Types of tissues

Major Tissue Types: Muscle Tissue

Contracts and produces force

Major Tissue Types: Epithetal tissue

Protects surfaces, and facilitates gas and nutrient exchange

Major Tissue Types: Connective tissue

Supports and transports

Major Tissue Types: Nervous Tissue

Transmits information

Connective Tissue Components

• Consists of cells

• extracellular fibers

• and matrix

Connective Tissues Classifications

• Connective Tissue Proper

• Fluid connective tissue

• Supporting connective tissue

Connective Tissue Proper (Viscous matrix)

• Loose: Fibers create a loose, open framework (e.g., reticular, adipose, and areolar tissue).

• Dense: Fibers are densely packed (e.g., dense regular, elastic, and dense irregular tissue).

Fluid Connective Tissues (Watery matrix)

• Blood: contained in circulatory system

• Lymph: contained in lymphatic system

Supporting Connective Tissues (Dense matrix)

• Cartilage: Features a solid, rubbery matrix (includes hyaline, elastic, and fibrocartilage).

• Bone: Features a solid, crystalline matrix.

Areolar Tissue Locations (Loose connective tissue)

• Found within and deep to the dermis of the skin

• covered by epithelial lining of the digestive, respiratory, and urinary tracts

• between muscles; and around blood vessels, nerves, and joints

Areolar Tissue Functions (Loose connective tissue)

• Cushions organs

• provides support while permitting independent movement,

• contains phagocytic cells that defend against pathogens

Adipose Tissue Locations (Loose connective tissue)

• Located beneath the skin (especially at the sides, buttocks, and breasts), posterior to the eyeballs, and around the kidneys

Adipose Tissue Functions (Loose connective tissue)

• Provides padding, cushions shocks, insulates against heat loss, and stores energy

• Dominated by adipocytes (fat cells)

Reticular Tissue Locations (Loose connective tissue)

• found in the liver

• kidney

• spleen

• lymph nodes

• and bone marrow

Reticular Tissue Functions (Loose connective tissue)

• Provides a supportive framework for organs

Dense Regular Connective Tissue Locations (Dense connective tissues)

• Between skeletal muscles and skeleton (tendons and aponeuroses)

• between bones (ligaments)

• covering skeletal muscles, and in deep fasciae

Dense Regular Connective Tissue Function (Dense connective tissues)

• Provides firm attachment

• conducts pull of muscles

• reduces friction between muscles

• and stabilizes relative positions of bones

Elastic Tissue Locations (Dense Connective Tissues)

• Between vertebrae of the spinal column (ligamentum flavum and ligamentum nuchae)

• ligaments supporting the penis

• underlying transitional epithelia, and in the walls of blood vessels

Elastic Tissue Function (Dense Connective Tissues)

• Stabilizes positions of vertebrae and penis

• cushions shocks,

• allows expansion and recoil of organs

Dense Irregular Connective Tissue Locations (Dense connective tissue)

• Capsules of visceral organs

• dermis of skin, periostea and perichondria

• and nerve and muscle sheaths

Dense Irregular Connective Tissue Function (Dense connective tissue)

• Provides strength to resist forces applied from many directions

• helps prevent overexpansion of organs like the urinary bladder

Fluid Connective Tissue

Red blood cells, white blood cells, Platelets

Supporting Connective Tissue

Cartilage

Appositional Growth (Growth from the outside edge)

• Fibroblasts in the perichondrium's cellular layer divide and differentiate into chondrocytes.

• Newly formed chondrocytes begin secreting fresh cartilage matrix onto the surface.

• As the matrix thickens, new fibroblasts are continuously incorporated and replaced via divisions within the perichondrium.

Interstitial Growth (Expands Cartilage from Within)

• An existing chondrocyte inside a lacuna divides

• The two daughter cells secrete additional matrix while enclosed in the matrix.

• The accumulation of new matrix pushes the daughter cells apart, enlarging the cartilage structure from the inside out

Skeletal Muscle Tissue Locations:

• Cells are long, cylindrical, striated, and multinucleate

• Location: Combined with connective tissue and nervous tissue in skeletal muscles (such as arm or leg muscles)

Skeletal Muscle Tissue Function:

• Moves or stabilizes the skeleton

• guards entrances and exits to the digestive, respiratory, and urinary tracts

• generates heat

• protects internal organs

Cardiac Muscle Tissue Locations

• Cells are short, branched, and striated, usually with a single nucleus; interconnected by intercalated discs

• Location: Found only in the heart

Cardiac Muscle Tissue Functions

• Circulates blood and maintains hydrostatic blood pressure

Smooth Muscle Tissue Locations:

• Cells are short, spindle-shaped, nonstriated, and have a single central nucleus.

• Locations: Encircles blood vessels and is found in the walls of digestive, respiratory, urinary, and reproductive organs.

Smooth Muscle Tissue Functions:

• Moves food, urine, and reproductive secretions

• controls diameters of respiratory passageways

• regulates blood vessel diameter and tissue blood flow.

Neural Tissue Locations

• Cells have dendrites, body, and axon(s)

• Location: Combined with connective tissue, in brain, spinal cord, and throughout bod

Neural Tissue Function:

• Conduction of electrical impulse

Fasciae

• connective tissue framework of the body

• Superficial fasciae, deep fascia, subserous fascia

Superficial Fascia

• Subcutaneous Layer / Hypodermis

• Location: Found between the skin and underlying organs.

• Composition: Composed of areolar tissue and fat.

Deep Fascia

• Location: Bound to organ capsules, tendons, and ligaments.

• Composition: Composed of dense connective tissue.

• Function: Forms a strong, fibrous internal framework throughout the body

Subserous Fascia

• Location: Positioned between serous membranes (such as the parietal peritoneum) and deep fascia

• Composition: Composed of areolar tissue