Health Science: Anatomy and Physiology Introduction PDF

Health Science: Anatomy and Physiology Lance Kevin Chan, MD  Definitions Scientific discipline that Anatomy investigates the structure of the...

Health Science: Anatomy and Physiology Lance Kevin Chan, MD  Definitions Scientific discipline that Anatomy investigates the structure of the body Developmental Cytology Histology Gross Anatomy Examines tissues, Studies the The study of Examnies the which are composed structural changes structures that can structural features of cells and the that occur between be examined of cells using a materials conception and without the aid of a microscope surrounding them by adulthood microscope using a microscope  Definitions Gross Anatomy Systemic Regional Study of the body by systems Study of the body by areas e.g. skeletal, muscular, e.g. head, abdomen, thorax cardiovascular  Approaches to Anatomy Involves looking at the exterior of the body to visualize structures deeper Surface inside the body Anatomy E.g. when identifying structures affected after a stab wound Use of xray, ultrasound, MRI, endoscopes, and other technologies to Anatomical create pictures of internal structures Imaging Allows to look inside the body with amazing accuracy and without the trauma and risk of exploratory surgery Clinical application of anatomy Physical Composed of inspection, percussion, palpation, and auscultation Exam Uses instruments such as stethoscope and ophthalmoscope  Definitions Scientific discipline that deals with the Physiology processes or functions of living things Examines the process occurring in cells Cell Physiology e.g. manufacturing of proteins by cells Focuses on the function of organ systems Systemic Physiology e.g. digestion of food  Definitions Medical science dealing with all aspects of disease, with emphasis on the cause of and Pathology development of abnormal conditions, as well as the structural and functional changes resulting from disease Focuses on the changes in function and Exercise Physiology structure caused by exercise Structural and Functional Organization of the Human Body Levels of Human Body Organization Chemical Cell Tissue Organ Organ Organism System Chemical Level Determines the structural and functional characteristic of all organisms Molecule’s structure determined its function E.g. collagen molecules are strong rope like protein fibers that gives skin structural strength and flexibility Cell Level Cells are the basic structural and functional units of organisms Organelles – smaller structures inside the cell that carry out particular functions Tissue Level Tissue – Group of similar cells and the materials surrounding them Cells and surrounding material determine the function of the tissue Can be classifies into: ○ Epithelial ○ Connective ○ Muscle ○ Nervous Organ Level Organ – composed of two or more tissue types that together perform one or more common functions E.g. esophagus, stomach, small intestine, colon, liver, gallbladder Organ System Level Organ system – a group of organs that together perform a common function of set of functions E.g. urinary system consists of kidneys, ureters, urinary bladder, and urethra Kidneys produce urine, which is transported to the urinary bladder, then eliminated through the urethra Organism Level Any living thing considered as a whole, whether composed of one cell or of trillions of cells The human organism is a network of organ systems that are mutually dependent upon one another Organ System Level The 11 major organs systems: Integumentary Lymphatic Skeletal Respiratory Muscular Digestive Nervous Urinary Endocrine Reproductive Cardiovascular Integumentary System Parts: skin, hair, nails, sebaceous glans, and sweat glands Functions: Provides protection Regulates temperature Prevents water loss Helps produce vitamin D Skeletal System Parts: bones, cartilages, ligaments, and joints Functions: Provides protection and support Allows body movements Produces blood cells Stores minerals and adipose tissue Muscular System Parts: muscles attached to connective tissue sheets or skeletons by tendons Functions: Produces body movements Maintains posture Produces body heat Lymphatic System Parts: lymphatic vessels, lymph nodes, thymus, spleen, and other lymphatic tissue Functions: Removes foreign substances from the blood and lymph Combats disease Maintains tissue fluid balance Absorbs dietary fats from the digestive tract Respiratory System Parts: lungs, diaphragm, respiratory passages Functions: Exchanges oxygen and carbon dioxide between blood and air Regulates blood pH Digestive System Parts: mouth, esophagus, stomach, intestines, liver, gallbladder, and other accessory organs Functions: Performs mechanical and chemical processes of digestion Absorption of nutrients Elimination of wastes Nervous System Parts: brain, spinal cord, nerves, and sensory receptors Functions: Major regulatory system that detects sensations and controls movement, physiological processes, and intellectual functions Endocrine System Parts: endocrine glands including hypothalamus, pituitary gland, thyroid gland, adrenal gland, gonads, and other tissues that secrete hormones Functions: Regulatory system that influences metabolism, growth, reproduction, and many other function Cardiovascular System Parts: heart, blood vessels, and blood Functions: Transport nutrients, waste products, gases, and hormones throughout the body Plays a role in the immune response and regulation of body temperature Urinary System Parts: kidneys, ureters, urethra, and urinary bladder Functions: Removes waste products from blood Regulates pH, ion balance, and water balance Reproductive System Parts: Female – ovaries, uterine tubes, uterus, vagina, mammary glands, and associated structures Male – testes, accessory structures, ducts, and penis Functions: Female: Produce oocytes, site of fertilization and fetal development, produces milk, produce hormones Male: Produces and transfers sperm cells to the female and produces hormones that influence sexual functions and behavior Homeostasis Homeostasis Homeostasis is the maintenance of a relatively constant environment within the body Body must actively regulate body conditions that are constantly changing Variables are the changes in the body conditions with values are not constant; such as temperature, volume, blood pH, and chemical content For cells to function properly, all variables must be maintained within a narrow range Homeostasis Normal body temperature: 36.5 to 37.5 Celsius Homeostatic mechanisms include shivering and sweating to maintain normal body temperature near an ideal normal value, or set point As long as the body temperature remain within the normal range, homeostasis is maintained. Disease disrupts homeostasis and sometimes results in death  Feedback Loop Homeostasis is regulated by feedback loops Two types: 1. Negative feedback 2. Positive feedback  Feedback Loop Feedback loops have 3 components 1. Receptor – monitors the value of a variable by detecting stimuli 2. Control center – determines the set point for the variable and receives input from the receptor about the variable 3. Effector – generates the response that adjusts the value of a changed variable Negative Feedback Mechanism When any deviation from the set point is made smaller or is resisted The response by the effector is stopped once the variable returns to its set point Examples: Temperature regulation Blood pressure regulation Blood sugar regulation Thyroid hormone regulation Negative Feedback Mechanism More common compared to positive feedback mechanisms The hallmark of negative feedback – effectors stop their response once the variable has returned to its set point. They do not produce an indefinite response Positive Feedback Mechanism Occur when a response to the original stimulus results in the deviation from the set point becoming even greater Examples: Thrombin, which is responsible for blood clotting, stimulates even more thrombin production Child birth Milk production for breast feeding Positive Feedback Mechanism The hallmark of Positive feedback – the effectors continue the response beyond the set point until the original stimulus is removed Homeostasis Although homeostasis is the maintenance of a normal range of values, this does not mean that all variables remain within the same narrow range at all times. Some deviation may be beneficial such as increase in blood pressure during exercise Two basic principles: 1. Many disease states result from the failure of negative-feedback mechanisms to maintain homeostasis 2. Some positive feed back mechanisms can be detrimental instead of helpful Vicious Cycle When positive feedback mechanism become pathologic Example: inadequate delivery of blood to the heart Contraction of heart generates blood pressure. Heart pumps blood to itself through blood vessels outside the heart. Like other tissues, blood pressure must be maintained. With extreme blood loss, not enough blood is delivered to the heart. As a result, the heart pumps less blood which causes less blood to be delivered to the heart. This continues until the heart stops beating Vicious Cycle When positive feedback mechanism become pathologic Negative feedback may not be able to maintain homeostasis and positive feedback of ever-decreasing blood pressure can develop However, in moderate blood loss, negative feedback results in an increase in heart rate that restores blood pressure to normal Terminology and the Body Plan  Anatomical Position Refers to a person standing upright with the face directed forward, the upper limbs hanging to the sides, and the palms of the hands facing forward Provides a clear and consistent way of describing human anatomy and physiology Supine – lying face upward Prone – lying face downward Directional Terms Superior/Cephalic – above Inferior/Caudal – below Anterior/Ventral – in front of Posterior/Dorsal – behind Proximal – close to a point Distal – far from a point Medial – toward the midline Lateral – away from midline Superficial – closer to the surface Deep – toward the interior  Body Parts and Regions Central Region of Body Head Neck Trunk Thorax Abdomen Pelvis Chest cavity where Contains organs Contains the lungs and heart are such as liver, bladder and located stomach, and reproductive organs intestines  Body Parts and Regions Extremities Upper Limb (Extremity) Arm Forearm Wrist Hand Lower Limb (Extremity) Thigh Leg Ankle Foot Body Parts and Region The abdomen can be divided into 4 quadrants by 2 imaginary lines: one horizontal and one vertical that intersect in the navel: Right-upper Left-upper Right-lower Left-lower Body Parts and Region Can also be subdivided into 9 regions by two horizontal and two vertical lines Epigastric Left and Right Hypochondriac Umbilical Right and Left Lumbar Hypogastric Right and Left Iliac Body Parts and Region Health professionals use the quadrants or regions as reference points for locating underlying organs. e.g. The appendix is in the right-lower quadrant and pain of an acute appendicitis is usually felt there The gallbladder is in the right upper quadrant and the pain of gall stones is usually felt there  Planes Imaginary flat surfaces passing through the body A plane divides, or sections the body, making it possible to “look inside” and observe the body’s structure Necessary to identify a reference point to identify the location or level of the plane, such as “transverse plane through the umbilicus” Planes Sagittal plane – separates the body to left and right halves, a vertical plane parallel to the median plane Median plane – the vertical plane passing longitudinally though the body, dividing it into equal right and left halves  Planes Transverse (Horizontal) plane – runs parallel to the ground, dividing it into superior and inferior positions Frontal (Coronal) plane – divides the body into anterior and posterior halves Frontal (Coronal) Transverse Sagittal  Sections Organs are often sectioned to reveal their internal structure Longitudinal section – run lengthwise or parallel to the long axis, regardless of position of the body Transverse section or cross section – slices that are at right angles to the longitudinal axis Oblique section – slices that are not cut along the longitudinal or transverse Longitudinal Section Cross section Body Cavities Body Cavities The body contains two types of internal cavities: Dorsal body cavity Ventral body cavity Dorsal Body Cavity Encloses the organs of the nervous system, the brain and the spinal cord The two subdivisions of the dorsal body cavity are the: Cranial cavity – houses the brain Vertebral cavity – houses the spinal cord Both brain and spinal cord are covered by membranes call meninges Ventral Body Cavity Houses the vast majority of internal organs, collectively referred to as the viscera The ventral body cavity has two major subdivisions: Thoracic cavity Abdominopelvic cavity Thoracic Cavity More superior to the abdominopelvic cavity Primarily houses the heart and lungs Further subdivided into sections: ○ Two lateral pleural cavities, which encloses the lungs ○ A medial mediastinum, which houses the heart and its major blood vessels, the thymus, the trachea, and the esophagus Abdominopelvic Cavity Enclosed by the abdominal muscles and consists of: ○ The superior abdominal cavity ○ The inferior pelvic cavity Organs are housed within the peritoneal cavity Abdominopelvic Cavity Abdominal cavity – majority of digestive organs, such as stomach, the intestines, and the liver, in addition to the spleen Pelvic cavity – contains the urinary bladder, urethra, rectum of the large intestines, and the reproductive organs Serous Membranes Walls of the body cavities and the surface of the internal organs are in contact with membranes called serous membranes Double layered: Parietal serous membrane – lines the walls of the cavity Visceral serous membrane – lines the internal organs  Serous Membranes To understand the relationship, imagine pushing your fist (representing the organ) into a slightly deflated balloon (representing the membranes and cavity The portion of the balloon in contact with the fist represent the visceral serous membrane the outer part represents the parietal serous membrane Serous Membranes There is no air in between the two membranes. They are separated by a thin film of serous fluid produced by the membranes The serous fluid and the smooth serous membranes allow organs to move in the cavities Terms of Laterality Terms of Laterality Bilateral – structures having left and right members, such as kidneys Unilateral – organs occurring in only one side, such a spleen Ipsilateral – occurring in the same side of the body, such as right thumb and right big toe Contralateral – occurring in the opposite side of the body, such as left hand and right leg Terms of Movement Terms of Movement Terms used to describe movements of the limbs and other parts of the body Movements are defined in relationship to the anatomical position, with movements occurring within, and around axes aligned with, specific anatomical planes Most occur at joints where two or more bones or cartilages articulate with one another, several non-skeletal structures exhibit movement (e.g. tongue, lips, eyelids) Terms of Movement Flexion – indicates bending or decreasing angle between bones or parts of body Extension – straightening or increasing the angle between the bones and body parts Terms of Movement Flexion – indicates bending or decreasing angle between bones or parts of body Extension – straightening or increasing the angle between the bones and body parts Terms of Movement Dorsiflexion – flexion at the ankle joint, as occurs when walking uphill or lifting the front of the foot off the ground Plantarflexion – bend the foot and toes towards the ground, as when standing on your toes Terms of Movement Abduction – moving away from the median plane Adduction – moving towards the median plane Terms of Movement Circumduction – circular movement that involves the sequential flexion, abduction, extension, and adduction in such a way the distal end moves in a circle Terms of Movement Rotation – involves turning or revolving a part of the body around its longitudinal axis Medial rotation (Internal rotation) – brings the anterior surface of the limb closer to the median plane Lateral rotation (External rotation) – takes the anterior surface away from the median plane Terms of Movement Pronation – rotates the radius medially so that the palm of the hand faces posteriorly and the dorsum faces anteriorly Supination – the opposite rotational movement, rotating the radius laterally and uncrossing from the ulna, returning the pronated forearm to the anatomical position Terms of Movement Eversion – moves the sole of the foot away from the median plane, turning the sole laterally. When the foot is fully everted, it is also dorsiflexed Inversion – moves the sole of the foot towards the median plane. When fully inverted, it is also plantarflexed Terms of Movement Protrusion – movement anteriorly Retrusion – movement posteriorly Elevation – raises or moves a part superiorly Depression – lowers or moves a part inferiorly  THANKS! Sources: Seeley’s Anatomy and Physiology 13th edition Moore’s Clinical Anatomy 8th edition CREDITS: This presentation template was created by Slidesgo, including icons by Flaticon and infographics & images by Freepik