Histology Sheet - Biology Tissues - 2005 PDF

‫‪Dr. mohamed-Elshebly‬‬ ‫البدايه بالكفاح والنهاية بالنجاح‬ ‫‪BIOLOGY‬‬ ‫‪TISSUES‬‬ ‫‪2005‬‬ ‫د‪.‬محمد‬ ‫الشبلي‬ ‫د‪.‬محمد الشبلي ‪ --- 0925121809‬اعداد طب ‪2005‬‬ ‫‪1‬‬ Dr. mohamed-Elshebly TISSUES  A...

‫‪Dr. mohamed-Elshebly‬‬ ‫البدايه بالكفاح والنهاية بالنجاح‬ ‫‪BIOLOGY‬‬ ‫‪TISSUES‬‬ ‫‪2005‬‬ ‫د‪.‬محمد‬ ‫الشبلي‬ ‫د‪.‬محمد الشبلي ‪ --- 0925121809‬اعداد طب ‪2005‬‬ ‫‪1‬‬ Dr. mohamed-Elshebly TISSUES  A tissue is a functional collection of cells & associated intercellular material that is specialized to carry out a specific role.  Groups of these tissues are assembled in various organizational & functional arrangements into organs, which carry out functions of the body.  About 200 different types of cells composing the human body are arranged & organized into four basic tissues. The four basic tissues is types are :  1 – Epithelium. 2 - Connective tissue.  3 – Muscle cells. 4 – Nervous tissue. 1 - EPITHILIUM TISSUE :  The outer surface of the body & the luminal surface of cavities lined by Epith.  Epithelia also line the glands. General features of epithelium tissue :  1 – All surfaces in the body are covered or lined by epith ( except joint cavities). Therefore serve as barrier membranes to separate the organism from external & internal environment.  2 – Epithelia rests on a basement membrane. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 2 Dr. mohamed-Elshebly  3 – Epithelia are generally Avascular , so nourishment of a epith occurs by diffusion from underlying connective tissue vasculature.  4 – Posses a remarkable capability for renewal & regeneration.  5 – The cells are compactly arranged on a thin basement membrane.  6 – Due to compact arrangement , intercellular spaces are usually absent.  7 – Epithelia are diverse in origin ; they are derived from all three primary germ layers (ectoderm , mesoderm & endoderm ).  8 – functions ( protection , lubrication , secretion , sensory , digestion , absorption , transduction & reproduction ) TYPES OF EPITHELIA :  Epithelia are divided into two main groups according to their structure & function into : 1 – Covering. 2 – Glandular. CLASSIFICATION OF EPITHEILIUM TISSUE :  1 –simple or Uni- layered : consist of only one layer of cells resting on basement membrane. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 3 Dr. mohamed-Elshebly  2 – stratified or Multi-layered : its composed of more than one cell. A )Simple epith classified according to the shape of the cells :  1 – Simple squamous epith : the cells are flattened ( their height very little as compared to their width ). Location : Glandular ducts of small caliber ,lining of pleural , Pericardial , peritoneal cavities ( mesothelium ) lining of cardiovascular & lymph hannels (endothelim ) , respiratory bronchioles and alveoli of lungs & Bowmans capsule of the kidney. FUNCTION : Limiting membrane , fluid transport & gaseus exchange. 2 – Simple cuboidal epith :  When the height & width of the cells are equal ( they look like squares ). 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 4 Dr. mohamed-Elshebly Location : Ducts of many glands , lining certain kidney tubules , rete tests & covering the free surface of the ovary. FUNCTION : secretion , absorption and protection. 3 – Simple columnar epith : when the height of the cells is greater than their width. Location : Digestive tract ( stomach , intestine , gall bladder ) , portion of female reproductive tract ( oviduct & uterus ). FUNCTION : Transportation & secretion. 4 – Pseudo stratified columnar epithelium : all cells rests on basement membrane (basal lamina ) but not all cells reach the surface  The nuclei not at the same levels. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 5 Dr. mohamed-Elshebly Location : Respiratory passages , Eustachian tube and portions of male and female urethra. FUNCTION : secretion & protection. B ) Stratified epith:  Two or more layers of cells.  Only the basal (lowermost ) layer of cells rest on the basement membrane.  According to the shape of the surface (outermost ) layer of cells , this epith divided into : 1 – Stratified squamous : ( keratinized and non keratinized )  Stratified Squamous keratinized : LOCATION : present in epidermis of skin. Function : protection.  Stratified squamous non-keratinized : LOCATION : lining mouth , epiglottis and vagina. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 6 Dr. mohamed-Elshebly Function : protection & secretion. 2 – Stratified cuboidal epith :  LOCATION : Lininig the ducts of sweat glands.  Function : Absorption and secretion. 3 – stratified columnar epithelium :  LOCATION : Present in conjunctiva of eye and portions of male urethra.  Function : secretion and absorption. 4- TRANSITIONAL EPITH : 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 7  Dr. mohamed-Elshebly  Was termed transitional because it was considered to be an intermediate between stratified squamous & stratified columnar.  The appearance of this epith varies depending on whether it is in its contracted or expanded state.  The shape of cells varies : Dome shaped cells ( relaxed ) flattened ( distended ). Location : lining urinary tract ( renal pelvis , ureters & urinary bladder ). function : Protection and distensible.. 2 -- CONNECTIVE TISSUE GENERAL FEATURES OF CONNECTIVE TISSUE : 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 8 Dr. mohamed-Elshebly 1 – Most connective tissues originate from mesoderm ( Middle layer ). 2 – It fills the interstitial spaces , hold structures together & support them. 3 –Responsible for providing form in the body & also provide matrix that connect & binds the cells & organs. 4 – Structurally , connective tissue is formed by three classes of component : A -- Cells. B-- fibers. C-- ground substance. 5 – It formed mainly by the extracellular matrix(ground substance ). ( Unlike other tissues ) Functions of connective tissues :  1 – Providing structural support.  2 – Serving as a medium for exchange.  3 – Aiding in the defense &protection.  4 – Forming a site for storage of fat.  Basic component of connective tissues : 1 – The ground substance : made up of A – Organic substance ( usually a protein ). B – Inorganic substance ( usually mineral or water ). 2 – Cells of connective tissue : Fibroblast :-  The principal cell of connective tissue.  This cell makes the fibers & found nearly all of the C.Ts. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 9 Dr. mohamed-Elshebly  Fibroblast are motile , able to carry out mitosis. Note :  The matrix in connective tissue gives the tissue its density.  When connective tissue has high concentration of cells or fibers , it has proportionally a less dense matrix. 3 -- Fibers of connective tissue : 1 – Collagen fibers :  Most numerous fibers.  Made up of collagen protein their function provide strength to the tissues & preventing it from separated from surrounding tissues. 2 – Elastic fibers :  Made up of elastin protein.  This fiber can stretch to one & half of its original length & return to its original size & shape.  This fibers provide flexibility to the tissues.  Highly resistance to pulling force. 3 – Reticular fibers :  Consist of collage type III.  Very thin  Form extensive networks in certain organs. Classification of connective tissue : 1 – Loose (areolar ) connective tissue :  Has some fibroblast & microphages. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 10 Dr. mohamed-Elshebly  Collagen fibers are wide & stain a light pink.  Elastic fibers are thin & stain dark blue to black.  The space between the elements filled by matrix.  This tissue has a loose consistency similar to cotton ball that has been pulled apart.  Its found around every blood vessels & help to keeps the vessel in place.  Also found around & between most body organs.  In summary areolar tissue is tough , yet flexible & comprise membranes. 2 – Fibrous ( Dense ) connective tissue :  Contain large amount of collagen fibers & few cells or matrix material.  The fibers can be arranged irregularly or regularly.  Irregularly arranged are found in areas of the body where stress occurs from all directions such as dermis of skin.  Regular fibrous is found in tendons ( which connect muscles to bones ) & ligaments ( which connect bone to bone. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 11 Dr. mohamed-Elshebly 3 – Adipose ( Fat ) tissue :  It does not have fibroblast or real matrix & only have few fibers.  Made up of cells called adipocyte or adipose cells.  Adipocyte that collect & store fat in form of triglycerides for energy metabolism.  Adipose tissue serve as insulation to help maintain body temperature , allowing animals to be endothermic.  They function as cushioning against damage to body organs.  Under a microscope , adipose tissue cells appear empty due to extraction of fat during the processing of material f  The thin lines in the image below are the cell membranes ,the nuclei are the small , black dots at the edges of the cells. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 12 Dr. mohamed-Elshebly 4 -- SPECILIZED C. T :  Like cartilage , blood and bone. A – Cartilage :  Contain cells called chondrocyte present in space called lacuna  The cartilage is Avascular ( no vessels ) , no nerves and no lymphatic vessels.  So the cells gets their nutrition from surrounding connective tissue by diffusion.  The extra cellular matrix is composed of proteoglycans and glycosaminoglycan associated with collagen and elastic fibers. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 13  Dr. mohamed-Elshebly Types of cartilages :  1 – Hyaline cartilage :  Bluish gray , semi translucent.  It’s the most common type in the body.  Covered by a layer called perichondrium.  Location : larynx , Nose , tracheal rings & act as a model before ossification. 2 – Elastic cartilage :  Its identical to hyaline cartilage and often associated with it.  Its also covered by periichondrium  Its matrix contain abundant elastic fibers.  Location : Pinna ( auricle ) of the ear & internal and external auditory tubes. 3 – Fibrocartilage :  Has no perichondrium.  Location : intervertebral disc & articular disc. B – BONE :  Is the primary structural framework for support and protection of vital organs ( like brain , spinal cord & Lung ).  Bone is covered on its external surface with periosteum except synovial articulation. CELLS OF BONE : 1 – Osteoprogenitor : the stem cell of the bone which differerentiate into osteoblast. 2 – Osteoblast : which responsible for secreting matrix of the bone that has become calcified. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 14 Dr. mohamed-Elshebly  3 – Osteocyte : when the osteoblast secrete matrix , they become osteocyte & occupy by lacuna.  4 – Osteoclast : which are multinucleated giant cells involved in resorption & remodeling of the bone. TYPES OF BONE : A - Gross observation : 1 – Compact bone : areas in the bone without cavities. 2 – Cancellous ( spongy ) bone : areas with numerous interconnecting cavities. B – Microscopic examination :  The Haversian system ( osteon ) : The bone shows collagen fibers arranged in lamellae that are parallel to each other or concentrically organized around a vascular canal.  The vascular canal ( Haversian canal ) contain blood vessels , nerves & loose tissue.  The Haversian canals communicate with each other through transverse or oblique Volkmanns canals. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 15  Dr. mohamed-Elshebly C -- Blood : Blood is specialized C.T.which composed composed of : 1 – Plasma. 2 – Cells : A – Red blood cells ( Erythrocyte ). B – White blood cells ( leukocyte ). C – Platelets ( Thrombocyte ). Plasma :  Translucent , yellowish , viscous obtained from blood after centrifugation.  Serum ( straw colored ) is plasma without clotting factors.  The major component is water 90% , 9 % proteins & 1% inorganic salts , ions , nitrogenous compounds , nutrients and respiratory gases.  The main plasma proteins are albumin, globulins , lipoproteins , prothrombin & fibrinogen. Cells of blood : Erythrocyte ( red blood cells ) :  The smallest & most numerous cells of blood.  Have no nuclei & responsible for transport of oxygen & carbon dioxide.  Each erythrocyte resemble a biconcave-shaped disk.  Have average lifespan 120 days , after that they destroyed by macrophage in the spleen , bone marrow and liver. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 16  Dr. mohamed-Elshebly LEUKOCYTE (White blood cells ) :  Migrate to the tissues , where they perform multiple function.  Have average life span days to years.  Leukocyte are classified according to the presence or absence of granules into : 1 – Granulocyte ( Neutrophils , basophils & eosinophils ) 2 – Agranulocyte ( monocyte & lymphocyte ) FUNCTION : Phagocyte , destroy bacteria , kill parasitic invaders & initiators of inflammatory process. Platelets ( Thrombocyte ) :  Non nucleated disk like cell fragments.  2 – 4 mm in diameter.  Life span : 7 – 11 days. FUNCTION : 1 – Promote blood clotting. 2 – Help repair gaps in the walls of blood vessels , preventing blood loss. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 17 Dr. mohamed-Elshebly LYMPH :  Its transudate from blood.  Contain the same proteins as in plasma , but in smaller amount.  The lymph contain some cells , mainly lymphocyte.  The lymph returned to circulation through a separate system of lymphatic vessels.  The fluid passing through lymphtic vessels is called lymph. Tissue Cells Fibers Location Loose\areolar Fibroblast, Few : collagen , Around blood macrophage, elastic , & vessels Some lymphocytes , reticular some neutrophils. Dense Fibroblast & Mostly collagen Irregular : skin ( fibrous ) macrophage Regular : tendons & ligaments Cartilage Chondroblast , Hyaline: few Fetal bones , chondrocyte. collagen. Shark skeleton Elastic: elastic Human ear. Fibrocartilage: Intervertebral large amount of discs collagen Bone Osteoprogenator , Collagen & Vertebrate osteoblast , elastic. skeletons. osteocyte , osteoclast Adipose Adipocyte Few Adipose (Fat) Blood Red blood cells , None Blood White blood cells , Platelets 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 18  Dr. mohamed-Elshebly 3 -- MUSCULAR TISSUE GENERAL FEATURES OF MUSCULAR TISSUE : 1 – Muscle tissue is composed of differeniated cells containing contractile proteins. 2 – Most muscle cells are mesodermal in origin. 3 – Muscle tissue is made up of cells that are called muscle fibers. 4 – Muscular terms : A – Cytoplasm = sarcoplasm. B – Cell membrane = sarcolemma. D -- SER = smooth sarcoplasmic reticulum. 5 – Cells of muscle are elongated. 6 – Muscle cells either striated or smooth muscle cells depending on presence or absence of regularly repeated arrangement of contractile proteins ( myofillaments ). 7 – Striated muscle cells show characteristics alteration of light & dark cross bands , which absence in smooth. TYPES OF MUSCLES : A ) Skeletal muscles : accounting for most of the voluntary musle mass of the body , which is composed of long , cylindrical , not branched , multinucleated muscle fibers. B ) Cardiac muscles : is of composed long , branched muscle fiber with a single , large , oval centrally placed nucleus. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 19 Dr. mohamed-Elshebly C ) Smooth muscle : is composed of short , spindle shaped muscle fibers , with a centrally placed nucleus. Types Skeleton Cardiac Smooth muscle muscle muscle Site Skeleton Heart Viscera + wall of blood vessels Control Voluntary Involuntary Involuntary Striation Striated Less striated Non- striated Contraction Quick Rhythmic Slow 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 20  Dr. mohamed-Elshebly 4 -- Nervous tissue General features of nervous tissue : 1 – Nervous system develops from the ectoderm. 2 – The specialized cells that constitute the functional units are called neurons. 3 – The nervous tissue organized anatomically into : A – Central nervous system ( Brain + spinal cords ) B – Peripheral nervous system ( cranial nerves + spinal nerves ) 4 – Within CNS the neurons are supported by neuroglia , whine in PNS the supporting cells is called Schwann cells. Types of cells in nervous system : 1 – neurons 2 – neuroglia cells ( which support & protect neurons ) Neurons :  Responsible for receptive , integrative & motor function of the nervous system  Neurons consist of a cell body that gives off a variable number of processes.  The cell body called soma ( perikaryoun ).  Like a typical cell contain mass of cytoplasm surrounded by cell membrane. 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 21 Dr. mohamed-Elshebly  The cytoplasm contain a large central nucleus with prominent nucleolus.  Also contain numerous mitochondria , lysosome , golgi & RER.  Polyribosome are scattered in the cytoplasm.  When these RER cisternae & polyribosomes are stained with basic dyes they appear as clump of basophilic material called Nissel bodies.  RER are also present in the dendrites region of the neuron , but absent at the axon hillock ( the region on the cell body where axon arises ).  Most adult neurons display only one centriole & it possess the 9+0 arrangement of microtubule , because neurons do not undergo cell division , their centriole are believed to br vestigial structures.  The processes arising from the cell body are two types : A – Dendrites :these are short branching process. B – Axon : one & long.  In dendrite , the nerve impulse travels toward the cell body whereas , in axon the impulse travels away from the cell body. ‫تحقيق النجاح له لذه لكن مساعدة الغير للوصول للنجاح له لذه‬ ‫اعظم‬. ‫محمد الشبلي‬.‫د‬ 2005 ‫ اعداد طب‬--- 0925121809 ‫محمد الشبلي‬.‫د‬ 22 ‫‪Dr. mohamed-Elshebly‬‬ ‫د‪.‬محمد الشبلي ‪ --- 0925121809‬اعداد طب ‪2005‬‬ ‫‪23‬‬