Animal tissues

AnimalTissues11 Any distinct type of material animal cells are made of, which consists specialized cells and cellular products, which show inflammation reaction to any infection or injury are known as tissues. Inanimal organs are made up of four basictypes oftissues epithelial tissue, connective tissue, muscle tissueand nerve tissue. These tissues have distinctive features and specific functions which combine to form functioning organs.

A tissue is composed of cells that function together in a specialized activity.

2Introduction2 There are four types of tissues found in an animal.

1. Epithelial tissue

2. Connective tissue

3. Muscle tissue

4. Nervous tissue3

1. Epithelial tissue

Forming tight covering and protecting layers below

2. Connective tissue

Holding other tissues together and are surrounded by lots of nonliving material.

4

3. Muscle tissue

Shortening and lengthening to move other tissues.

4. Nervous tissue

Allowing rapid flow of ions in and out to conduct signals

Nucleus ofschwann cell

Layer of myelin AxonNode of ranvierTerminal knobMyelin sheath AxonCell bodyNucleusDendrites5 1.Epithelial tissuesTwo types of epithelial tissues

1. Covering and lining epithelium ( outer layer of the skin and some organs)

2. Glandular epithelium ( constitute the secreting portion of glands)

6There are three types of cells in epithelial tissues

Squamous thin flat cellsForm the lining of cavities such as the mouth, blood vessels, heart and lungs and make up the outer layers of the skin

Epithelial tissues78Cuboidal cells are roughly squareEach cell has a spherical nucleus in the centerFound in glands and in the lining of the kidney tubules

3.Columnar - elongated cells. Nuclei are elongated and are usually located near the base of the cellsColumnar epithelium forms the lining of the stomach and intestines Some columnar cells are specialized for sensory reception such as in the nose, ears and the taste buds of the tongue

Three types of cell layers exist in epithelium tissues Epithelial tissues9CELL LAYERS10Simple epithelium made up of only one cell layerStratified epithelium has more than a single layer of cells

Pseudostratified epithelium madeupofcellsthatreachthebasementmembraneandappeartobestratifiedbecausetheirnucleiareatdifferentlevels.

Glands are made up of single or a mass of epithelial cells.

Two types of glands

1. Exocrine - Secrete their products in to ducts Eg . Salivary glands and mammary glands

2. Endocrine - Secrete their products into blood stream Eg. Pancreas

11Glandular epitheliumFunctions of epithelial tissues

Provides physical protection

Controls permeability

Detects sensations (sight, smell , taste, equilibrium)

Secretion of hormones into the blood vascular system, and/or the secretion of sweat, mucus, enzymes, and other products that are delivered by ducts12 2. Connective tissue

Most abundant and most widely distributed tissue in the body.

These tissues provide support for organs and the body as a whole, protect and insulate internal organs and compartmentalize structures such as skeletal muscles, nerves.

13 Connective tissue is made up of cells, ground substances and fibers. Ground substances together with fibers make matrix.14Connective tissue

15Connective tissueThere are 3 main types of connective tissueLoose Connective TissueFibrous Connective TissueSpecialized Connective TissuesAdipose Tissue (Fat)CartilageBoneBlood16Loose Connective Tissue (LCT)Fibroblasts are separated by a collagen fiber-containing matrixCollagen provides elasticity and flexibilityOccurs beneath epithelium in skin and many internal organsForms a protective layer over muscle, nerves and blood vessels17Fibrous Connective Tissue (FCT)Consists of many collagen fibers closely packed togetherOccurs in tendons, connecting muscle to boneMake up ligaments, connecting bone-to-bone at a joint

18AdiposeAnother name for fatInsulates the body and provides paddingCells sometimes referred to as ghost cells

19CartilageSoftStructural proteins deposited in the matrix between cellsForms embryonic skeletonsOccurs in mature human adults in ears, joints and tip of noseBlood tissue Blood transports nutrients and oxygen to cells and removes carbon dioxide and other wastesBlood cells are separated by plasmaTypes red blood cells, white blood cells, platelets

20Bone tissueCells are called osteocytes HardCalcium salts deposited in matrixProteins provide elasticity while minerals provide strengthDense bone has osteocytes located in lacunae (Haversian canals)Spongy bone occurs at the end of bones and absorb stress

(two types; compact and spongy) compact with osteons spongy - no osteons

2122Muscle TissueFacilitates movement by contraction of individual muscle cells referred to as muscle fibersFound only in members of the animal kingdomThree types:Skeletal (Striated)SmoothCardiacThese cells have main properties

Excitability ( ability to respond to stimuli)

Contractibility (ability to contract)

Extensibility (ability to be stretched without tearing)

Elasticity (ability to return to its normal shape) 23 Muscle tissue is classified into three types (Cardiac, Skeletal and Smooth)

24Muscular Tissue25Skeletal MuscleFunction in conjunction with the skeletal system in voluntary muscle movementStriated with alternating bands at right angles to the long axis of the cellThe bands are areas of actin and myosin depositionStriated, voluntary, and multinucleated

26Smooth MuscleLack bandingSpindle shaped cells that form massesFunction in involuntary movements and/or autonomic responses like breathing, secretion, etc.Make up structures in the digestive system, reproductive tract and blood vesselsnon-striated, involuntary, and single nucleus

27Cardiac MuscleStriatedLimited to the heartCells are forked, with nucleus near the centerCells are connected together by disksIntercalated disksstriated, involuntary, and single nucleus

28Nervous TissueImportant in the integration of stimulus and control of the response to that stimulusMade of nerve cells called neurons and glial cells (helper cells)Neurons transmit nerve messagesGlial cells are in direct contact with neurons and often surround them29The neuron is the functional unit of the nervous systemVariable in size and shapeHumans have about 100,000,000,000 (100 billion) neurons in their brain! Wow! Cells of nervous tissue have three principal parts

Dendrites

Cell body

Axon

Nucleus ofschwann cell

Layer of myelin AxonNode of ranvierTerminal knobMyelin sheath AxonCell bodyNucleusDendrites30Nervous Tissue Neuroglial cells that do not transmit impulses but instead support the activities of the neurons .

Schwann cells, a type in the peripheral nervous system only in mammals.

31Nervous Tissue

32SquamousCuboidalColumnarCilliatedGlandularAreolarAdiposeSkeletalFluidStriatedSmoothCardiacTendon

LigamentBone

CartilageBloodLymph