesenchyme, vascular, deep to epithelium

Functions of connective tissue

Protection, support, binding, insulation and transportation.

Composition of connective tissue

Cells Vs. Extracellular Matrix-> Ground substance Vs. Fibers

"___"Blast

Immature cell

"____"Cyte

Mature cell

Osteo

Bone

Chondro

Cartialge

Fibroblasts

Secrete substances of extra cellular matrix

defensive cells

macrophages, White blood cells, Mast cells, and plasma cells

Adipocytes

Store energy though triglycerides

Extracellular Matrix

Contain Ground substance and fibers

Ground substance

Supports cell and binds together- stores water

Fibers (Connective)

Strengthen and support matrix. Types- Collagen, elastic, and reticular

Collagen Fibers

Strength

Elastic fibers

Elasticity or stretch

Reticular fibers

Support

Ehlers Danlos Syndrome

Efficient in collagen- stretchy skin- no collagen between joints

Loose connective tissue (3)

Areolar, Reticular, Adipose->Adipocytes

Dense connective tissue(3)

Regular, irregular, Elastic

Regular connective tissue

all parallel

Irregular connective tissue

fibers in all different directions

Elastic connective tissue

Lungs and arteries

Cartilage

Avascular. Hyaline, elastic, fibrocartilage, bone, blood and lymph.

Hyaline cartilage

Most abundant. Flexible, support, reduces friction, absorbs shock. The weakest of cartilage.

Elastic Cartialge

Strong and elastic

Fibrocartilage

Strongest cartilage- very thick. Lacks perichondrium.

Muscle tissue(3)

Skeletal, Cardiac and Smooth

Skeletal muscle

Attaches to bone. Voluntary, striated, multinucleated.

Voluntary Vs. involuntary

You control the contraction Vs. Body does the contraction without your knowledge.

Multinucleated Vs. uninucleated

multiple nucleons Vs. One nucleus

Striated Vs. Smooth

Striped looking Vs. no striations

Cardiac tissue

Involuntary, striated, uninucleated. Heart

Smooth Tissue

Involuntary, no striations, uninucleated. Spindle shaped cells found in the walls of hollow structures.

Nerve Tissue

Tissue in the nervous system

cell types of nerve tissue(2)

Neurons, Neuroglia

Neurons

Nerve cells. Structure: Cell body, Axon, Dendrites

Neuroglia

Protective and supporting cells