This is the link to the slides for the accompanying practical. Tissues http://www.gwc.maricopa.edu/class/bio201/histoprc/prac1q.htm This is the link to the slides for the accompanying practical.

Tissues Groups of cells to perform specialized structural and functional roles

4 major types of tissues: Epithelial Connective Muscle Nervous

Epithelial Tissue EpT

Epithelial Tissue Cover all body surfaces both interior and exterior, the major tissue of most organs

This tissue has two sides, one free side, and one attached by a basement membrane. Lacks blood vessels

Functions Secretion Absorption Excretion Sensory reception protection

Types Simple squamous Simple cuboidal Simple columnar Pseudostratified columnar Stratified squamous Transitional epithelium

1. Simple squamous Single layer of thin flattened cells. Cells are tightly packed Nuclei are broad and thin Located in areas of diffusion

2. Simple cuboidal Single layer of cubed cells Centrally located spherical nucleus Located in areas of secretion

3. Simple Columnar Single layer of elongated cells Nuclei located in a line near the basement membrane

Located in the linings of most organs Thick for protection Microvilli for increased surface area Goblet cells to produce mucus.

4. Pseudostratified Columnar Appear layered (Are NOT!) Nuclei are located at more than one level Goblet cells spread throughout

Cilia to keep mucus moving Located in tubes for transport (not vessels)

5. Stratified Squamous Epithelium Many layers of cells making a relatively thick tissue Cells reproduce in deep layers, older cells are pushed outward to die and be sloughed off.

Located in areas of exposure Contains the protein keratin in areas of outward exposure

6. Transitional Epithelium Specialized to deal with changing tension. When an organ is contracted the cells appear layered Lining may stretch to 1 cell thick.

Connective Tissue CT

Connective Tissue The most abundant tissue type by weight. Tissue varies in consistency from liquid semi-solid solid.

Well nourished by its own blood supply

Functions Provides support Serves as framework Fills spaces Stores fat Produces blood cells

6. Provides protection against infection 7. Helps repair tissue damage

Each CT is made up of cells and fibers.

Cell Types Resident cells: present in stable numbers Wandering cells: appear temporarily in injured tissues Mast cells: large, widely distributed, release heparin and histamine.

Fiber Types Collagenous: relatively thick, flexible but not very elastic, withstands a pulling force. (tendon) Elastic: not as strong but very elastic (vocal) Reticular: very thin, highly branched, form delicate supporting networks.

CT types Loose CT (areolar): binds skin to underlying organs fills spaces between muscle contains numerous blood vessels Layered fibers separated by a gel-like substance

2. Adipose (fat): Store fats in droplets Found beneath the skin, between muscles, and around organs Used for protection and insulation

3. Fibrous CT: Poor blood supply Densely packed tissue Withstand strong pulling force

4. Cartilage: Rigid CT Chondrocytes develop in lacunae Covered in perichondrium Blood supplied by perichondrium

Cartilage types: Hyaline: delicate, trachea Elastic: flexible, ears Fibrocartilage: shock absorbing, intervertebral discs

5. Bone: Most rigid CT Due to mineral salts

6. Blood: Most fluid Function in transport and regulation Components: Plasma: fluid RBC: carry oxygen WBC: immune function Platelets: cellular particles

Muscle Tissue MT

Muscle Tissue Contractile fibers Skeletal Smooth Cardiac

Nervous Tissue NT

Nervous Tissue Highly conductive Brain, spinal cord, and peripheral nerves Neurons: individual nerve cells Neuroglial cells: support cells, connect neurons to blood vessels

Continue with ALL applications within the chapter.