Animal TissuePacket #52
Chapter #40
Introduction
Animals are predators and must be strong and agileMeans that tissue must possess characteristics of
capable of rapid movement and the cells that make up the tissue must be able to generate and transmit forces and change shape quickly
Animal Tissue II
Epithelial tissue
Connective Tissues
Muscular Tissue
Nervous Tissue
Connective tissueAnimal Tissue
Connective Tissue ICharacteristics
Extremely varied Tough and flexible
Tendons Dermis of the skin
Hard and dense Bone
Resilient and shock-absorbing Cartilage
Soft and transparent Jelly that fills interior
of the eye
Connective Tissue IIFunctions
Supporting function Cartilage Bone
Transport function Blood
Connective Tissue III
Bulk of this tissue is composed of extracellular matrix
Tensile strength provided by the fibrous protein collagen
Connective Tissue IVCollagen
There are 20 different variations of the protein
Chief proteins in bone, tendon and skin
Make up 25% of the total protein mass in a mammalMore than any other type of protein
Collagen is long, stiff and a triple stranded helical structureCollagen fibrils
10-300nm in diameter
Connective Tissue VCollagen
Homework Question How does procollagen
and the extracellular enzyme collagenase relate to the formation of collagen?
What is the result of a genetic disorder that results in the deficit of the enzyme collagenase?
What is the relationship between collagen, connective tissue and the movement of cells within the extra cellular matrix?
Muscular tissue
Muscular Tissue
All muscle cells can contract
There are three types Skeletal Cardiac Smooth
Muscular Tissue
Voluntary Skeletal Muscle The main type found in
mammals Composed of
Myofibrils Made up of
myofilaments Actin Myosin Responsible for
striped appearance
Nervous tissue
Nervous Tissue
Has highly developed properties of irritability and conductivity.
Composed of packed nerve cells known as neurons.
Epithelial tissue
Epithelial Tissue There are more than 200 visible
cell types in the body of a vertebrate
Acts as a protective barrier
May have complex biochemical functions and secrete specialized products Hormones Milk Tears
Absorb nutrients Lining of the gut
Detect signals Photoreceptors of the eye Auditory hair cells of the ear
Epithelial Tissue II
Epithelial tissue occurs in different forms based.
These forms are based on the type of epithelial cells.
Epithelial Tissue IIIStratified vs. Simple
Cells joined together, side to side, to form multicelluar sheets
Thick sheets (many cells) Stratified
Epidermis covering of the skin
One cell thick Simple
Lining of the gut
Epithelial Tissue IV
Compound (Stratified Epithelium)• Many layers of cells• Ones nearest to the
basement are normally flattened and dead
• Impregnated with keratin• Found where there is
considerable mechanical stress Epidermis of skin Esophagus Anal cavity Vagina
Epithelial Tissue V
Cells may be tall Columnar
Cells may be cubed shape Cuboidal
Cells may be “flat” Squamous
Epithelial Tissue VI
Columnar epithelium Tall narrow cells often
with cilia Used in transporting
mucus and other particles
Found in Nasal cavities Trachea Oviducts Ventricles of the brain
Epithelial Tissue VII
Squamous epithelium Called “pavement
epithelium” Flattened single layer of
thin nucleated cells Found where rapid
diffusion takes place Bowman’s capsule Alveoli Endothlium
Epithelial Tissue VIII
Since epithelial tissue are in the form of sheets, they have two sides (faces) Apical surface
Free and exposed to the air or to a watery fluid
Basal surface Rests on some other tissue
Usually connective tissue Basal lamina The basal lamina (often
confused with the basement membrane, and sometimes used inconsistently in the literature, see below) is a layer on which epithelium sits and which is secreted by the epithelial cells.
Review