Chapter 5

Tissues

Atoms Macromolecules Cells Tissues

The study of tissues is called Histology

Epithelial Cells

Nerve Cells

Connective & Muscle Cells

There are FOUR major types of tissues in the body.

A characteristic of epithelial tissues is one side is exposed to the outside of the body or to an internal space. The other side is anchored to connective tissue by a nonliving layer basement membrane

Epithelial Tissue forms a covering

Simple Squamous Epithelium

Found in lungs, capillaries & blood vessels, line body cavities, very thin and delicate

Cuboidal Epithelium

Found in the ovaries, kidneys, salivary glands, thyroid gland, pancreas and liver

Lining tubes or ducts in these structures

Columnar Epithelial

Found in the stomach, small intestine, large intestine. Some have cilia and are found in the female reproductive system.

Goblets cells produce mucus that protects the cells

Pseudostratified Columnar Epithelium

These line the tubes of the respiratory system to remove dust and micro-organisms

Goblet Cells produce mucus to trap the particles

Stratified Squamous Epithelium

Skin, mouth, esophagus

Stratified Cuboidal Epithelium

Line the ducts of the mammary glands, sweat glands, salivary glands and pancreas. Also found in ovaries and testes

Stratified Columnar Epithelium

Found in the pharynx, urethra, ductus deferens

Transitional Epithelium

Found in the urinary bladder, ureters and urethra

Can stretch as the bladder fills

Exocrine Glands – Deliver secretions by way of a duct or tube to the inside or outside of the body

Release contents with no cellular damage to

gland

Release content with some cell

damage

Release entire cells that

breakdown to release contents

Table 05.04

Most common structural protein is Collagen.

Called Yellow Connective Tissue

The most common structural protein is Collagen

Fibroblast – most common connective tissue cells

Their fibers strengthen tissues

Scavenger Cell – another very common connective tissue cell

This is a scavenger cell

Mast Cell

Found near blood vessels produce

heparin to prevent clots

Produce histamines to

promote inflammation and

cause allergic response

Areolar Tissue

Makes thin membranes throughout the body surrounding muscle groups and connects skin to underlying muscles

Areolar means “open spaces” in latin

Adipose Tissue

Contains are amounts of fat, layer under skin is for protection and insulation

This is the most common loose connective tissue in the body

Reticular Tissue

Thin collagenous fibers provide a framework to internal organs such as the liver and spleen

Dense Connective Tissue

This tissue makes up tendons, ligaments and cartilage. It has a poor blood supply so is very slow to repair.

Cartilage – Three Types : Hyaline Cartilage, Elastic Cartilage and Fibrocartilage

Hyaline – Most common type, found at the end of bones, nose, respiratory system

Elastic Cartilage

Found in the external ear and larynx

Fibrocartilage

Very tough cartilage found in the intervertebral discs, knees and pelvis

Bone

Blood – it is a liquid connective tissue

The Plasma is what holds the blood together

Skeletal or Striated Muscle

Also called Voluntary Muscle – It does what you want it to do

Smooth Muscle

Also called Involuntary Muscle – It takes care of itself

Cardiac Muscle

This is Involuntary Muscle

Neuron or Nerve Cell

Neuroglial or glial cell are crucial to the functioning of the neurons, they support neurons by supplying nutrients and cell to cell communications.

There are three types of Neurons: Motor, Sensory and Associative