Chapter 5: Tissue

Types of Tissues A tissue is composed of specialized cells that perform a function in the body. The human body has four major types of tissues:

The 4 types are: 1.Epithelial 2.Connective 3.Muscle 4.Nervous

Some Cancers that occur in tissue are: Carcinomas – cancers of epithelial tissue Sarcomas – cancers of connective tissue Leukemia – cancer of blood Lymphomas – cancers of lymphatic tissue

1. Epithelial Tissue Characteristics of epithelial tissue: Epithelial tissue is made of highly packed cells that line the body surface and inner body cavities. Epithelial tissue functions in protection, secretion, absorption, excretion, and filtration.

Obj. #1: Describe the types of Epithelial Tissue 1.Simple Squamous epithelium a single layer of of flattened cells is found lining the lungs and blood vessels. Allows substances to pass into and out of tissue…when oxygen enters blood stream

Simple squamous epithelium These flatten cells allow diffusion into and out of the cell.

2. Cuboidal epithelium contains cube-shaped cells is found lining the kidney tubules and glands functions to store secretions

Simple Cuboidal Ttissue

3. Simple Columnar epithelium has elongated cells with nuclei at the bottom of cells is found in the digestive tract. secretes digestive fluid absorbs nutrients cells have microvilli on ends to increase absoption has goblet cells that make mucus

Simple Columnar Epithelial

4.Pseudostratified Columnar epithelial- Long cells with cilia on end Lines respiratory tract and reproductive tract Promotes movement of mucus in repiratory tract Promotes movement of egg in oviducts

Pseudostratified ciliated columnar epithelium

5.Stratified Squamous Found in outer skin and lines the mouth Occurs in layers- stacks of flatten cells Oldest layer is on top…youngest on bottom Protects body from invasion Outer layer sloughs off as cells die

Stratified Squamous Epithelium Topmost layer is dead cells They flatten out and form a protective layer Skin

6.Transitional epithelial tissue Stretches Found in bladder

Transitional Epithelial

Obj. #2 Describe Connective Tissue Characteristics: binds organs together, provides support and protection, fills spaces, produces blood cells, and stores fat. matrix material is the material that fills the cell. It is a semifluid or solid. Different types of fibers float in matrix

Types of Connective Tissue. 1. Loose fibrous-supports epithelium and many internal organs. Wrinkles form when loose fibrous tissue ages. Sun exposure cause fibers in loose to break much like a rubber band breaks.. this leads to wrinkles forming

Loose fibrous connective tissue

2. Dense fibrous-is found in tendons and ligaments. Very tightly packed cells Has very little blood supply..so when a person injures a ligament or tendon…it will take a long time to heal

Dense Connective Tissue

3.Adipose tissue is found beneath the skin and around certain internal organs. Functions: Cushions Insulates Stores energy-cells look empty…but contain fat droplets

Adipose (fat) Connective Tissue Lipid (fat) droplet nucleus collagen fibers

4. Cartilage Cartilage found in outer ear, nose, and between bones. Function: Flexible Protects

Cartilage

Bone is the most rigid connective tissue with its matrix of calcium and other inorganic salts and protein fibers. Compact bone makes up the shafts of long bones and consists of ring-linke circels called osteons which contain blood vessels and nerves. 5. Bone

Compact bone

6. Blood Blood is a fluid connective tissue containing blood cells in liquid plasma. Blood has many functions: Keeps body chemistry within limits Transports nutrients and wastes to cells Distributes heat

Blood, a fluid tissue

Formed elements of blood

There are 3 types 1. Skeletal muscle, under voluntary control, is attached by tendons to bones and allows for movement. - have striations which are bands of fibers Obj. #3 Describe Muscle Tissue

Skeletal muscle

2. Smooth (visceral) muscle is involuntary and nonstriated. Long, tapered cells, Smooth muscle is found in walls of organs. Smooth muscle contracts more slowly than skeletal muscle but can remained contracted for a longer period.

Smooth muscle

3. Cardiac muscle is found only in the walls of the heart and functions to pump blood. Cardiac muscle has striations but is involuntary. Cardiac muscle fibers are branched and have a single nucleus.

Cardiac muscle

4. Nervous Tissue Nervous tissue found in the brain and spinal cord is made up of cells called neurons. Neurons have three parts: Dendrites – carry impulses to the neuron Cell body – houses nucleus Axon – carries impulse away from cell

Nerve Tissue Neuron process nucleus nucleolus Neuroglia

A neuron and some types of neuroglia