Connective Tissue

3 Components Specialized Cells Protein Fibers (outside the specialized cells) Fluid ground substance “semi-fluid matrix” Examples: bone, fat, and blood

Types of Connective Tissue Loose Connective Tissue (areolar) Structure-general The least specialized tissue in the body Few specialized cells made up mostly of ground substance Contains elastin- therefore it can distort and return to its original shape Also contains collagen fibers Function-general Found underneath the skin Forms a layer that separates skin from deeper structures. Cushions shocks- provides padding Surrounds and supports blood vessels and nerves Stores lipids Contains tiny capillaries therefore it’s a good route for diffusion (subcutaneous shots)

Loose Connective Tissue

Specialized Loose Connective Tissue Adipose Tissue- “fat” Structure Specialized cells called adipocytes plus a “matrix” of fluid and protein fibers Each adipocyte contains a fat vacuole with lipids stored in it Function Adipose tissues accounts for 15-30% of the normal adult weight. Its is an energy reserve Padding cushions shock Insulator Supports tissues and organs

Adipose Tissue

Specialized Loose Connective Tissue Reticular Tissue Structure - fibrous framework or “stroma” Function - supports the functional cells of organs Location - spleen, liver and lymph nodes

Reticular Connective Tissue

Dense Connective Tissue Is also called “collagenous tissue” or “fibrous connective tissue” Dominant protein fibers are collagen Specialized cells are called fibroblasts Ground substance is clear and colorless

Types Of Dense Connective Tissue Dense Regular Connective Tissue structure- collagen fibers are arranged parallel to each other and are tightly packed fibers are aligned with forces placed on tissues.

Dense Regular Connective Tissue Examples: i. Tendons- Structure: are similar to cords Have large number of fibroblasts between collagen fibers Function: connect skeletal muscle to bone Transfer pull of contracting muscle to bone

Tendons

Dense Regular Connective Tissue Aponeuroses and Muscle Fascia- Structure- sheets or ribbons somewhat like broad, flat tendons Function- attach, stabilize, enclose and separate muscles and other internal organs

Dense Regular Connective Tissue Elastic Tissue- Structure- here the elastin fibers outnumber the collagen fibers Specialized cells are still fibroblasts Function- cushions shocks to body Can stretch and rebound, expand and contract Walls of blood vessels and respiratory passages, stabilize position of spine.

Elastic Tissue Aorta

Dense Regular Connective Tissue Ligaments- Structure- resemble tendons Contain elastin and collagen fibers Function- can tolerate a small amount of stretching Connect bone to bone

Types of Dense Connective Tissue Dense Irregular Connective Tissue Structure- fibers form an interwoven meshwork that do not show a pattern Function- provides strength to resist forces applied to the body Gives skin its strength Prevents overexpansion of urinary bladder Surrounds organs such as the kidneys and spleen Encloses cavities of joints

Irregular Connective Tissue

Types of Connective Tissue Fluid Connective Tissue Structure- watery ground substance or fluid matrix called plasma Specialized cells called “formed elements” including: Red Blood cells- Erythrocytes White Blood cells- Leukocytes Platelets Functions- transports oxygen and carbon dioxide Protects against disease Closes wounds Transports nutrients to the cells of the body.

Types of Connective Tissue Supporting Connective Tissue Two Types: Cartilage: Structure: specialized cells called Chondrocytes fluid matrix is a firm gel may or may not contain collagen or elastin Types/ Funcitons: HYALINE cartilage: covers bony surfaces and acts as “pads” between bones. ELASTIC cartilage: connects the ribs, supports passageways, forms ears and nose. FIBROCARTILAGE: makes up “framework” for the body of embryonic humans

Hyaline Cartilage

Types of Connective Tissue Bone- Osseous Tissue Structure: specialized cells are called osteocytes. Matrix contains calcium phosphate and calcium carbonate Collagen fibers are predominant Function: is the framework for the body. Provides support; the spinal Column, ribs, arm, and leg bones Provides protection; the skull, spinal column and ribs

Osteocytes (Owl Eyes)