A&P Review (Epithelial Tissue, Connective Tissue, Nervous Tissue, Muscle Tissue)

Hyaline Cartilage

- Most common type of cartilage - Composed of abundant collagen fibers and rubbery matrix - Locations: Larynx, entire fetal skeleton prior to birth - Functions as a more flexible skeletal element than bone

Loose Connective Tissue/ Areolar

- Most widely distributed connective tissue - soft, pliable tissue like "cobwebs" - Functions as a packing tissue - Contains all fiber types - Can soak up excess fluid

Elastic Cartilage

- Provides elasticity - Forms cushions - Highly compressible - Location is in external ear

Tissue Repair (Wound Healing)

- Regeneration: replaces the destroyed tissue by the same kind of cells - Fibrosis: repair by dense (fibrose) connective tissue (scar tissue) - Whether regeneration or fibrosis occurs depends on: the type of tissue damaged, or the severity of the injury

Regeneration of Surface Epithelium

- Scab detaches

Tissues that regenerate poorly

- Skeletal Muscle

Cardiac Muscle

- Under involuntary control - Found only in heart - Function: Pump blood - Characteristics: Striated, One nucleus per cell, Cells are attached to other cardiac muscle cells at intercalated disks

Skeletal Muscle

- Under voluntary control - Contracts to pull on bones and skin - Produces gross body movements or facial expressions - Characteristics of skeletal muscle cells: Striated, Multinucleate (More than nucleus), Long,cylinder cells

Smooth Tissues

-Under involuntary muscle -Found in walls of hallow organs such as stomach, uterus, and blood vessels -No visible striations -One nucleus per cell -Spindle-shaped cells

Simple Squamous

1 layer thick; flattened in shape; used in diffusion and filtration; found in air sacs in lungs, lining of blood vessels (exchange takes place in capillaries)

Connective Tissues

Connects body parts

Adipose Tissue

- Also known as fat tissue - Matrix is an areolar tissue in which fat globules predominate - Many cells contain large lipid deposits - Functions: insulates the body, protects organs, serves as a site of fuel storage

Blood (Vascular Tissue)

- Blood cells surrounded by fluid matrix called plasma - Fibers are visible during clotting - Functions as the transport vehicle for materials

Inflammation

- Capillaries become very permeable - Clotting proteins migrate into the area from the blood stream - a clot walls off the injured area

Tissues that are replaced largely with Scar Tissue

- Cardiac Muscle - Nervous Tissue within the brain and spinal cord

Bone (osseous tissue)

- Composed of bone cells in lacunae, hard matrix of calcium salts, large numbers of collagen fibers - Functions in protection and support

Nervous Tissue

- Composed of neurons and nerve support cells - Function is to send impulses to other areas of the body - Irritability - Conductivity

Reticular Connective Tissue

- Delicate network of interwoven fibers - Locations: forms stroma of lymphoid organs, lymph nodes, spleen, bone marrow

Tissues that repair easily

- Epithelial Tissue (skin and mucous membranes) - Fibrous Connective Tissues and bone

Developmental Aspects of Tissue

- Epithelial Tissue arises from all three primary germ layers - Muscle and Connective Tissue arise from mesoderm - Nervous Tissue arises from the ectoderm - With old age, there is a decrease in mass and viability in most tissues

Muscle Tissue

- Function: produces movement

Granulation Tissue Forms

- Growth of new capillaries - Rebuild collagen fibers

Fibrocartilage

- Highly compressible - Location: cushion like disks between vertebrae

Dense Connective Tissue

- Main matrix element is collagen fiber - Fibroblasts are cells that make fibers - Located in Tendons, Ligaments, and Dermis

Functions of Connective Tissue

Binds body tissues together, supports the body, and provides protection

Three Types of Fibers

Collagen, Elastic, Reticular

Endocrine Gland

Ductless since secretions diffuse into blood vessels; all secretions and hormones; secretions empty through ducts to the epithemic; include oil and sweat

Four Primary Types:

Epithelial tissue, connective tissue, muscular tissue, nervous tissue

Connective Tissue

Found everywhere in the body, includes the most abundant and widely distributed tissues

Glandular Epithelium

Glands with one or more cells responsible for secreting a particular product

Two Main Elements of Extracellular Matrix

Ground surface and fibers

Tissues

Groups of cells with similar structure and function

Pseudostratified Columnar

Looks stratified or looks like in layers, but really just odd shaped columnar cells with nuclei located in different parts of each cell. Found in the cells of the respiratory system.

Stratified Squamous

Layers of flattened cells; used in protection (covers areas of high abrasion); found in skin and upper digestive tract (mouth, esophagus)

Transitional Epithelium

Multiple layers of cells which appear cuboidal when not stretched, but squamous when stretched; found in the urinary organs

Extrocellular Matrix

Nonliving materials that surrounds living cells

Shape of cells:

Squamous, flattened, cuboidal, columnar

Fibers

Produced by the cells

Functions of tissues

Protection, absorption, filtration, secretion

Three Functions of Connective Tissues

Protection, support, binding together other body tissues

Simple Cuboidal

Single layer of cube shaped cells, usually with spherical nuclei. Covers ovaries and lines most of the kidney tubules and the ducts of certain glands.

Simple Columnar

Single layer of elongated, rectangular shaped cells. Secretion and absorption. Surface lining of stomach and intestines.

3 Types of Muscle Tissue

Skeletal, Cardiac, and Smooth

Neuroglia insulate

Support cells that protect and support neurons

Tissue Characteristics

Variations in the blood supply, some tissue types are well vascularized, some have poor blood supply (avascular)