CRT04101 Anatomy, Physiology and Pathology

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Disorders Of Gi Tract CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Disorders Of Gi Tract using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Regardless of the cause and type of a disease Gastrointestinal (GI )pathologies have the following presenting features; Abdominal pain Disorders Of Gi Tract Nausea and Vomiting Gastroesophageal Reflux Disease (GERD) Heartburn GI bleeding GI motility disorders Hernia Jaundice DISORDERS OF GI TRACT Regardless of the cause and type of a disease Gastrointestinal (GI )pathologies have the following presenting features; Abdominal pain GI bleeding Diarrhoea Steatorrhea Constipation Nausea Vomiting Dysphagia Odynophagia Gastroesophageal reflux Anorexia Weight loss Abdominal pain Pain originates from tissue injury, distention, contraction, inflammation, and direct chemical injury.Visceral pain is often poorly localized and loosely corresponds to the spinal segment that innervates the involved viscus. Somatoparietal pain arises from noxious stimulation of the parietal peritoneum. Diarrhoea An increased number or fluidity of stools is usually due to an excess of water in stool. Most people have experienced loose stools for a day or two (e.g. viral gastroenteritis), but other causes, such as inflammatory bowel disease, can be chronic and cause intermittent symptoms for a patient's entire lifetime. Disorders Of Gi Tract Diarrhoea results from either an increase in secretion or decrease in absorption or both.It is classified as : secretory or osmotic diarrhoea Bloody diarrhoea occurs with mucosal inflammation or erosions or ulcerations secondary to infectious, inflammatory, or ischemic entero-colitis. Blood in the stool always implies an underlying organic abnormality. Constipation It is characterised by difficult in passage of stool.It occurs most commonly in elderly and often used to describe more than one symptom, including: Infrequent stools A sense of incomplete evacuation Abdominal bloating or discomfort Treatment plans vary, but the simplest and most common starting point is to increase the patient's daily fibre and fluid intake. Nausea and Vomiting Nausea and vomiting may be manifestations of GI diseases or primary non-GI diseases and may lead to fluid and electrolyte imbalances, nutritional deficiencies, aspiration pneumonia and oesophageal rupture Nausea is the unpleasant sensation of the desire to vomit Retching, is coordinated voluntary muscle activity of the abdomen and chest without discharge of stomach contents into the mouth. Vomiting, or the act of emesis, occurs as gastric contents are forcefully ejected out of the mouth Nausea and vomiting may be acute, such as with acute obstruction, inflammation, or ischemia, other acute infections, medication, pregnancy or head trauma. Disorders Of Gi Tract Nausea and vomiting that are chronic in nature are usually associated with pregnancy, medications, and motility disorders such as diabetic, gastroparesis, partial obstruction, intracranial disease, psychogenic disorders, or an underlying metabolic or endocrine disturbance. Dysphagia Is the sensation of solids or liquids not passing from the mouth into the stomach.It is a common symptom and can be divided into: oropharyngeal dysphagia and oesophageal dysphagia. Oesophageal dysphagia is caused by either : Motility disorder, such as achalasia, diffuse oesophageal spasm, or scleroderma. Mechanical obstruction, such as a benign stricture, ring, or neoplasm. Gastroesophageal Reflux Disease (GERD) The terms heartburn, acid regurgitation, sour stomach, and bitter taste are all used to describe GERD symptoms.Reflux occurs when the oesophageal epithelium is exposed to gastric secretions. Some degree of gastric reflux is considered normal, but symptoms occur when the mucosa's tolerance to acid is exceeded. In addition to the typical symptoms of heartburn or chest pain, extra-oesophageal manifestations of GERD include laryngitis, asthma, and chronic cough GERD develops when acidic gastric contents reflux into the oesophagus and remain there long enough to overcome the resistance of the oesophageal epithelium. Heartburn Is typically a burning pain or discomfort that rises up the retro sternum arises from dyspepsia.Dyspepsia refers to persistent or recurrent epigastric pain or meal-related upper abdominal discomfort that may be characterized by early satiation or postprandial fullness Anorexia and Early Satiety Anorexia is loss of the desire to eat and is a major symptom in many GI and non-GI diseases, including central nervous system, systemic, and psychological disorders. Common causes include; Delayed gastric emptying such as occurs in long-term diabetes mellitus Decreased gastric distention secondary to gastric malignancy Gastric outlet obstruction caused by peptic ulcer disease GI bleeding GI bleeding can be either acute or chronic, and it can be massive or occult. Upper GI bleeding may be manifested as Hematemesis(vomiting blood) Lower GI bleeding may be manifested as; 1.Melena (black stool) 2.Haematochezia (Blood in stool) Esophageal varices also lead to upper GI bleeding The two most common causes of acute lower GI bleeding are diverticulosis and arterio-venous malformations. Occult bleeding is defined as the detection of asymptomatic blood loss from the gastrointestinal tract, generally by routine faecal occult blood testing or the presence of iron deficiency anaemia. GI motility disorders Intestinal obstruction Is a blockage that keeps food or liquid from passing through either small intestine or large intestine. There are two main causes of intestinal obstruction,which are; 1.Mechanical obstruction This may be due to extrinsic or intrinsic blockage factors such as Adhesions(Post abd surgery pt),volvulus (twisting of either ceacum or sigmoid colon),intussusception in pediatric patients and fecal impaction. 2.Paralytic ileus This occurs when the muscle of the intestine are paralyzed,preventing peristalsis Hernia Is a defect occurred on a membranous tissue or cavity.It can be congenital or acquired. There are three types of hernia,which are; 1.Reducible hernia 2.Incarcerated hernia 3.Strangulated hernia Other forms of hernia are hiatus,inguinal, Jaundice Is a yellowish discolouration of eye or skin caused by excessive bilirubin(hyperbilirubinemia).Bilirubin is a nitrogenous waste produced after death of red blood cells and is filterd by liver.There are two types of jaundice,which are; 1.Obstructive jaundice, Caused by blockage of biliary tree that lead to poor supply of bile.Bile is stored within Gall bladder 2.Non-obstrucutive jaundice, Caused by poor production of bile due to liver parenchyma diseases ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Structure and Functions of Nervous Tissues CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Structure and Functions of Nervous Tissues using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic NERVOUS TISSUES Nervous tissue or nerve tissue: Components of Nervous Tissue A Typical Neuron Consist of: Types of Neuron Classification of Neurons according to their Functional Roles Neuroglia and their Functions Neuroglia (Glial Cells) : II.Microglia Glia Cells Found in the Peripheral Nervous System Key points evaluation Structure and Functions of Nervous Tissues NERVOUS TISSUES What is nervous tissue? Nervous tissue or nerve tissue: Is the main tissue component of the two parts of the nervous system; the brain and spinal cord of the central nervous system (CNS), and the branching peripheral nerves of the peripheral nervous system (PNS), which regulates and controls bodily functions and activity. Nervous tissue is distributed throughout the body as an integrated communicating network Components of Nervous Tissue Structurally, nerve tissue consists of two classes of cell types. Neurons, the nervous tissue is made up of billions of cells called neurons that are specialized to respond to stimuli and to transmit a signal to activate other cells. Glial cells or neuroglia, non-excitable supporting cells, participate in neural activity, neural nutritional and defence processes of the central nervous system. A Typical Neuron Consist of: Cell body, which has many radiating processes called dendrites, which are specialized to receive signals from other neurons. Axon, a single long process, which is capable of generating a nerve impulse and conducting it over a long distance to stimulate other neurons in the CNS, or muscular or secretory cells elsewhere in the body. Neurons usually receive information through dendrites; the information is integrated in the cell body and transmitted onwards via axons. Types of Neuron Unipolar neurons, these neurons have single processes, the axon arising from the cell body. Unipolar neurons have no dendrites. Bipolar neurons, have two processes (both axons) emerging directly and oppositely from the cell body. Bipolar neurons are found in the cochlear and vestibular ganglia as well as retina and olfactory mucosa. Multipolar neurons, has one axon and many dozens of dendrites. Most neurons in the CNS are multipolar ( +all motor neurones) Pseudo unipolar neurons, has a single short process (an axon) with a T-shaped branching, one branch extending towards the CNS, and the other extending to a periphery ending. In typical pseudo unipolar neurons, both branches are axons on both structural and electrophysiological grounds. Classification of Neurons according to their Functional Roles Motor neurons are involved in stimulating muscles or glands (effector organs) in the periphery. Sensory neurons, sensory neurons receive sensory stimuli from the environment or from tissues and organs of the body. Interneurons, maintain connection between neurons in the CNS, forming complex function chains or circuits. Neuroglia and their Functions What is neuroglia? Neuroglia (Glial Cells) : These are supporting cells found in the central nervous system and peripheral nervous system There are six types of supporting cells Four are found in the CNS and two are found in the PNS Neuroglia found in central nervous system are : I.Astrocytes Star-shaped, abundant, and versatile Guide the migration of developing neurons, they are found in large numbers adjacent to blood vessels They form a blood-brain barrier (BBB), i.e. the blood is separated from neurones by capillary wall and a layer of astrocytes foot process II.Microglia Specialized immune cells that act as the macrophages of the CNS They derived from monocytes III.Ependymal Cells These cells form the epithelial lining of the ventricles of the brain and the central canal of the spinal cord IV. Oligodendrocytes, These are found in clusters around cell bodies They form and maintain the myelin, having the same functions as schwann cells in peripheral nerves These cells have clinical importance as most tumours of the brain are arising from them Glia Cells Found in the Peripheral Nervous System V.Satellite cells, surround clusters of neuronal cell bodies in the PNS, they are of unknown function VI.Schwann cells, form myelin sheaths around the larger nerve fibers in the PNS, they are for neuronal regeneration Key points The nervous system is composed of neurons (nerve cells) and neuroglia (protective and supporting cells) Neurons are sensitive to stimuli, convert stimuli into electrical signals called action potentials (nerve impulses), and conduct nerve impulses. Neuroglia (Glial Cells) are supporting cells found in the central nervous system and peripheral nervous system evaluation What is nervous tissue? What are the components of nervous tissue? What are the types of neuron types? What are the types of neuroglia and their functions? What are the function of neuroglia? ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Body Functions and Life Processes CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Body Functions and Life Processes using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Anatomy and Physiology – Body Functions and Life Processes BODY FUNCTIONS & LIFE PROCESS Body Functions Body functions are the physiological or psychological functions of body systems. The body's functions are ultimately its cells' functions. Survival is the body's most important business. Survival depends on the body's maintaining or restoring homeostasis, a state of relative constancy, of its internal environment. More than a century ago, French physiologist, Claude Bernard (1813-1878), made a remarkable observation. He noted that body cells survived in a healthy condition only when the temperature, pressure, and chemical composition of their environment remained relatively constant. Later, an American physiologist, Walter B. Cannon (1871-1945), suggested the name homeostasis for the relatively constant states maintained by the body. Homeostasis is a key word in modern physiology. It comes from two Greek words – "homeo," meaning the same, and "stasis," meaning standing. "Standing or staying the same" then is the literal meaning of homeostasis. However, as Cannon emphasized, homeostasis does not mean something set and immobile that stays exactly the same all the time. In his words, homeostasis "means a condition that may vary, but which is relatively constant." Homeostasis depends on the body's ceaselessly carrying on many activities. Its major activities or functions are responding to changes in the body's environment, exchanging materials between the environment and cells, metabolizing foods, and integrating all of the body's diverse activities. The body's ability to perform many of its functions changes gradually over the years. In general, the body performs its functions least well at both ends of life – in infancy and in old age. During childhood, body functions gradually become more and more efficient and effective. During late maturity and old age the opposite is true. They gradually become less and less efficient and effective. During young adulthood, they normally operate with maximum efficiency and effectiveness. Life Process All living organisms have certain characteristics that distinguish them from non-living forms. The basic processes of life include organization, metabolism, responsiveness, movements, and reproduction. In humans, who represent the most complex form of life, there are additional requirements such as growth, differentiation, respiration, digestion, and excretion. All of these processes are interrelated. No part of the body, from the smallest cell to a complete body system, works in isolation. All function together, in finetuned balance, for the well being of the individual and to maintain life. Disease such as cancer and death represent a disruption of the balance in these processes. The following are a brief description of the life process: Organization At all levels of the organizational scheme, there is a division of labor. Each component has its own job to perform in cooperation with others. Even a single cell, if it loses its integrity or organization, will die. Metabolism Metabolism is a broad term that includes all the chemical reactions that occur in the body. One phase of metabolism is catabolism in which complex substances are broken down into simpler building blocks and energy is released. Responsiveness Responsiveness or irritability is concerned with detecting changes in the internal or external environments and reacting to that change. It is the act of sensing a stimulus and responding to it. Movement There are many types of movement within the body. On the cellular level, molecules move from one place to another. Blood moves from one part of the body to another. The diaphragm moves with every breath. The ability of muscle fibers to shorten and thus to produce movement is called contractility. Reproduction For most people, reproduction refers to the formation of a new person, the birth of a baby. In this way, life is transmitted from one generation to the next through reproduction of the organism. In a broader sense, reproduction also refers to the formation of new cells for the replacement and repair of old cells as well as for growth. This is cellular reproduction. Both are essential to the survival of the human race. Growth Growth refers to an increase in size either through an increase in the number of cells or through an increase in the size of each individual cell. In order for growth to occur, anabolic processes must occur at a faster rate than catabolic processes. Differentiation Differentiation is a developmental process by which unspecialized cells change into specialized cells with distinctive structural and functional characteristics. Through differentiation, cells develop into tissues and organs. Respiration Respiration refers to all the processes involved in the exchange of oxygen and carbon dioxide between the cells and the external environment. It includes ventilation, the diffusion of oxygen and carbon dioxide, and the transport of the gases in the blood. Cellular respiration deals with the cell's utilization of oxygen and release of carbon dioxide in its metabolism. Digestion Digestion is the process of breaking down complex ingested foods into simple molecules that can be absorbed into the blood and utilized by the body. Excretion Excretion is the process that removes the waste products of digestion and metabolism from the body. It gets rid of by-products that the body is unable to use, many of which are toxic and incompatible with life. The ten life processes described above are not enough to ensure the survival of the individual. In addition to these processes, life depends on certain physical factors from the environment. These include water, oxygen, nutrients, heat, and pressure. ANATOMICAL TERMINOLOGY Before we get into the following learning units, which will provide more detailed discussion of topics on different human body systems, it is necessary to learn some useful terms for describing body structure. Knowing these terms will make it much easier for us to understand the content of the following learning units. Three groups of terms

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Anatomy and Physiology – Introduction CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Anatomy and Physiology – Introduction using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Anatomy and Physiology – Introduction ANATOMY AND PHYSIOLOGY By ANATOMY AND PHYSIOLOGY The Anatomy and Physiology module introduces the structure and function of the human body. You will read about the cells, tissues and membranes that make up our bodies and how our major systems function to help us develop and stay healthy. In this module you will learn to: Describe basic human body functions and life process. Name the major human body systems and relate their functions. Describe the anatomical locations, structures and physiological functions of the main components of each major system of the human body. INTRODUCTION TO THE HUMAN BODY Human beings are arguably the most complex organisms on this planet. Imagine billions of microscopic parts, each with its own identity, working together in an organized manner for the benefit of the total being. The human body is a single structure but it is made up of billions of smaller structures of four major kinds: Cells Cells have long been recognized as the simplest units of living matter that can maintain life and reproduce themselves. The human body, which is made up of numerous cells, begins as a single, newly fertilized cell. Tissues Tissues are somewhat more complex units than cells. By definition, a tissue is an organization of a great many similar cells with varying amounts and kinds of nonliving, intercellular substance between them. Organs Organs are more complex units than tissues. An organ is an organization of several different kinds of tissues so arranged that together they can perform a special function. For example, the stomach is an organization of muscle, connective, epithelial, and nervous tissues. Muscle and connective tissues form its wall, epithelial and connective tissues form its lining, and nervous tissue extends throughout both its wall and its lining. Systems Systems are the most complex of the component units of the human body. A system is an organization of varying numbers and kinds of organs so arranged that together they can perform complex functions for the body. Ten major systems compose the human body: Skeletal Muscular Nervous Endocrine Cardiovascular Lymphatic Respiratory Digestive Urinary Reproductive Anatomy is the study of the structure and relationship between body parts. Physiology is the study of the function of body parts and the body as a whole. The structure of an organism or any of its parts. The scientific study of the shape and structure of organisms and their parts. Anatomy Definition. The structure of an animal or plant; also, the study of this structure through techniques such as microscopic observation and dissection. Anatomy is the branch of biology concerned with the study of the structure of organisms and their parts. In some of its facets, anatomy is related to embryology and comparative anatomy, which itself is closely related to evolutionary biology and phylogeny. Human anatomy is one of the basic essential sciences of medicine. The history of anatomy is characterized by a progressive understanding of the functions of the organs and structures of the human body. Methods have also improved dramatically, advancing from the examination of animals by dissection of carcasses and cadavers (corpses) to 20th century medical imaging techniques including X-ray, ultrasound, and magnetic resonance imaging. Anatomy and physiology, which study (respectively) the structure and function of organisms and their parts, make a natural pair of related disciplines, and they are often studied together. Anatomy is the scientific study of the structure of organisms including their systems, organs and tissues. It includes the appearance and position of the various parts, the materials from which they are composed, their locations and their relationships with other parts. Anatomy is quite distinct from physiology and biochemistry, which deal respectively with the functions of those parts and the chemical processes involved. For example, an anatomist is concerned with the shape, size, position, structure, blood supply and innervation of an organ such as the liver; while a physiologist is interested in the production of bile, the role of the liver in nutrition and the regulation of bodily functions Anatomical Structure of human body ← PREVIOUS TOPICNEXT TOPIC →VIEW ALL MODULE NOTESVIEW SEMESTER NOTESVIEW ALL LEVEL NOTESALL DIAGNOSTIC RADIOLOGY NOTES Need These Notes as PDF? Need a clean, well-formatted PDF copy for offline study, revision or printing? Request the complete notes directly through WhatsApp. GET WELL-FORMATTED PDF NOTES

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Vertebral Column-Structure & Functions CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Vertebral Column-Structure & Functions using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Vertebral Column Curvatures CT Vertebral Column-Structure & Functions Curvatures of Vertebral Column Structure and Function of Vertebrae The vertebral arch and the posterior surface of the vertebral body form the walls of the vertebral foramen. Seven Processes Arise From the Vertebral Arch of a Typical Vertebra Functions of the Vertebral Column Sacrum and Cocygeal Vertebrae STRUCTURE AND FUNCTIONS OF VERTEBRAL COLUMN Vertebral Column Curvatures The Vertebral Column The adult vertebral column typically consists of 33 vertebrae arranged in five regions: 7cervical, 12 thoracic, 5 lumbar, 5 sacral, and 4 coccygeal. CT The typical vertebrae consists of Body, transverse process, the foramen transversarium, the vertebral foramen and spinous process The vertebral column (spine), extending from the cranium (skull) to the apex of the coccyx. Vertebral Column-Structure & Functions The vertebral column protects the spinal cord and spinal nerves, supports the weight of the body superior to the level of the pelvis, provides a partly rigid and flexible axis for the body and a pivot for the head, and plays an important role in posture and locomotion. CT CT Significant motion occurs between only the superior 25 vertebrae. The 5 sacral vertebrae are fused in adults to form the sacrum, and the 4 coccygeal vertebrae are fused to form the coccyx. Vertebral Column-Structure & Functions The vertebrae gradually become larger as the vertebral column descends to the sacrum and then become progressively smaller toward the apex of the coccyx. These structural differences are related to the fact that the successive vertebrae bear increasing amounts of the body's weight CT Curvatures of Vertebral Column The vertebral column in adults has four curvatures: cervical, thoracic, lumbar, and sacral The curvatures provide a flexible support (shock-absorbing resilience) for the body. CT The thoracic and sacral curvatures are concave anteriorly, whereas the cervical and lumbar curvatures are concave posteriorly. The thoracic and sacral curvatures are primary curvatures, developing during the fetal period. VERTEBRAL COLUMN C1 & C2 …. Vertebral Column-Structure & Functions Primary curvatures are retained throughout life as a consequence of differences in height between the anterior and the posterior parts of the vertebrae. The cervical and lumbar curvatures are secondary curvatures, which begin to appear in the cervical region during the fetal period but do not become obvious until infancy. CT CT Secondary curvatures are maintained primarily by differences in thickness between the anterior and the posterior parts of the IV discs. The cervical curvature becomes prominent when an infant begins to hold his or her head erect. Vertebral Column-Structure & Functions The lumbar curvature becomes obvious when an infant begins to walk and assumes the upright posture. This curvature, generally more pronounced in females, ends at the lumbosacral angle, formed at the junction of the L5 vertebra with the sacrum. CT CT The sacral curvature of females is reduced so that the coccyx protrudes less into the pelvic outlet. The curvatures provide additional flexibility (shock-absorbing resilience) to the vertebral column, augmenting that provided by the IV discs Structure and Function of Vertebrae Vertebrae vary in size and other characteristics from one region of the vertebral column to another and to a lesser degree within each region. A typical vertebra consists of a vertebral body, vertebral arch, and seven processes. CT The vertebral body gives strength to the vertebral column and supports body weight. The size of vertebral bodies, especially from T4 inferiorly, increases to bear the progressively greater body weight. Vertebral Column-Structure & Functions In life, most of the superior and inferior surfaces of vertebral bodies are covered with hyaline cartilage, which are remnants of the cartilaginous model from which the bone develops, except at the periphery where there is a ring of smooth bone, the epiphysial rim. The cartilaginous remnants permit some diffusion of fluid between the IV disc and capillaries in the vertebral body. CT CT The vertebral arch lies posterior to the vertebral body and is formed by right and left pedicles and laminae. The pedicles are short, stout processes that join the vertebral arch to the vertebral body. The pedicles project posteriorly to meet two broad, flat plates of bone, called laminae, which unite in the midline. The vertebral arch and the posterior surface of the vertebral body form the walls of the vertebral foramen. The succession of vertebral foramina in the articulated column forms the vertebral canal, which contains the spinal cord, meninges (protective membranes), fat, spinal nerve roots, and vessels. CT The indentations formed by the projection of the body and articular processes superior and inferior of the pedicles are vertebral notches The superior and inferior vertebral notches of adjacent vertebrae contribute to the formation of the IV foramina, which give passage to spinal nerve roots and accompanying vessels and contain the spinal ganglia Seven Processes Arise From the Vertebral Arch of a Typical Vertebra One median spinous process projects posteriorly from the vertebral arch Two transverse processes project posterolaterally Four articular processes two superior and two inferior Functions of the Vertebral Column Strong bone protection for the delicate spinal cord The intervertebral foramina one on each side providing access to the spinal cord for spinal nerves, blood vessels and lymph vessels It enables certain amount of movements It support the skull Intervertebral disc acts as shock absorber It forms the axis of the trunk giving attachment to the ribs, shoulder, girdle and upper limbs and pelvic girdle and the lower limb Sacrum and Cocygeal Vertebrae The large, wedge-shaped sacrum in adults is composed of five fused sacral vertebrae. The sacrum provides strength and stability to the pelvis and transmits body weight to the pelvic girdle through the sacroiliac joints. The base of the sacrum is formed by the superior surface of the S1 vertebra. Its superior articular processes articulate

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Tissues CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Tissues using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Four primary tissue types interweave to form the fabric of the body. Describe its general role, the terms would most likely be: Tissues are organized into organs such as the kidneys and the heart. EPITHILIAL TISSUE Epithelia form boundaries between different environments. In its role as an interface tissue, epithelium accomplishes many functions, including CLASSIFICATION OF EPITHELIA They are typically found where absorption and filtration occur and a thin epithelial barrier is desirable. Tissues 1.Squamous cells are flattened and scalelike SIMPLE EPITHELIA The cells of a simple squamous epithelium are flattened laterally, and their cytoplasm is sparse. Simple cuboidal epithelium consists of a single layer of cells as tall as they are wide . Simple columnar epithelium is seen as a single layer of tall, closely packed cells, aligned like soldiers in a row. 1) Dense microvilli on the apical surface of absorptive cells The cells of pseudostratified columnar epithelium vary in height. The short cells are relatively unspecialized and give rise to the taller cells. STRATIFIED EPITHELIA Stratified squamous epithelium is the most widespread of the stratified epithelia. Transitional epithelium forms the lining of hollow urinary organs, which stretch as they fill with urine. CONNECTIVE TISSUE There are four main classes of connective tissue and several subclasses. Its major functions include COMMON CHARACTERISTICS OF CONNECTIVE TISSUE STRUCTURAL ELEMENTS OF CONNECTIVE TISSUE GROUND SUBSTANCE FIBERS Collagen fibers are constructed primarily of the fibrous protein collagen. Elastic fibers are long, thin fibers that form branching networks in the extracellular matrix. Reticular fibers are short, fine, collagenous fibers and are continuous with collagen fibers. CELLS The primary blast cell types by connective tissue class are TYPES OF CONNECTIVE TISSUE CONNECTIVE TISSUE PROPER AREOLAR CONNECTIVE TISSUE ADIPOSE (FAT) TISSUE Adipose tissue is richly vascularized, indicating its high metabolic activity. RETICULAR CONNECTIVE TISSUE DENSE REGULAR CONNECTIVE TISSUE DENSE IRREGULAR CONNECTIVE TISSUE This type of tissue forms sheets in body areas where tension is exerted from many different directions. CARTILAGE It receives its nutrients by diffusion from blood vessels located in the connective tissue membrane surrounding it. Cartilage matrix also contains an exceptional amount of tissue fluid; in fact, cartilage is up to 80% water! There are three varieties of cartilage: HYALINE CARTILAGE Hyaline cartilage provides firm support with some pliability. Most of the embryonic skeleton is formed of hyaline cartilage before bone is formed. ELASTIC CARTILAGE FIBROCARTILAGE BONE (OSSEOUS TISSUE) Osteoblasts produce the organic portion of the matrix; then bone salts are deposited on and between the fibers. BLOOD TISSUES Groups of cells that are similar in structure and perform a common or related function are called tissues. Four primary tissue types interweave to form the fabric of the body. These basic tissues are: 1.Epithelial Tissue 2.Connective Tissue Muscle Tissue 4.Nervous tissue Each has numerous subclasses or varieties. Describe its general role, the terms would most likely be: Covering (epithelial) Support (connective) Movement (muscle) Control (nervous). However, these terms reveal only a fraction of the functions that each tissue performs. Tissues are organized into organs such as the kidneys and the heart. Most organs contain all four tissue types, and their arrangement determines the organ’s structure and capabilities. The study of tissues is called Histology EPITHILIAL TISSUE Epithelial tissue, or an epithelium, is a sheet of cells that covers a body surface or lines a body cavity. Covering and lining epithelium forms the outer layer of the skin, dips into and lines the open cavities of the cardiovascular, digestive, and respiratory systems, and covers the walls and organs of the closed ventral body cavity. Epithelia form boundaries between different environments. For example, the epidermis of the skin lies between the inside and the outside of the body, and epithelium lining the urinary bladder separates underlying cells of the bladder wall from urine. Nearly all substances received or given off by the body must pass through an epithelium In its role as an interface tissue, epithelium accomplishes many functions, including 1.Protection 2.Absorption Filtration Excretion 5.Secretion Sensory reception CLASSIFICATION OF EPITHELIA Each epithelium is given two names. The first name indicates the number of cell layers present; the second describes the shape of its cells. Based on the number of cell layers, there are simple and stratified epithelia. Simple epithelia are composed of a single cell layer. They are typically found where absorption and filtration occur and a thin epithelial barrier is desirable. Stratified epithelia, consisting of two or more cell layers stacked one on top of the other, are common in high-abrasion areas where protection is important, such as the skin surface and the lining of the mouth. Tissues In cross section, all epithelial cells have six sides, and an apical surface view of an epithelial sheet looks like a honeycomb. This polyhedral shape allows the cells to be closely packed. However, epithelial cells vary in height, and on that basis, there are three common shapes of epithelial cells. 1.Squamous cells are flattened and scalelike 2.Cuboidal cells are boxlike, approximately astall as they are wide. Columnar cells are tall and column shaped. In each case, the shape of the nucleus conforms to that of the cell. Tissues The nucleus of a squamous cell is a flattened disc; that of a cuboidal cell is spherical; and a columnar cell nucleus is elongated from top to bottom and usually located close to the cell base. SIMPLE EPITHELIA The simple epithelia are most concerned with absorption, secretion, and filtration. Because they consist of a single cell layer and are usually very thin, protection is not one of their specialties The cells of a simple squamous epithelium are flattened laterally, and their cytoplasm is sparse. In a surface view, the close-fitting cells resemble a tiled floor. Tissues Thin and often permeable, this epithelium is found where filtration or

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Thoracic Cage-Structure & Functions CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Thoracic Cage-Structure & Functions using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic COMPONENTS OF THORACIC CAGE: Thoracic Cage Sternum/Breast bone PARTS OF STERNUM: Ribs Typical ribs: 1 – 7 pairs of ribs are attached anteriorly to the sternum by their costal cartilages. Typical Ribs (2 -7) Atypical Rib (1st Rib) JOINTS OF STERNUM JOINTS OF RIBS MOVEMENTS COMPONENTS OF THORACIC CAGE: Sternum Manubrium, Body (Gladiolus), Xiphoid process Ribs 7 True Ribs 5 False Ribs (including 2 floating ribs) Clavicle Scapula Pectoral girdle 12 Thoracic Vertebrae (T1 – T12) Thoracic Cage It forms a conical enclosure for the lungs and heart and provides attachment for the pectoral girdle and upper limb. It has a broad base and a narrower superior apex; it is rhythmically expanded by the respiratory muscles to create a vacuum that draws air into the lungs. The inferior border of the thoracic cage is formed by a downward arc of the ribs called the costal margin. The ribs protect the thoracic organs and spleen, most of the liver, and to some extent the kidneys. Sternum/Breast bone Flat bone, with 3 parts: Manubrium sterni Body/Gladiolus Xiphoid process PARTS OF STERNUM: Manubrium sterni Jugular/suprasternal notch Articulates with Clavicles and Ribs 1 and 2 Lies opposite to T3 and T4 vertebrae Manubriosternal joint inferiorly – called Sternal Angle/Angle of Louis – opposite articulation with 2nd rib – at the level of intervertbral disc between T4 and T5 vertebrae (imp. for counting the ribs) PARTS OF STERNUM: Body/Gladiolus Articulates with Ribs 2-7 Xiphisternal joint inferiorly- opposite to T9 vertebra Xiphoid process Cartilaginous – calcifies through time Allows attachment of muscles Tip of xiphoid – at level of T10 Sternocostal joints Ribs Typical Ribs 2-7 Head Neck Tubercle Angle Shaft Subcostal groove Atypical Ribs 1, 8 -10 Rib 1 – short, flat and supports Subclavian vessels Ribs 1, 10-12 – articulate with only 1 vertebra Ribs 11 and 12 – “floating ribs” – do not articulate with Transverse processes of Vertebrae or Sternum Typical ribs: 1 – 7 pairs of ribs are attached anteriorly to the sternum by their costal cartilages. Atypical ribs: 8th, 9th and 10th pairs of ribs are attached anteriorly to each other and to the 7th rib by means of their costal cartilages and small synovial joints. Floating ribs :The 11th and 12th pairs have no anterior attachment. They are embedded in the abdominal muscles. Typical Ribs (2 -7) Long, twisted, flat bone The anterior end of each rib is attached to the corresponding costal cartilage A rib has a head, neck, tubercle, shaft, and angle Head – located posteriorly – has 2 facets for articulation – one for the numerically corresponding vertebral body and the other for the vertebral body immediately above it. Neck is a constricted portion – between the head and the tubercle. The Tubercle is a prominence on outer surface of the rib – at the junction of the neck with the shaft. It has a facet for articulation with the transverse process of the numerically corresponding vertebra. The Shaft is thin, flat and twisted on its long axis. It has a rounded, smooth superior border and a sharp, thin inferior border which has costal groove (it accommodates the intercostal vessels and nerve (VAN ) The angle is where the shaft of the rib bends sharply forward. Atypical Rib (1st Rib) The first rib has a close relationship to the lower nerves of the Brachial plexus, Subclavian artery and vein This rib is small and flattened from above downward Scalenus anterior muscle is attached to its upper surface and inner border Anterior to the attachment of Scalenus anterior, the Subclavian vein crosses the rib Posterior to the attachment of Scalenus anterior, the Subclavian artery and the lower trunk of the Brachial plexus cross the rib and lie in contact with the bone JOINTS OF STERNUM MANUBRIOSTERNAL JOINT: cartilaginous joint, symphysis between Manubrium and body of Sternum XIPHISTERNAL JOINT cartilaginous joint between Xiphoid process and body of Sternum The Xiphoid process usually fuses with the body of the Sternum during middle age JOINTS OF RIBS COSTOVERTEBRAL JOINTS: 2 joints between heads of the Ribs and bodies of Vertebrae (corresponding and upper)- Synovial joints 1st, 10th, 11th and 12th rib has 1 synovial joint with the corresponding vertebra, the rest have 2 each; one for the corresponding vertebra and the other for the vertebra above it 1 joint between tubercle of Ribs and transverse process of Vertebra (corresponding) – Synovial joint (1st- 10th Rib) Intra articular ligament connects head of Rib to the intervertebral disc JOINTS OF RIBS COSTOCHONDRAL JOINTS: Joints of the Ribs with costal cartilages Cartilaginous joints STERNOCOSTAL JOINTS: Joints between Sternum and costal cartilages 1st : Cartilaginous joint 2nd – 10th : Synovial joints= 2nd-7th costal cartilages with Sternum 8th-10th costal cartilages with each other (11th and 12th costal cartilages are embedded in muscles) MOVEMENTS Cartilaginous joints are immobile (thus 1st rib and all costochondral joints do not move during respiration) Synovial joints are slightly mobile (due to movements in both the joints between head, tubercle and vertebrae, necks of Ribs rotate along their axis, helping in raising and lowering of ribs during respiration) ← 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 The Cell: Structure and Functions CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study The Cell: Structure and Functions using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic It’s the basic, structural and functional unit of life Cell structure The cell membrane The Cell: Structure and Functions Proteins in the cell membrane They act as pores for passage of ions Transport across the cell membrane Passive diffusion Facilitated diffusion Active transport Bulk transport Nucleus Nucleoli Endoplasmic reticulum Golgi apparatus Mitochondria Lysosomes The cell cycle Interphase Dividing phase: MITOSIS Anaphase: sister chromatids continue moving towards opposite poles Importance of cell division Meiosis The cell It’s the basic, structural and functional unit of life Each cell is capable of performing all the essential life functions. The process by which cells assume specialized functions and structure is known as differentiation. Cell structure Cells conform to the same basic structure. All cells are composed of an external lining membrane known as the plasma membrane that serves as an interface between the internal and external environment. The cell membrane surrounds a number of organelles that are embedded in a fluid medium known as the cytoplasm. The cell membrane All cell membranes conform to the same basic model: the fluid mosaic model. The model was proposed by Singer and Nicholoson in 1970. The cell membrane Cell membrane The Cell: Structure and Functions The cell membrane is made up of a lipid by layer with a hydrophilic polar end and a hydrophobic non polar end. The hydrophilic end is made up of glycerol attached to a nitrogenous compound by a phosphate bond. The nitrogenous cpds include chlorine, ethanolamine or serine. They are positively charged. The phosphate gp is negatively charged. The Cell: Structure and Functions The non polar end is made up of two chains of fatty acids, one of them is straight and saturated while the other is kinked and non saturated. The kinked fatty acids increase flexibility and fluidity Between the fatty acids is cholesterol molecules in the ratio of 1:1 with the phospholipids. The cholesterol prevents close packing and increases fluidity. They regulate the fluidity and increase stability of the cell membrane. Proteins in the cell membrane Associated with the cell membrane are three types of proteins: extrinsic, intrinsic and transmembrane proteins. These make up ½ the total mass of the cell membrane. Extrinsic proteins are found on the outside surface, intrinsic on the internal surface of the cell membrane while transmembrane proteins traverse the whole thickness of the cell membrane They act as pores for passage of ions Associated with the proteins and phospholipids are carbohydrates forming glycoproteins and glycolipids. These are involved in cell recognition, formation of intracellular adhesions and absorption of molecules to the cell surface. Transport across the cell membrane Molecules enter and leave Passive diffusion Facilitated diffusion Active transport Bulk transport Passive diffusion Requires a concentration gradient. Doesn’t involve metabolic energy. Molecules move from a region of high concentration gradient to a region of low concentration gradient across a semi permeable membrane It is for non polar molecules like ethanol, and polar molecules that are uncharged like oxygen, carbondioxide, urea Facilitated diffusion Similar to simple diffusion but requies a carrier protein It is for larger hydrophillic molecules like amino acids, glucose and fatty acids The binding to carriers is specific but reverscible Active transport Active transport Requires energy in form of ATP Occurs against a concentration gradient It involves pumps Bulk transport Includes endocytosis and exocytosis (phagocytosis and pinocytosis) Cell organelles: Nucleus Nucleus Largest of all cell organelles. Has a nuclear membrane that has pores Contains the genetic material of the cell inform of DNA and proteins(nucleoproteins). The proteins include the DNA associated proteins: histones, and the non DNA associated proteins. Nucleoli Densely stained structures found inside the nucleus. They are sites for ribosomal RNA synthesis. Endoplasmic reticulum Rough endoplasmic reticulum Made up of interconnecting network of tubules, sacs and vesicles covered by ribosomes Sites for synthesis and packaging of proteins Smooth endoplasmic reticulum: not covered by ribosomes. Sites for lipid synthesis, and synthesis of cell membrane. Golgi apparatus Consists of s system of stacked, saucer shaped cisternae with the concave surface facing the nucleus Involved in intracellular transport by packaging proteins into vesicles and releasing them by exocytosis. Golgi apparatus Mitochondria Mitochondria Cigar shaped highly motile organelles composed of a smooth outer membrane and a folded inner membrane (cristae) Sites for energy production in the cell Tend to be plenty in highly metabolic tissues like liver and muscle cells. Lysosomes Lysosomes Oval membrane bound organelles with numerous enzymes involved in breakdown of phagocytosed bacteria and other particles. The cell cycle Refers to events that occur in a cell’s lifetime The cycle is composed of a dividing phase (M phase) and a non dividing phase (Inter phase) There are three types of cells according to the cell cylcle: the continuously dividing cells that are always dividing e.g skin cells and cells of digestive system The Cell: Structure and Functions The facultative dividers: these live the cell cycle and enter the Go phase but retain the ability to divide e.g liver cells The terminally differentiated cells: leave the cell cycle permanently and lose the ability to divide e.g cells of the nervous system The cell cycle Interphase Composed of G1, S and G2 phases G1 phase: cells perform their functions S phase: cells replicate their DNA G2 phase: cells prepare for division. Dividing phase: MITOSIS Composed of prophase, metaphase, anaphase and telophase Prophase: chromosomes become visible, initially thread like, but later appear to be composed of two sister chromatids joined at centromere, nucleoli disappears, process ends with disappearence of nuclear membrane The Cell: Structure and Functions Metaphase: chromosomes arrange themselves at equator of the spindle, microtubules span from opposite centrioles, sister chromatids begin separating and moving towards opposite poles Anaphase: sister chromatids continue moving towards opposite poles Telophase: sister

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Terminology CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Terminology using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic Terminology Word Part #1 Word Quiz #2 Word Part #3 Word Part #4 Word Part #5 Word Part #6 Word Part #7 Word Part #8 Word Part #9 Word Part #10 Word Part #11 Word Part #12 Word Part #13 Word Part #14 Singular Plural Terminology Human Anatomy & Physiology: Latin and Greek Word-Part List (prefixes, suffixes, roots) Students of any biology course should learn to recognize the meaning of word parts as they often give clues to the meaning of a scientific term, function, or process. Science terminology is predominately based in the Latin and Greek languages. The following list of prefixes, suffixes, and roots will be used in this and most Biology (bio = life, logy = study of) courses. To help with pronunciation, word parts need to be linked together. The linkage for many word parts is “o”. For example, linking the root “cardi” with the suffix “-pathy” would make the word difficult to pronounce; therefore an “o” is used to link the root with the suffix. The completed word is written “cardiopathy” and pronounced kar-deop-ah-the (heart disease). Accurate spelling of each work is also important. Changing one letter may change the word part and its meaning. Examples include: “ileum” is a part of the small intestine & “ilium” is a bone in the hips, “ped” refers to the foot & “pedia” refers to children, “ab” means away & “ad” means toward. Finding a word in a dictionary, glossary, or index requires a knowledge of spelling – at least the beginning of a word. For example, pneumonia and psychology have a silent “p”. By the end of this course you should be able to: (1) Understand the importance of medical terminology and how it can be incorporated into the study of the human body, (2) Differentiate between a prefix, suffix, word root, and a compound term, (3) Link word parts to form medical terms, (4) Differentiate between singular and plural endings of medical terms, (5) Dissect (cut) compound medical terms into parts to analyze their meaning, and (6) Recognize and pronounce commonly used prefixes, suffixes, and root words used in medical terminology. The last page of this “Word Part” packet has a list of singular and plurals word forms. Word Part #1 Word Part Meaning Example(s) Meaning of Example(s) a-, an, non Without, Not Apnea, Anuria, Nonstriated Not breathing, Without urine, Muscle not striated ab-, ef- Away Abductor muscle, Efferent Neuron Muscle pulling away from midline (deltoid), Carrying info away from brain ad-, af- Toward Afferent neuron, Adductor muscle Carry info toward brain, Muscle pulling toward midline (groin) adi-, lip(o)- Fat Adipose, Liposuction Fat tissue, Removing (by suction) fat from the body -alg Pain Neuralgia, Fibromyalgia Nerve pain, Muscle pain ana- Up Anabolic reaction Building up molecules (bonding amino acids together to make proteins) ang(i)- Vessel Angiogenesis, Vasodialator Making of a new blood vessel, Medicines that widen a vessel ante-, pre-, pro- Before Prenatal, Antebrachial, Promonocyte Before birth, Before the upper arm, Before the monocyte is mature anti-, contra- Against, Resisting Antibody, Contraception Resisting a foreign body (pathogen), Against conception (egg + sperm) aqua(e)-, hydr Water Aqueous, hydrocephalus Water solution, Water (cerebral spinal fluid – CSF) on the brain arthr(o), artic- Joint Arthritis, Articulation Joint inflammation, Joint (where two bones meet) -ase Enzyme Maltase, Lipase Enzyme breaking down maltose, Enzyme breaking down lipids/fats audi- Hear Auditory nerve Nerve connecting the ear to the brain aut(o)- Self Autoimmunity Self-immunity (when a persons antibodies attack its own cells/tissues) bi-, di-, diplo- Two Bicuspid, Diencephalon, Diplococcus 2 pointed (tooth or heart valve), 2 parts within the brain, 2 round bacteria brachy-, brev(i)- Short Brachydactyly, Fibularis brevis Short digits (toes or fingers), Short muscle in the lower leg brady- Slow Bradycardia Slower than normal heart rate bronch- Airway Bronchitis Airway (bronchus – tube entering lungs) inflammationcard- Heart Cardiology Study of the heart cat- Down Catabolic reaction Breaking down molecules (protein bonds being broken to form amino acids) Word Quiz #2 Word Part Meaning Example(s) Meaning of Example(s) cent- 100, 100th Century, Centigram 100 years, 1/100th of a gram -centesis Puncture Amniocentesis Puncture to aspirate (remove) amniotic fluid from amniotic sac cephal-, -ceps Head Hydrocephalus, Biceps femoris Water in brain (in the head), 2-headed (2 tendons) muscle by femur chol-, cystic Gallbladder Cholecystokinin, Cystic duct Hormone causing gallbladder contraction, Tube (for bile) from gallbladder chondr- Cartilage Chrondrocyte Cartilage cell -cide Kill Spermacide Sperm killer circ-, peri- Around Circumcision, Periodontal Cut around (ex. male foreskin), Around the teeth -clast Break, Destroy Osteoclast Bone breaker (cells that destroy cells, thus shaping a bone) co-, con-, sym-, syn-, sys- Together, With Congenital, Synthesis, System Born with, Put together, Organs working together coel-, sinu- Cavity, Space Coelom, Frontal sinus Body cavity, Space in the frontal bone Word Part #3 Word Part Meaning Example(s) Meaning of Example(s) corp-, soma- Body Corpus luteum, Somatic cell Yellow body (former follicle in ovary), Body cell (all non-sex cells) -crine Secrete, Release Endocrine gland Glands that secrete hormones into the bloodstream cut, derm Skin Subcutaneous, Dermatitis Below the skin, Skin inflammation cyan- Blue Cyanosis Condition causing skin to turn blue (due to low oxygen levels) -cyte Cell Leukocyte White blood cell dactyl, digit Finger or Toe Syndactyly Fingers or Toes that are together (webbed) dec(k) 10, 1/10th Decade, Dekagram, Deciliter 10 years, 10 grams, 1/10th of a liter dent, dont Tooth/Teeth Dentalgia, Orthodontist Tooth pain, Doctor that straightens teeth dia-, per-, trans- Through, Separate, Across Diarrhea, Permaeable, Transcutaneous Flow through (intestines), Across a membrane, Across skin dys-, mal- Bad, Painful, Difficult Dyspnea, Malnutrition, Malabsorption Difficult breathing, Bad nutrition/diet, Poor nutrient absorption Word Part #4 Word Part Meaning Example(s) Meaning of Example(s) -ectomy, -tom, -sect Cut, Cut out Appendectomy, Lobotomy, Dissect Cut out appendix, Cut out cerebral (brain) lobe, Cut in

DIAGNOSTIC RADIOGRAPHY · NTA LEVEL 4 · SEMESTER ONE Structure And Functions Of Urinary System CRT04101 · Anatomy, Physiology and Pathology START READING NOTES Study Structure And Functions Of Urinary System using the sections below. Use the topic navigation to continue through Anatomy, Physiology and Pathology. Contents of This Topic By the end of this session students are expected to be able to: Definition of the Urinary System Structure And Functions Of Urinary System Structures of the Urinary System The renal medulla consists of 6-18 distinct conical or triangular or wedge-shaped structures called renal pyramids. Renal corpuscle The renal tubule Blood flow and urine formation Accessory organ of the urinary system Urinary bladder Urethra Functions of the Structures of the Urinary System 2. Regulation of blood pressure 6. Synthesis of Vitamin D; In form urine Key Points Functions of the Ureter are: Evaluation Structure and Functions of the Urinary System By the end of this session students are expected to be able to: Define the Urinary System List Structures of Urinary System Describe the Structures of the Urinary System Explain the Functions of the Structures of the Urinary System Definition of the Urinary System What is urinary system? What are the structures of urinary system? Structure And Functions Of Urinary System Urinary system: is the system which regulates the content of blood plasma to maintain the homeostasis of the internal fluid environment within normal limits (control the composition of blood and blood volume) It removes waste products from the blood, of which many of them are toxic The principal organ of the urinary system is the kidney The accessory organs include the ureters, urinary bladder and urethra The following are the (4) structures of the urinary system: Kidneys Ureters Urinary bladder, Urethra Structures of the Urinary System The kidneys Are bean shaped organs with a medial indentation located in the upper abdominal cavity on either side of the vertebral column, behind the peritoneum.They typically extend from T12 to L3.The right kidney is slightly lower than the left due to presence of the liver. Are embedded in adipose tissue that acts as a cushion and is in turn covered by a fibrous connective tissue membrane called the renal fascia, which helps hold the kidneys in place The renal artery enters the kidney, and the renal vein and ureter emerge The outer tissue layer is called the renal cortex, which is made of renal corpuscles and convoluted tubules The inner tissue layer is the renal medulla, which is made of loops of henle and collecting tubules The renal medulla consists of 6-18 distinct conical or triangular or wedge-shaped structures called renal pyramids. The tip of each pyramid is its apex or papilla Renal pelvis is a cavity formed by the expansion of the ureter within the kidney at the hilus Funnel shaped extensions of the renal pelvis; called calyces enclose the papillae of the renal pyramids Urine flows from the renal pyramids into the calyces, then to the renal pelvis and out into the ureter Nephron Nephron is the structure and functional unit of the kidney It is well associated with the blood vessels and the urine is formed there Each nephron has two major portions: a renal corpuscle and a renal tubule NEPHRON Renal corpuscle Consists of a glomerulus surrounded by a Bowman‘s capsule. The glomerulus is a capillary network that arises from an afferent arteriole and empties into an efferent arteriole. The diameter of the efferent arteriole is smaller than that of the afferent arteriole, which helps maintain a fairly high blood pressure in the glomerulus. Bowman’s capsule Is the expanded end of a renal tubule and encloses the glomerulus. The fluid that is formed from the blood in the glomerulus will eventually become the urine The renal tubule Continues from Bowman‘s capsule and consists of the proximal convoluted tubule (in the renal cortex), loop of Henle (in the renal medulla), and distal convoluted tubule (in the renal cortex). The distal convoluted tubules from several nephrons empty into a collecting tubule. Several collecting tubules then unite to form a papillary duct that empties urine into a calyx of the renal pelvis. Blood flow and urine formation Blood enters the kidney through the renal artery and flows downstream to afferent arterioles and emerge through efferent arterioles, flowing to upper stream to renal veins, and finally to inferior vena cava The formation of urine involves three major processes The first is glomerular filtration, which take place in the renal corpuscles and The second and third are tubular reabsorption and tubular secretion, which take place in the renal tubules. Accessory organ of the urinary system Accessory organs of the urinary system are; The ureters, urinary bladder, and urethra are responsible for the periodic elimination of urine and do not change the composition or amount of urine. Ureter Each ureter extends from the hilus of a kidney to the lower, posterior side of the urinary bladder The smooth muscle in the wall of the ureter contracts in peristaltic waves to propel urine toward the urinary bladder. As the bladder fills, it expands and compresses the lower ends of the ureters to prevent backflow of urine. Urinary bladder It is a muscular sac below the peritoneum and behind the pubic bones. In women, the bladder is inferior to the uterus; in men, the bladder is superior to the prostate gland. The bladder is a reservoir for accumulating urine, and it contracts to eliminate urine. The mucosa of the bladder is transitional epithelium, which permits expansion without tearing the lining. The bladder wall is lined with smooth muscle called detrusor, which helps contractions When the bladder is empty, the mucosa appears wrinkled. Urethra Carries urine from the bladder to the exterior In women, the urethra is 1 to 1.5 inches long and is anterior to the vagina In men it is 7 to 8 inches, the first part being surrounded by prostate gland and the second passes through the cavernous tissue of the penis Functions