Introduction to Human Anatomy PDF

Lau Human anatomy By Gutu B (Anatomist) 4/10/2023 1  INTRODUCTION TO HUMAN ANATOMY 4/10/2023 2  What is Anatomy? Anatomy : is a science that studies structure o...

Lau Human anatomy By Gutu B (Anatomist) 4/10/2023 1  INTRODUCTION TO HUMAN ANATOMY 4/10/2023 2  What is Anatomy? Anatomy : is a science that studies structure of the body The word anatomy is derived from Greek word anatome = up (ana) + cutting (tome) means  “to cut up” or  “to cut open.” The art of separating the parts of an organism in order to ascertain their position, relations & structures. 4/10/2023 3  SUBDIVISIONS OF ANATOMY Gross/ Cadaveric Anatomy Microscopic Anatomy (Histology) Developmental Anatomy (Embryology) Clinical Anatomy (Applied) Surface (Topographic) Anatomy Radiographic Anatomy Pathological Anatomy Sectional Anatomy 4/10/2023 4  Sectional anatomy Internal structure and relationships of the body through the use of sections Surface anatomy: Surface markings of the body to understand the relations of deep or internal anatomy through visualization and palpation (gentle touch) Radiographic anatomy: Body structures that can be visualized with imaging like x-rays Pathological anatomy Structural changes associated with disease 4/10/2023 5  Levels of Structural Organization Chemical – atoms combined to form molecules Cellular – cells are made of molecules Tissue – consists of similar types of cells Organ – made up of different types of tissues Organ system – consists of different organs that work closely together Organismal – made up of the organ systems 4/10/2023 6  Levels of Organization 4/10/2023 7 4/10/2023 8  Anatomical approach Anatomy can be studied following either  regional approach  systemic approach  clinical approach 4/10/2023 9  1. Body Regions(Regional anat.) Regional anatomy (topographical anatomy) considers the organization of the human body as major parts or segments The human body is partitioned into two main regions, called the axial and appendicular regions. The axial region includes the head, neck, and trunk which comprise the main vertical axis of our body Our limbs, or appendages, attach to the body’s axis and make up 4/10/2023 10 the appendicular region 4/10/2023FIGURE 1. Major parts of the body and regions of the lower limb. Anatomy is described relative 11 to the anatomical position illustrated here.  2. Systemic Approach 4/10/2023 12  Systemic Anatomy… Is the study of the body’s organ systems that work together to carry out complex functions. The body is divided into 11 body systems. 4/10/2023 13  Integumentary Components Skin Hair, nails Function Provides protection Regulates body temperature Site of cutaneous receptors Synthesizes vitamin D Prevents water loss 4/10/2023 1-14  Skeletal Components Bones Joints and adjacent cartilages Function Provides support and protection Site of hematopoeisis (blood cell production) Stores calcium and phosphorus Allows for body movement 4/10/2023 15  Muscular Components Skeletal Muscles Associated Connective Tissues (tendons) Function Produces body movement Generates heat when muscles contract 4/10/2023 16  Nervous Components Brain, Spinal cord (CNS) Nerves (PNS), sense receptors A regulatory system that controls body movement Responds to sensory stimuli Helps control all other systems of the body Also responsible for consciousness, intelligence, memory 4/10/2023 17  Endocrine Components Glands that secrete hormones E.g. :Pituitary, pancreas, thyroid Consists of glands and cell clusters that secrete hormones, some of which regulate body and cellular growth chemical levels in the body reproductive functions 4/10/2023 18  Cardiovascular Consists of a pump (the heart) that moves blood through blood vessels in order to distribute hormones, nutrients, gases, and pick up waste products 4/10/2023 19  Lymphatic Components Lymphatic Organs (spleen, lymph nodes, thymus, etc.) Lymphatic Vessels Transports and filters lymph (interstitial fluid) Initiates an immune response when necessary 4/10/2023 20  Immune System Components Immune Organs (red bone marrow, thymus, etc.) White blood cells (lymphocytes, macrophages, etc.) Function Defense (Immune 4/10/2023 response) 21  Respiratory Components Lungs Tubing ( trachea, bronchus, etc.) Larynx (vocal cords) Responsible for exchange of gases (oxygen and carbon dioxide) between blood and the air in the lungs 4/10/2023 22  Digestive Components Alimentary canal (mouth, pharynx, esophagus, stomach, small intestine, large intestine) Accessory structures(liver, salivary glands, etc.) Function Mechanically and chemically digests food materials Absorbs nutrients Expels waste products 4/10/2023 23  Urinary Components Kidneys, Ureters, Urinary bladder, Urethra Filters the blood and removes waste products from the blood Concentrates waste products in the form of urine, and expels urine from the body 4/10/2023 24  Male Reproductive System Produces male sex cells (sperm) and male hormones (e.g., testosterone) Transfers sperm to the female 4/10/2023 25  Female Reproductive System Produces female sex cells (oocytes) and female hormones (e.g., estrogen and progesterone) Receives sperm from male Site of fertilization of oocyte Site of growth and development of embryo and fetus 4/10/2023 26  Approach …… 3. Clinical anatomy (applied anatomy) Emphasizes aspects of bodily structure and function important in the practice of medicine, dentistry, and the allied health sciences. It incorporates the regional and systemic approaches to studying anatomy and stresses clinical application. 4/10/2023 27  lo g y in o Term ica l t o m An a 4/10/2023 28  Cont.… Anatomical terminology introduces and makes up a large part of medical terminology. Although you are familiar with common, colloquial terms for parts and regions of the body, you must learn the international anatomical terminology (e.g., axillary fossa instead of armpit and clavicle instead of collarbone) That enables precise communication among healthcare professionals and scientists worldwide. Without anatomic terms, one cannot accurately discuss or record the abnormal functions of joints, the actions of muscles, the alteration of position of organs, or the exact location of swellings29or tumors. 4/10/2023  1. Anatomical position The standard position anatomists used to describe the location of the body regions and parts. Is described as the body facing you ,stand erect feet placed together and flat on the floor. arms straight by the side with palms facing forward. All references to the body are made as if the body is in this position. 4/10/2023 30  Anatomical Position Body erect Feet slightly apart Palms facing forward Thumbs point away from body 4/10/2023 31 Figure 1.7a  2.Anatomical Planes A plane is an imaginary surface that slices the body into specific sections. The three major anatomic planes of reference are the coronal, transverse, and sagittal planes. 4/10/2023 32  Sections and Planes A coronal plane, also called a frontal plane, is a vertical plane that divides the body into anterior (front) and posterior (back) parts. 4/10/2023 33  Sections and Planes A transverse plane, also called a cross-sectional plane or horizontal plane, cuts perpendicularly along the long axis of the body or organ separating it into both superior (upper) and inferior (lower) parts. 4/10/2023 34  Sections and Planes A sagittal plane or median plane, extends through the body or organ vertically and divides the structure into right and left halves. 4/10/2023 35  Sections and Planes A sagittal plane in the body midline is a midsagittal plane. A plane that is parallel to the midsagittal plane, but either to the left or the right of it, is termed a parasagittal (or sagittal) plane. A minor plane, called the oblique plane, passes through the specimen at an angle. 4/10/2023 36 4/10/2023 37  Body Planes Figure 1.8 4/10/2023 38  ABDOMINOPELVIC REGIONS AND QUADRANTS To describe the location of the many abdominal and pelvic organs more easily there two methods of dividing the abdominopelvic cavity into smaller areas. 1. Two transverse and two vertical lines partition this cavity into nine abdominopelvic regions top horizontal line:- the subcostal line is drawn just inferior to the right and left lateral margins of the rib cage; 4/10/2023 39  the bottom horizontal line: trans tubercular line intersects the iliac tubercles, landmarks near the top of the right and left hip bones. vertical lines:- the left and right midclavicular lines are drawn through the midpoints of the clavicles just medial to the nipples. quad-one-fourth method: is simpler and divides the abdominopelvic cavity into quadrants In this method:- a transverse line, the trans umbilical line, a midsagittal line, the median line, are passed through the umbilicus 4/10/2023 40  Abdominopelvic Regions The abdominopelvic cavity is partitioned into 9 smaller, imaginary compartments. 4/10/2023 41 4/10/2023 42 4/10/2023 43  Descriptive anatomic terms Terms related to position Terms related to movement 4/10/2023 44  Term Meaning Usage Superior (cranial) Nearer to head Heart is superior to stomach Inferior (caudal) Nearer to feet Stomach is inferior to heart Anterior (ventral) Nearer to front Sternum is anterior to heart Posterior (dorsal) Nearer to back Kidneys are posterior to intestine Medial Nearer to Fifth digit (little finger) is on median plane medial side of hand Lateral Farther from First digit (thumb) is on median plane lateral side of hand 4/10/2023 45  Proximal Nearer to trunk or Elbow is proximal point of origin to wrist; proximal part of (e.g., of a limb) artery is its beginning Distal Farther from trunk Wrist is distal to elbow; or point of origin distal part of lower limb is foot (e.g., of a limb) Superficial Nearer to or Muscles of arm are superficial on surface to its bone (humerus) Deep Farther from surface Humerus is deep to arm muscles Dorsum Dorsal surface of Veins are visible in dorsum of hand hand or foot Palm Palmar surface Skin creases are visible on palm of hand Sole Plantar surface Skin is thick on sole of foot of foot 4/10/2023 46 4/10/2023 47  Inferomedial :- means nearer to the feet and closer to the median plane. for example, the anterior parts of the ribs run inferomedially. Superolateral :- means nearer to the head and farther from the median plane. Dorsum :- refers to the 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. The sole:- indicates the inferior aspect or bottom of the foot. much of which is in contact with the ground when standing barefoot. The palm:- refers to the flat of the hand, excluding the five digits, is the opposite of the dorsum of the hand. 4/10/2023 48  Terms of Laterality:- Paired (bilateral) structures:- having right and left members e.g., the kidneys are bilateral, Unilateral :- structures occurring on one side only (e.g., the spleen) Ipsilateral :- occurring on the same side of the body; the right thumb and right great toe are ipsilateral. Contralateral :- occurring on the opposite side of the body; the right hand is contralateral to the left foot. 4/10/2023 49  Terms of Movement:- Movements taking place at joints are described relative to the axes around which the part of the body moves and the plane in which the movement takes place. Terms of Movement:- Extension: Increase angle of joint Flexion: decrease angle of joint 4/10/2023 50 4/10/2023 51  Abduction :- moving away from the median plane of the body in the frontal plane. Adduction :- moving toward the median plane of the body in the frontal (coronal) plane. When referring to the digits (fingers and toes): abduction means spreading them, and adduction means drawing them together. Rotation :- moving a part of the body around its long axis. Medial rotation turns the anterior surface medially, and lateral rotation turns this surface laterally. Circumduction :- is the circular movement of the limbs, or parts of them, combining in sequence the movements of flexion, extension, abduction, and adduction. 4/10/2023 52 4/10/2023 53  Pronation :- is a medial rotation of the forearm and hand so that the palm faces posteriorly. Supination :- is a lateral rotation of the forearm and hand so that the palm faces anteriorly, as in the anatomical position. Eversion :- turning the sole of foot outward. Inversion :- turning the sole of foot inward. Elevation :- raises or moves a part superiorly. Depression :- lowers or moves a part inferiorly. 4/10/2023 54  Inversion-eversion 4/10/2023 55  Movement con’d 4/10/2023 56  Cont. Protrusion is a movement anteriorly (forward) as in protruding the mandible (chin), lips, or tongue. Retrusion is a movement posteriorly (backward). Opposition is the movement by which the pad of the 1st digit (thumb) is brought to another digit pad. Reposition describes the movement of the 1st digit from the position of opposition back to its 4/10/2023 anatomical position 57  Bone markings Bone markings appear wherever tendons, ligaments, and fascias are attached or where arteries lie adjacent to or enter bones Some of the various markings and features of bones are: Capitulum: small, round, articular head (e.g., capitulum of the humerus). Condyle: rounded, knuckle-like articular area, often occurring in pairs (e.g., the lateral and medial femoral condyles). Crest: ridge of bone (e.g., the iliac crest). Epicondyle: eminence superior or adjacent to a condyle (e.g., lateral epicondyle of the humerus). Facet: smooth flat area, usually covered with cartilage, where a bone articulates with another bone (e.g., superior costal facet on the body of a vertebra for articulation with a rib).  Bone markings Foramen: passage through a bone (e.g., obturator foramen). Fossa: hollow or depressed area (e.g., infraspinous fossa of the scapula). Groove: elongated depression or furrow (e.g., radial groove of the humerus). Head (L. caput): large, round articular end (e.g., head of the humerus). Line: linear elevation (e.g., soleal line of the tibia). Malleolus: rounded process (e.g., lateral malleolus of the fibula). Notch: indentation at the edge of a bone (e.g., greater sciatic notch).  Bone markings and formations Protuberance: projection of bone (e.g., external occipital protuberance). Spine: thorn-like process (e.g., the spine of the scapula). Spinous process: projecting spine-like part (e.g., spinous process of a vertebra). Trochanter: large blunt elevation (e.g., greater trochanter of the femur). Trochlea: spool-like articular process or process that acts as a pulley (e.g., trochlea of the humerus). Tubercle: small raised eminence (e.g., greater tubercle of the humerus). Tuberosity: large rounded elevation (e.g., ischial tuberosity). FIGURE 12. Bone markings and formations. Markings appear on bones wherever tendons, ligaments, and fascia attach. Other formations relate to joints, the passage of tendons, and the provision of increased leverage.  Joints Joints (articulations) are unions or junctions between two or more bones or rigid parts of the skeleton.  CLASSIFICATION OF JOINTS  Three classes of joints are described 1. Synovial Joints 2. Fibrous Joints 3. Cartilaginous Joints FIGURE 16. The three classes of joints  1. Synovial Joints are the most common type Freely moveable joints are united by a joint capsule spanning and enclosing a joint cavity The joint cavity of a synovial joint, like the knee, is a potential space that contains a small amount of lubricating synovial fluid, secreted by the synovial membrane Provide free movement between the bones they join They are joints of locomotion, typical of nearly all limb joints Can be classified into six major types as plane, hinge, saddle,  Synovial Joints 1. Plane joints permit gliding or sliding movements in the plane of the articular surfaces. The opposed surfaces of the bones are flat or almost flat, with movement limited by their tight joint capsules. Plane joints are numerous and are nearly always small. An example is the acromioclavicular joint between the acromion of the scapula and the clavicle  Synovial Joints 2. Hinge joints Permit flexion and extension only Permit movements that occur in one plane (sagittal) around a single axis that runs transversely Thus hinge joints are uniaxial joints. The joint capsule of these joints is thin and lax anteriorly and posteriorly where movement occurs; however, the bones are joined by strong, laterally placed collateral ligaments. Example: the elbow joint is a hinge joint.  Synovial Joints 3. Saddle joints Permit abduction and adduction as well as flexion and extension, movements occurring around two axes Thus saddle joints are biaxial joints that allow movement in two planes, sagittal and frontal. The performance of these movements in a circular sequence (circumduction) is also possible. The opposing articular surfaces are shaped like a saddle (i.e., they are reciprocally concave and convex). The carpometacarpal joint at the base of the 1st digit  Synovial Joints 4. Condyloid joints Permit flexion and extension as well as abduction and adduction Thus condyloid joints are also biaxial. However, movement in one plane (sagittal) is usually greater (freer) than in the other. Circumduction, more restricted than that of saddle joints, is also possible. The metacarpophalangeal joints (knuckle joints) are condyloid joints.  Synovial Joints 5. Ball and socket joints Allow movement in multiple axes and planes flexion and extension, abduction and adduction, medial and lateral rotation, and circumduction Thus ball and socket joints are multiaxial joints. In these highly mobile joints, the spheroidal surface of one bone moves within the socket of another. Example: the hip joint is a ball and socket joint in which the spherical head of the femur rotates within the socket formed by the acetabulum of the hip bone.  Synovial Joints 6. Pivot joints Permit rotation around a central axis; Thus they are uniaxial. In these joints, a rounded process of bone rotates within a sleeve or ring. The median atlantoaxial joint is a pivot joint in which the atlas (C1 vertebra) rotates around a finger-like process, the dens of the axis (C2 vertebra), during rotation of the head. FIGURE 17. The six major types of synovial joints plane, hinge, saddle, condyloid, ball and socket, and pivot  Body cavities and membranes BODY CAVITIES Spaces within the body that help protect, separate, and support internal organs. Bones, muscles, and ligaments separate the various body cavities from one another.  Dorsal cavity divided into cranial and vertebral cranial cavity : hollow space of the head in the cranial bones which contains the brain. Vertebral (spinal) canal In bones of the vertebral column (backbone), which contains the spinal cord and the beginnings of the spinal nerves. cranial cavity and vertebral canal are continuous with one another. the meninges and a shock absorbing fluid surround the brain and spinal cord. 4/10/2023 72   Ventral cavity Thoracic and abdominopelvic cavities. Are major body cavities of the trunk Thoracic cavity or chest cavity : is formed by the ribs, the muscles of the chest, the sternum (breastbone), and the thoracic (chest) portion of the vertebral column. Contains: pleural cavities Each pleural cavity surrounds one lung and also contains a small amount of lubricating fluid. Mediastinum: central portion of the thoracic cavity is between the medial walls of the two pleural cavities Extends from the sternum to the vertebral column, and from the first rib to the diaphragm 4/10/2023 73 contains all thoracic organs except the lungs themselves.  Structures in the mediastinum are the heart, esophagus, trachea, thymus, and several large blood vessels that enter and leave the heart. Pericardial cavity is a space that surrounds the heart and contains a small amount of lubricating fluid. Diaphragm: is a dome-shaped muscle that separates the thoracic cavity from the abdominopelvic cavity. Abdominopelvic cavity extends from the diaphragm to the groin and is encircled by the abdominal muscle wall and the bones and muscles of the pelvis. 4/10/2023 74  Membranes Membrane is a thin pliable tissue that covers, lines, partitions, or connects structures. Example: a slippery double- layered membrane called a serous membrane that covers the viscera within the thoracic and abdominal cavities and also lines the walls of the thorax and abdomen. 4/10/2023 75..The parts of a serous membrane are 1. parietal layer: a thin epithe-lium that lines the walls of the cavities 2. visceral layer: a thin epithelium that covers and adheres to the viscera Because the parietal and visceral membranes are continuous with one another, they form a serous sac. small amount of lubricating fluid (serous fluid) within the serous reduces friction between the two layers, 4/10/2023 76  Peritoneum is the serous membrane of the abdominal cavity Visceral peritoneum: covers the abdominal viscera, Parietal peritoneum lines the abdominal wall and covers the inferior surface of the diaphragm. Between them is the peritoneal cavity, which contains a small amount of lubricating fluid. organs surrounded by the peritoneal cavity are referred to as intraperitoneal. Retroperitoneal organs:- are located between the parietal peritoneum and the posterior abdominal wall 4/10/2023 77  Median plane section 4/10/2023 78 4/10/2023 79  Serosa 4/10/2023 80  Naming of serous membranes (serosa) with 2 adjectives: 1.) parietal or visceral Parietal serosa forms the outer wall of the cavity Visceral serosa covers the visceral organ 2.) pericardial, pleural, or peritoneal* Pericardial: heart Pleural: lungs Peritoneal: abdominal 4/10/2023 81 *The 2nd adjective can become a noun: pericardium, pleura, peritoneum 4/10/2023 82  Body Cavities and Membranes The median space in the thoracic cavity is called the mediastinum. It contains the heart, thymus, esophagus, trachea, and major blood vessels that connect to the heart. 4/10/2023 83  Body Cavities and Membranes Within the mediastinum, the heart is enclosed by a two-layered serous membrane called the pericardium. 4/10/2023 84  The Abdominopelvic Cavity The abdominopelvic cavity consists of an abdominal cavity and a pelvic.cavity. The peritoneum is a moist, two-layered serous membrane that lines the abdominopelvic cavity. 4/10/2023 1-85 4/10/2023 86 4/10/2023 87