NTA Level 4 Semester One

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Introduction To Human Anatomy And Organization Of Organism CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Introduction To Human Anatomy And Organization Of Organism using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Term Used in Anatomy and Physiology Is generally divided into three components:- iii.Developmental anatomy Subdivisions of gross anatomy Subdivision of microscopic anatomy Introduction To Human Anatomy And Organization Of Organism Anatomical Position and Planes Upper limbs by the sides with the palms facing anteriorly Anatomical Planes . Transverse planes (horizontal) are planes passing through the body at right angles to the median and frontal planes. Terms of Relationship and Comparison Ventral …. Combined terms describing intermediate positional arrangements Terms of Laterality Structural Organization Levels of Organism Chemical level Tissue level Organ system level CHARACTERISTICS OF LIVING ORGANISM Organization: Metabolism Other characteristics includes Life depend upon the following environmental factors Oxygen: is a gas used in the process of releasing energy from nutrients SUMMARY EVALUATION References INTRODUCTION TO HUMAN ANATOMY AND ORGANIZATION OF ORGANISM Term Used in Anatomy and Physiology Definition of Terms The word anatomy is derived from a Greek word ( Ana-Tome): meaning cutting up into sections. Anatomy: It is a study of the body structures and physical relationship involved in between body systems. OR Is the study of the structures and relation between body parts. Is generally divided into three components:- i.Gross (macroscopic) anatomy: It is the study of structure as they appear in human body. ii.Microscopic anatomy: It is the study of structures by using microscope.The structures include cells ,tissues and molecules iii.Developmental anatomy It is the study of the structural changes that occur between conception and adulthood. Subdivisions of gross anatomy i.Surface anatomy It is the study of the external form of the body and its relation to deeper structures. ii.Regional anatomy It is the study of specific regions of the body iii.systemic anatomy It is the study of specific organ systems Subdivision of microscopic anatomy Cytology: The study of the structural features of cells using microscope. Histology: The study of tissues, which are group of cells and the material surrounding them. Is the study of tissue at microscopic level. Introduction To Human Anatomy And Organization Of Organism Physiology: The science of the mechanical, physical, and biochemical functions of humans in good health, their organs and the cells of which they are composed. Pathology: The medical science dealing with all aspects of disease, with an emphasis on the cause and development of abnormal conditions as well as the structural and functional impairement resulting from disease. Anatomical Position and Planes Anatomical Position All anatomical descriptions are expressed in relation to the anatomical position. The anatomical position refers to people regardless of the actual position they may be in as if they were standing erect, with their: Head, eyes (gaze), and toes directed anteriorly (forward) Upper limbs by the sides with the palms facing anteriorly Lower limbs close together with the feet parallel and the toes directed anteriorly ANATOMICAL POSITION … Anatomical Planes Anatomical descriptions are based on four imaginary planes that intersect the body in the anatomical position. There are many sagittal, frontal, and transverse planes, but there is only one median plane Introduction To Human Anatomy And Organization Of Organism Median (median sagittal) plane is the vertical plane passing longitudinally through the centre of the body, dividing it into right and left halves Sagittal planes are vertical planes passing through the body parallel to the median plane. Introduction To Human Anatomy And Organization Of Organism It is helpful to give a point of reference to indicate the position of a specific plane for example, a sagittal plane through the midpoint of the clavicle=mid clavicular line Any plane parallel and near the median plane may be referred to as a Para median plane Frontal (coronal) planes are vertical planes passing through the body at right angles to the median plane, dividing it into anterior (front) and posterior (back) portion for example, a frontal plane through the heads of the mandible. . Transverse planes (horizontal) are planes passing through the body at right angles to the median and frontal planes. A transverse plane divides the body into superior (upper) and inferior (lower) part for example, a transverse plane through the umbilicus is called transumbilical plane Terms of Relationship and Comparison The following terminologies describe the relationship of parts of the body in the anatomical position and compare the position of two structures relative to each other Anterior In front of, front Posterior After, behind, following, toward the rear Distal Away from, farther from the origin (trunk) Proximal Near, closer to the origin Dorsal Near the upper surface, toward the back Ventral Toward the bottom, toward the belly Superior Above, over or near to the head Inferior Below, under or near to the foot (in relation to other structure) Lateral Toward the side, away from the mid-line Medial Toward the mid-line, middle, away from the side Rostral Toward the front of the head (nose/mouth) Caudal Toward the back, toward the tail …. Cranial Combined terms describing intermediate positional arrangements Inferomedial Nearer to the feet and closer to the median plane for example, the anterior parts of the ribs run inferomedially Superolateral Nearer to the head and farther from the median plane Proximal and distal Directional terms used when describing positions for example, whether structures are nearer to the trunk or point of origin (i.e. proximal) Dorsum Superior or dorsal (back) surface of any part that protrudes anteriorly from the body, such as the dorsum of the foot, hand, penis, or tongue Terms of Laterality Paired structures having right and left members (e.g., the kidneys) are bilateral, whereas those occurring on one side only (e.g., the spleen) are unilateral. Ipsilateral means occurring on the same side of the body e.g. the right thumb and right great toe. Contra-lateral means occurring on the opposite side of

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Introduction to pathology CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Introduction to pathology using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic INTRODUCTION TO PATHOLOGY Pathological terminologies (100+ terms) Terms cont. EVOLUTION OF PATHOLOGY PATHOLOGY During this era Papanicolaou in 1930s developed the use of exfoliative cytology for early detection of cervical cancer. Infarction= cellular/tissue death as a result of ischemia/hypoxia Era of gross pathology (AD 1500 to 1800). SUBDIVISIONS OF PATHOLOGY ……. DISEASE DEVELOPMENT ENVIRONMENTAL FACTORS Dietary excess can the cause of many systemic diseases such as cardiac diseases. Hypersensitivity to various substances can lead to alarming shock-like conditions- anaphylaxis. The blood group Duffy negative confers resistance to infection by Plasmodium vivax. PATHOGENESIS Functional derangement and clinical importance CLASSIFICATIONS OF DISEASES Basing on body response disease can be classified into 4 categories namely :- 3) Degenerative = disease due to aging GENERAL PATHOLOGY INTRODUCTION TO PATHOLOGY By the end of this session, students are expected to be able to: Define pathology Understand evolution of pathology Identify subdivisions of pathology Explain disease development Classify categories of diseases Explain cell injury and cell death Pathological terminologies (100+ terms) Pathogenesis = course of disease = start–> end or terminal stage Necrosis = Irreversible abnormal cell death Apoptosis = programmed cell death Aetiology = cause of disease Ischemia= decreased blood flow to body tissue Hypoxia/hypoxemia= low oxygen content in blood Oxidative stress= imbalance between free radicals and antioxidants in the body Terms cont. Hypoxia= low oxygen supply in bodily tissue ROS= Reactive oxygen species are derivatives of oxygen that result from aerobic respiration eg peroxides, superoxide, hydroxyl radical OR Free radicals= oxygen containing molecules with uneven number of electrons (unstable) Antioxidant= any chemical substance that protects a cell from the damage caused by free radicals eg vitamins (A,C,E & K) , Uric acid, Glutathione, Enzymes ( Catalase) Lesion= an area of abnormal tissue FREE RADICALS V ANTIOXIDANTS EVOLUTION OF PATHOLOGY Evolution of Pathology began with the following concepts from different era : Religious and superstitious beliefs to rational approach (Antiquity to AD 1500). The earliest concepts of disease were the religious and superstitious beliefs that affliction or disease was the outcome of curse or evil eye of spirits. The real practice of medicine began in the 460 to 377 BC (Before Christ). Hippocrates introduced ethical concepts in the practice of medicine and admired/respected by the medical profession by taking Hippocratic oaths at the time of entry into practice of medicine. PATHOLOGY The word pathology is derived from Greek words Pathos=suffering and logos= the study Definitions: It is a branch of medicine which deals with the study of the nature (aetiology) and the course (mechanisms) of disease. It is a scientific study of structure and function of the body in disease. During this era Papanicolaou in 1930s developed the use of exfoliative cytology for early detection of cervical cancer. Era of modern pathology (1960s to dawn of 21st century) The major advances in molecular biology in the field of diagnosis and treatment of genetic disorders, immunology and in cancer. These includes:- The description of the structure of DNA Identification of chromosomes and their numbers Recombinant DNA technique Mammalian cloning Infarction= cellular/tissue death as a result of ischemia/hypoxia Inflammation= local response of vascularized tissue to noxious stimuli that causes cellular injury Inflammatory mediators= chemical substances released by cells in response to stimuli causing inflammation [proteins , peptides, glycoprotein ,cytokines ,prostaglandins(Histamine, ] Era of gross pathology (AD 1500 to 1800). In this era the discovery of science in diagnosis involved studies by dissection of human body, autopsy, and the use of microscope in examining the diseased tissues. Era of technology development and cellular pathology (AD 1800 to 1950s). This era the technology of microscopy was advanced to involve, different staining methods or techniques, the use of electron microscope to examine and view ultra structure of the cell and its organelles SUBDIVISIONS OF PATHOLOGY (1)Human pathology is the largest branch of pathology It is conventionally divided into (a)General pathology Which deals with general principles of disease i.e. is concerned with the basic reaction of cells and tissue to abnormal stimuli that underlies all diseases (b)Systemic pathology Includes study of diseases pertaining to the specific organs and body systems. This examine the specific responses of specialized organs and tissue to more or less well defined stimuli (2) Histopathology used synonymously with anatomic pathology (pathologic) anatomy, or morbid anatomy, is the classic method of study and still the most useful one which has stood the test of time. ……. Histopathology is divided into:- (a) Surgical pathology which deals with study of tissues removed from the living body. (b) Forensic pathology and autopsy work includes the study of organs and tissues removed at post-mortem. (3) Cytopathology includes study of cells shade off from lesions (exfoliative cytology and fine needle aspiration cytology of superficial and deep seated lesions for diagnosis). DISEASE DEVELOPMENT This is loss of ease of body Any harmful deviation from the normal structural or functional state of an organism. It is the opposite of health, what is not healthy is diseased The four aspects of a disease process that form the core of pathology are Its cause or aetiology The mechanisms of its development, pathogenesis The structural alterations induced in the cells and organs of the body, morphologic changes The functional consequences of the morphologic changes, clinical significance Introduction to pathology Knowledge or discovery of the primary cause remains the backbone on which a diagnosis can be made, a disease understood or a treatment developed There are two major classes of aetiologic factors o Intrinsic or genetic o Acquired/Environmental factor Genetic factors are clearly involved in some of the common environmentally induced maladies, such as cancers and atherosclerosis The environment may also have profound influences on certain genetic diseases ENVIRONMENTAL FACTORS Are many and are classified as follows : Physical agents, among these are trauma,

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Organs In Different Body Cavity CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Organs In Different Body Cavity using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Body Cavity Main Body Cavities The Ventral Body Cavities Organs-(Abdominal-Pelvic Cavity) …. Male reproductive organs (prostate, part of ductus deferens). Thoracic Cavity and its Divisions The Mediastinum Regions(subdivision) of mediastinum The middle mediastinum The superior mediastinum The anterior mediastinum Peritoneum and Peritoneal Cavity CT ORGANS IN DIFFERENT BODY CAVITIES Body Cavity Body cavities: spaces within the body that help protect, separate and support internal organs. Body cavity is any fluid filled space in a multicellular organism. Main Body Cavities The two major cavities of the body are The dorsal cavity The ventral body cavities. The Dorsal Cavity The dorsal body cavity is located near the posterior surface of the body and has two main subdivisions The vertebral canal that contains the spinal cord The cranial cavity that contains the brain The Ventral Body Cavities The ventral body cavity is located near the anterior surface of the body and has two subdivisions The thoracic cavity The abdomino-pelvic cavity The abdomino-pelvic cavity, which is separated by the diaphragm consists of two continuous cavities -The abdominal cavity -The pelvic cavity Organs-(Abdominal-Pelvic Cavity) Abdominal cavity contains Stomach Liver Gallbladder Pancreas Spleen small intestine Kidneys Appendix part of the large intestine. …. The pelvic cavity contains Part of the large intestine Rectum Urinary bladder Female reproductive organs (ovaries, uterine tubes, uterus, vagina) Male reproductive organs (prostate, part of ductus deferens). It is important to note that the testes and penis are not located in the ventral body cavity but are outside the body wall. Thoracic Cavity and its Divisions Thoracic Cavity: Space enclosed by the ribs, sternum, and vertebral column The thoracic cavity is separated from the abdominal cavity by the diaphragm. This cavity contains three small cavities (potential spaces). The pericardial cavity (peri _around; cardia _ heart). Two pleural cavities (pleura _ side or rib). The pericardial cavity surrounds the heart, and each pleural cavity contains a lung. The Mediastinum A broad central partition that separates the two laterally placed pleural cavities. Extends from the sternum to the bodies of the vertebrae and from the superior thoracic aperture to the diaphragm. The organs located in the mediastinum are the heart, thymus gland, oesophagus, trachea and bronchi. The pleural cavities are located on either side of the mediastinum Regions(subdivision) of mediastinum The middle mediastinum The superior mediastinum The anterior mediastinum The posterior mediastinum The middle mediastinum Centrally located in the thoracic cavity. Major Structures found heart, origins of the great vessels, various nerves smaller vessels. The superior mediastinum The superior mediastinum is posterior to the manubrium of the sternum and anterior to the bodies of the first four thoracic vertebrae. The superior mediastinum is continuous with the neck superiorly and with the inferior mediastinum inferiorly. The Major Structures found include: Thymus Right and left brachiocephalic veins Left superior intercostal vein Superior vena cava Arch of the aorta with its three large branches …. Trachea Esophagus Phrenic nerves Vagus nerves Left recurrent laryngeal branch of the left vagus nerve Thoracic duct Other small nerves, blood vessels, and lymphatics The anterior mediastinum Posterior to the body of the sternum Anterior to the pericardial sac. The posterior mediastinum Posterior to the pericardial sac and diaphragm Anterior to the bodies of the mid and lower thoracic vertebrae. Major structures in the posterior mediastinum Esophagus and its associated nerve plexus Thoracic aorta and its branches Azygous system of veins Thoracic duct and associated lymph nodes Sympathetic trunks Thoracic splanchnic nerves Peritoneum and Peritoneal Cavity The peritoneum is the largest serous membrane in the body The abdominal cavity is lined by peritoneum, which consists of an epithelial-like single layer of cells (the mesothelium) together with a supportive layer of connective tissue. Two layers Parietal peritoneum lines the abdominal wall. Visceral peritoneum covers suspended organs The peritoneal cavity is a potential space between the parietal peritoneum Contains a small amount of serous fluid CT Abdominal viscera are either intraperitoneal or retroperitoneal Intraperitoneal structures are suspended from the abdominal wall by mesenteries Stomach Liver Gallbladder Spleen small intestine …. Appendix large intestine Rectum Urinary bladder Female reproductive organs (ovaries, uterine tubes, uterus, vagina) Male reproductive organs (prostate, part of ductus deferens). CT Structures that are not suspended in the abdominal cavity by a mesentery and that lie between the parietal peritoneum and abdominal wall are retroperitoneal in position includes; The kidneys Ureters Pancreas Great vessels ( aorta and venna cava) ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? 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DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Structure and Functions of Epithelial Tissues CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Structure and Functions of Epithelial Tissues using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic EPITHELIAL TISSUE Structure of Epithelial Tissues It also forms all glands including endocrine and exocrine glands Classification of Epithelial Tissues Simple Epithelium Simple Cuboidal Epithelium Stratified Epithelia Stratified squamous epithelium Non keratinized stratified epithelium Transitional Epithelia General Functions of Epithelial Tissues General Functions of Epithelial Tissue Secretion summary assignment reference Structure and Functions of Epithelial Tissues EPITHELIAL TISSUE What is epithelial tissue? EPITHELIAL TISSUE Epithelial tissues are linings of the various passages inside the body. Structure of Epithelial Tissues General Structure of Epithelial Tissues Epithelium is a group of closely associated cells with scanty intercellular materials that cover external and internal surfaces of the body They form the covering of all body surfaces, line body cavities and hollow organs, and are the major tissue in glands Epithelial tissues are widely spread throughout the body The cells in epithelial tissue are tightly packed together with no intercellular material between the cells or very little intercellular materials It also forms all glands including endocrine and exocrine glands The cells are attached to the underlying connective tissue known as the basement membrane The basement membrane is a connective tissue structure where the epithelial cells are attached Cells of epithelial tissue appear in different shapes and structure These differences reflect the functions of the epithelium Classification of Epithelial Tissues what are the classes of epithelial tissue? Classification of Epithelial Tissues Classification according to the cell shape Squamous epithelia:cells are flat cells with an irregular flattened shape (fish-scale appearance) Cuboidal eithelia:cells have a shape similar to a cube, meaning its width is the same size as its height Columnar epithelia: cells are taller than they are wide Classification based on number of cell layers (Stratification) Simple epithelia Stratified epithelia Pseudostratified epithelia Transitional epithelia Simple Epithelium Cells are organized in a single layer and therefore all cells are attached to the basement membrane Because the shapes of the cells include possible function, they are found in different organs depending on their function: There are three types of simple epithelium: Simple squamous epithelium, Simple cuboidal epithelium, Simple columnar epithelium Simple Squamous Epithelium All Squamous cells are flat cells with an irregular flattened shape It is a one-cell layer of simple squamous epithelium Forms a thin membrane and therefore it is found in places where exchange of material from one compartment to the other occurs. Squamous cells can be found in the heart, blood vessels, lymph vessels and alveoli of the lung. They allow free diffusion Simple Cuboidal Epithelium This consists of cube-shaped cells fitting closely together lying on a basement membrane. Forms secretory cells, lining of the small ducts of the glands and it covers the outer surfaces of organs such as the ovaries and in the kidney tubules Are actively involved in secretion, absorption and excretion Simple Columnar Epithelium This is formed by a single layer of cells, rectangular in shape lying on a basement membrane. It is found lining the organs of the alimentary tract. Consists of mixture of cells, some absorb the products of digestion and others secrete mucus. Stratified Epithelia Consists of several layers of cells of various shapes The superficial layers grow up from below Basement membranes are usually absent The main function of compound epithelium is to protect underlying structures There are two types: Stratified and transitional Stratified squamous epithelium Consists of several layers of cells of different shapes The cells are arranged into superficial, intermediate and basal (deep) layers In the deepest layers the cells are mainly columnar and, as they grow towards the surface, they become flattened. It is the main protective epithelium of the body external surface for example in the skin it forms the epidermis,some parts of tongue, hard palate There are two types: Non keratinized stratified epithelium and Keratinized stratified epithelium Keratinized stratified epithelium Refers to cells that has become hardened and died. The cells have a tough fibrous protein called keratin that helps protect the skin and underlying tissues from heat, microbes and chemicals. It is found on dry surfaces that are subject to wear and tear such as skin, hair and nails. Non keratinized stratified epithelium Does not contain keratin and consists of cells which are not dead It is found on wet surfaces that may be subjected to wear and tear but are protected from drying, for example conjunctiva of the eyes, and lining of the mouth, pharynx, the oesophagus and vagina. It provides mechanical protection from injury Transitional Epithelia Transitional epithelium: A transitional epithelium (also known as urothelium) is made up of several layers of cells that become flattened when stretched. It lines most of your urinary tract and allows your bladder to expand. General Functions of Epithelial Tissues What are the functions of epithelial tissues? General Functions of Epithelial Tissue Protection Epithelial cells from the skin protect underlying tissue from mechanical injury, harmful chemicals, invading bacteria and from excessive loss of water Sensation Sensory stimuli penetrate specialized epithelial cells Specialized epithelial tissue containing sensory nerve endings is found in the skin, eyes, ears, nose and on the tongue Secretion In glands, epithelial tissue is specialized to secrete specific chemical substances such as enzymes, hormones and lubricating fluids Absorption Certain epithelial cells lining the small intestine absorb nutrients from the digestion of food Excretion Epithelial tissues in the kidney excrete waste products from the body and reabsorb needed materials from the urine Sweat is also excreted from the body by epithelial cells in the sweat glands Diffusion Simple epithelium promotes the diffusion of gases, liquids and nutrients summary The term "epithelium" refers to layers of cells that line hollow organs and glands It is also those cells that make up the outer surface of the body. Cells of epithelial tissue appear

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Bones and Disorders of Connective Tissue CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Bones and Disorders of Connective Tissue using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Structure and Functions of Bone Tissues Definition Of Bone Bones and Disorders of Connective Tissue Bone consists of: Bone Cells; The bone contains four types of cells namely the osteoprogenator cells, osteoblasts, osteocytes, and the osteoclasts Types of Bones Parts of the long bone Bones Formation Bones formation occurs in four main stages which are Functions of Bones Movement KEYPOINTS QUESTIONS Common Disorders of Common Disorders of Connective Tissues Common Types of Connective Tissue Diseases Acute pyrogenic arthritis Gout The disease is commonest in men over 40 years. Chronic joint disease Osteoarthritis Generalized bone disease Osteomalacia Structure and Functions of Bone Tissues PHARM. EMERENCIANA M. JAMES Definition Of Bone Bone is a hard and rigid tissue that forms the bony skeleton of the body. Bone supports the body weight, It provides attachment to muscles, Acts as lever for movements, and provides protection to organs Inside the bone there are spaces, which are filled with the bone marrow that produce red blood cells, platelets and cells of the immune system Bones and Disorders of Connective Tissue Cells of the immune system produced in bone marrow include monocytes, lymphocytes, mast cells, neutrophils, eosinophils and basophils The only difference with other connective tissues is that its ground substance is made up of inorganic salts, mostly calcium ions The bone is highly vascularized, and in living conditions the bone appears pinkish in colour Bone consists of: Cells Fibers Ground substances Bone Cells; The bone contains four types of cells namely the osteoprogenator cells, osteoblasts, osteocytes, and the osteoclasts Bone Matrix (Intercellular substance);It is made up of the collagen fibers (osteocollagenous fibers), amorphous ground substance and inorganic salts which constitute about 74% of bone mass Types of Bones Long bones e.g. femur, tibia and fibula Short bones e.g. carpals (wrist bones) Flat bones e.g. sternum, ribs and most skull bones (skull) Irregular bones e.g. vertebrae and some skull bones Sesamoid bones e.g. patella (kneecap) Parts of the long bone A long bone is one that has greater length than width. A typical long bone consists of the following parts: The diaphysis is the bone’s shaft or body—the long, cylindrical, main portion of the bone. The epiphyses (singular is epiphysis) are the proximal and distal ends of the bone. The metaphyses (singular is metaphysis) are the regions between the diaphysis and the epiphyses. Bones Formation Bones formation is commonly referred to as ossification and it occurs in two processes Intramembranous Ossification The bones that form by this process include most of skull bones such as frontal,parietal, maxilla, mandible, clavicle and parts of occipital and temporal bones. Endochondral Ossification In endochondral ossification bone is formed from the pre-existing hyaline cartilage that has the shape that closely resembles the bone to be formed. Bones and Disorders of Connective Tissue Most long and irregular bones form via endochondral ossification, such as the base of the skull, vertebral column, the pelvis and bones of the extremities (limbs). During this process the cartilage is gradually replaced by bone. Only a small amount of cartilage remains covering the articular surfaces of the joints. During endochondral ossification the bone also grows in length and width. Generally flat bones develop by intramembranous ossification while long bones develop by intra cartilaginous ossification Bones formation occurs in four main stages which are Development of the ossification canters (special membrane) Formation of bone matrix Deposition of minerals or calcification Formation of trabeculae and appearance of periosteum Functions of Bones Support The skeleton serves as the structural framework for the body by supporting soft tissues providing attachment points for the tendons of most skeletal muscles Protection The skeleton protects the most important internal organs from injury for example, cranial bones protect the brain, vertebrae (backbones) protect the spinal cord, and the ribcage protects the heart and lungs. Movement When muscles contract, they pull on bones to produce movement. Mineral homeostasis (storage and release); Bone tissue stores several minerals, especially calcium and phosphorus, which contribute to the strength of bone Blood cell production; bone marrow produces red blood cells, white blood cells, and platelets, a process called hemopoiesis KEYPOINTS Bone is a hard and rigid connective tissue that forms the bony skeleton of the body Functions of bones Bone supports the body weight, It provides attachment to muscles, Acts as lever for movements, and provides protection to organs. Inside the bone there are spaces, which are filled with the bone marrow that produce Red blood cells, platelets and cells of the immune system. Production of body cells: monocytes, lymphocytes, mast cells, neutrophils, eosinophils and basophils QUESTIONS What is bone tissue? What are the types of bones? What are the functions of bones? Common Disorders of Connective Tissues PHARM. EMERENCIANA M. JAMES Common Disorders of Connective Tissues A connective tissue diseases are diseases that affect the joints (parts of the body that connect the structures of the body together). It is presented by the inflammation of the joints (arthritis) It may be infective or non-infective. In most cases, all signs of inflammation are present (swollen joints, hot, tender and red) and there is limitation of movements Common Types of Connective Tissue Diseases Acute pyrogenic arthritis Gout Chronic joint disease Osteoarthritis Generalized bone disease Osteomalacia Osteoporosis Acute pyrogenic arthritis This is the infection of the joints by pus-producing bacteria It is caused by any pyrogenic bacteria like staphylococci. The infection may start suddenly without any obvious cause or may occur from other septic focus nearby like osteomyelitis The patients complain of pain, swelling and reduced movement of the joint Gout This is arthritis due to congenital abnormality of uric acid metabolism, leading to abnormal high uric acid in the blood. Uric acid is deposited in joints and also around the