UNIT 2: ANIMAL TISSUE

UNIT 4: ANIMAL TISSUE

Campbell and Reece, 2010. Chapter 40 p. 856 860

WHERE DO TISSUES FIT IN THE LIVING ORGANISM?Life begins as a single cell called a zygote after fertilizationThis cell differentiates into a variety of tissues. (Group of cells with the same function) A group of tissues with the same function forms an organ.Group of organs Organ systemGroup of organ systems - Organism

WHAT IS TISSUE?

SPECIALIZED CELL of the same type that perform a common function in the body.

MAJOR TYPES OF ANIMAL TISSUEEPITHELIAL TISSUE: Covers or lines body cavity and forms glands.CONNECTIVE TISSUE: Binds different organs together and support the body.MUSCLE TISSUE: MovementNERVOUS TISSUE: Senses and transmits impulses

SQUAMOUS EPITHELIAL TISSUESTRUCTURESingle layer thin, large, flattened cellsCells have irregular shape and are closely packed in mosaic form.Cells are attached to a basement membrane.FUNCTIONS Diffusion of gasses can occur easily over surface.Supply friction free surface for blood flow.Protects and supports underlying tissue

SQUAMOUS EPITELIAL TISSUEWHERE?Lining of lungs and blood vesselsIn mouth and esophagus.

CUBOIDAL EPITHELIAL TISSUESTRUCTUTESquare cells, closely packed in a single layer.Cells attached to a basement membrane.FUNCTIONAbsorbs molecules

CUBOIDAL EPITHELIAL CELLSWHERE?Lining of kidney tubulesLining various glands.

COLUMNAR EPITHELIAL TISSUESTRUCTURETall elongated, column-shaped cells.Nucleus near the base of the cell.Cells are attached to a basement membrane.FUNCTIONSPlays a role in absorption of nutrients.Protects and supports underlying tissues.COLUMNAR EPITHELIAL TISSUEWHERE?Lining of small intestine, stomach and oviducts

CILLIATED CULUMNAR EPITHELIAL TISSUESTRUCTUREComprises of columnar cells with cilia at their free edgesFUNCTIONSSweeps impurities towards throat Improves movement of substance through the ducts.

CILLIATED COLUMNAR EPITHELIAL TISSUEWHERE?Lining of trachea and nostrils, bronchi and sperm ducts)

GLANDULAR COLUMNAR EPITHELIAL TISSUESTRUCTUREConsist of cuboidal and columnar epithelial cells.Unicellular glandular cells with goblet cells scattered among non-glandular cells.FUNCTIONSProduce mucus which serves to lubricate the intestine and make movement of food easier.Keep respiratory passage moist.Secrete enzymes, hormones, sweat, wax and saliva.

GLANDULAR COLUMNAR EPITHELIAL TISSUEWHERE? In small intestine and respirative passages. Occur in salivary glands, thyroid gland and sebaceous glands in the skin.

16CONNECTIVE TISSUE FIBROUS CONNECTIVE TISSUE SUPPORTIVE CONNECTIVE TISSUE FLUID CONNECTIVE TISSUEFIBROUS CONNESTIVE TISSUE LOOSE AREOLAR FIBROUS CONNECTIVE TISSUEDENSE WHITE FIBROUS CONNECTIVE TISSUEDENSE YELLOW FIBROUS CONNECTIVE TISSUEADIPOSE TISSUELOOSE AREOLAR FIBROUS CONNECTIVE TISSUEOccurs beneath the skin and most epithelial layers connecting organs together.Filling the spaces between organs and muscles, around muscles and blood vessels

DESCRIPTION OF AREOLAR-Loosely arranged tissueIn jelly-like matrix there are 4 types of living cells and two types of non-living cells.Macrophages Mast cells Fat cells Fibroblasts Collagen fibres Elastic fibres

FUNCTIONS OF AREOLAR-Areolar tissue binds organs or organ components together and supports structures.Allows for movement between structures.The matrix allows for diffusion of substances like gases, nutrients, hormones and wastes to and from the blood.

Fibroblasts secrete collagen and produce elastic fibres.Macrophages Engulf foreign particles by means of phagocytosis to defend the body against infection.Mast cells They secrete the matrix, release histamine during inflammation, produce heparin (anticoagulant).Fat cells Synthesis and storage of fats.Collagen fibres strengthen the tissue.Elastic fibres Allows for expansion and contraction.

MACROPHAGES, PLASMA CELLS MAST CELLS AND ELASTIC FIBRES

FIBROBLASTS

DENDE WHITE FIBROUS CONNECTIVE TISSUEIn dermis of skin, tendons

FUNCTIONS:Attach muscle to bones

DESCRIPTION OF DENSE WHITE-Consist of mainly white collagen non-elastic fibres.The collagen fibres are non-elastic, densely packed, arranged in parallel bundles, and has a shiny appearance.Fibroblasts are elongated cells and occur parallel in rows.Minimum amount of matrix.YELLOW FIBROUS CONNECTIVE TISSUEIn ligaments

FUNCTIONS:Attach bone to boneHold bones of a joint in place.Restrict movement of bones and prevent dislocation during normal movement.

DESCRIPTION OF DENSE YELLOW-Consist of white collagen fibres and a network of yellow elastic fibres.Ligaments are strong and flexible.

ADDIPOSE TISSUEFound beneath the skin, around heart and other organs.FUNCTION:InsulationStores fat.DESCRIPTION:Large round cells filled with fat or oil.

COLLAGEN FIBRES AND ADIPOSE CELLSSUPPORTIVE FIBROUS CONNECTIVE TISSUE HYALINE CARTILAGEWHITE FIBROUS CARTILAGEYELLOW ELASTIC CARTILAGE BONEHYALINE CARTILAGEOccurs at the ends of bones in movable joints. Parts of the larynx.In the walls of the trachea and bronchi. In between the ribs and the sternum.On the tip of the nose

DESCRIPTIONContains fine collagen fibres.White translucent matrix.Cartilage tissue is surrounded by a fibrous capsule called the perichondrium with blood vessels for nutrition.It consists of living cells called chondrocytes.They occur in small fluid-filled spaces called lacunae. In the lacunae the cells are arranged singular or in groups.

FUNCTIONSChondrocytes produce a rubber matrix called chondrin.Reduce friction at jointsAttach bones firmly to other bones.Keeps tubes open (C-shaped in trachea).Forms permanent structures (nose).Longitudinal growth of long bones.

FIBROCARTILAGEOccurs as disks between the vertebrae.Surrounds the edges of the sockets of ball-and-socket joints.Between the pubic bones in front of the pelvic girdle.

FUNCTIONSIt serves as shock absorbers between adjacent vertebrae.It deepens sockets to make dislocation less easy.

DESCRIPTIONContain a large number of collagen fibres.White translucent matrix.Cartilage tissue is surrounded by a fibrous capsule called the perichondrium with blood vessels for nutrition.It consists of living cells called chondrocytes.They occur in small fluid-filled spaces called lacunae. In the lacunae the cells are arranged singular or in groups.

ELASTIC CARTILAGEIn the ear lobeAt the tip of the noseIn the epiglottis.Septum of nose

FUNCTIONSIt maintains the shape and flexibility of the ear lobe and tip of the nose.It strengthens and supports the ear, nose and epiglottis.

DESCRIPTIONContain collagen fibres and a large network of elastic fibres.Translucent matrix.Cartilage tissue is surrounded by a fibrous capsule called the perichondrium with blood vessels for nutrition.It consists of living cells called chondrocytes.They occur in small fluid-filled spaces called lacunae. In the lacunae the cells are arranged singular or in groups.COMPACT BONEOccur in the bones of the skeleton

FUNCTIONSSupport ProtectionLocomotionRed blood corpuscles and white blood cells are produced in the red bone marrow.

DESCRIPTIONThe matrix of compact bone consists of collagen fibres together with calcium, phosphorus and magnesium.These components are arranged in circles called lamellae, around the Haversian canal, containing artery, vein and nerve.Contain bone cells called osteocytes

FLUID CONNECTIVE TISSUEBLOODBLOOD PLASMAERYTHROCYTESLEUCOCYTESBLOOD PLATELETS

BLOODPLASMAWHERE?Matrix in which the blood cells are found.FUNCTIONS:Transport various formed elements to body parts.Dispersion medium.Transports digested food.Transports cellular waste.Transports hormones.Plays a role in regulation of body temperature.Transports antibodiesDESCRIPTIONStraw color fluid consisting mainly of water with many substances in solution like nutrients, organic waste, inorganic salts and ions, plasma protein, dissolved gases, hormones, enzymes and antibodies.ERYTHROCYTES (RED BLOOD CELLS)FUNCTIONS:Transports oxygen in the blood from the lungs to all living cells.Transports some of the carbon dioxide from the body tissues the lungs.Play a role in the clotting of blood.Play a role in the regulating of pH of body fluids

DESCRIPTIONSmall round biconcave disks filled with cytoplasm, but without a nucleus.Contain the red pigment hemoglobin. Hemoglobin contains 4 units, each with the protein globin and a complex iron-containing, structure called heme. The iron form a loose association with oxygen and in this way red blood cells transport oxygen and readily give it up to tissues.LEUCOCYTES(WHITE BLOOD CELLS)FUNCTIONS:Engulf infections by means of phagocytosis.Produce antibodies.Defense or immunity of body

DESCRIPTIONLarger cells with nuclei.Without staining they appear transparent.Irregular is shape. there are 5 types of leucocytes based on differences in size and nuclear shape:NeutrophilsEosinophilsBasophilsMonocytes.Lymphocytes.

BLOOD PLATELETSDESCRIPTION:Fragments of giant cells, present only in bone marrow.They are small discs without nuclei and bounded by a typical cell membrane.A characteristic feature of platelets is their tendency to stick to foreign surfaces and to each other to form clumps.FUNCTIONS;When blood vessels are damaged, platelets form a plug that seals the vessel, and injured tissues release molecules that help the clotting of blood.

MUSCLE TISSUESMOOTH MUSCLE CARDIAC MUSCLE SKELETAL MUSCLE -

SMOOTH MUSCLEFound wide spread in body.Found in the walls of bloodvessels, digestive tract, respiratory ducts, urinary ducts and reproductive ducts.In iris of eye and form small muscles attach to hair follicles

FUNCTIONS OF SMOOTH -Control slow involuntary movements of organs performing important life processes e.g. Contraction of stomach wall during peristalsis.Responsible for the movement of substances in internal passages e.g. Blood in blood vessels.

DESCRIPTION OF SMOOTH -Every smooth muscle fibre is an elongated, thin cell with a thick central part and pointed ends.Every cell has a big nucleus centrally situated.This muscle is never connected to bone.Can contract for long with out causing a spasm e.g. Uterus wall during birth.

CARDIAC MUSCLE TISSUEFound only in the heart.

DESCRIPTION OF CARDIAC -Contain many mitochondria, glucose and blood supply.Consist of branched cells with one or two central nuclei.Cells are rectangular and connected with muscle bridges.The ends of 2 cells are attached by intercalated disks.

FUNCTION OF CARDIAC MUSCLEIt causes the rythmic beating of the heart so that blood can flow through the whole body.

SKELETAL MUSCLE TISSUE

SKELETAL MUSCLE TISSUE

NERVE TISSUE

NERVOUS TISSUENervous tissue is composed of highly specialized nerve cells called neurons and supporting cells or neuroglia. The neurons, which are the basic units of communication, react to stimuli and transmit the impulses (information) form one region of the body to another.Neurons extend throughout the body and do not act alone.

STRUCTURE OF A NEURONNeurons are usually long, large and complex in shape. It consists of a cell body and several cytoplasmic processes.Processes that transmit impulses to the cell body are dendrites and usually are multiple.The single process that transmits impulses away forms the cell body in the axon.The cell body contains a nucleus, neurofibrills, Nissl granules, neuroplasma.

Three types of neurons according to structure:

Unipolar neurons Bipolar neurons

Multipolar neurons

Three types of neurons because of function:Sensory neuron Motor neuron Inter-