Module 1: Anatomy and Physiology Introduction PDF

MODULE 1: ANATOMY AND PHYSIOLOGY MODULE 1: 1NUR6|Dr. James Rabago INTRODCUCTION TO ANATOMY AND Transcriber: Jenaya Alena R. Soriano...

MODULE 1: ANATOMY AND PHYSIOLOGY MODULE 1: 1NUR6|Dr. James Rabago INTRODCUCTION TO ANATOMY AND Transcriber: Jenaya Alena R. Soriano PHYSIOLOGY AND HOMEOSTASIS INTRODUCTION walls of their air sacs are very thin, they can exchange gases and provide oxygen to the ANATOMY body. § The study of the structure and shape of the body and its parts and their relationships to one another, - Anatomy precedes physiology this includes its position, location, name, etc. § The term anatomy is derived from the Greek words STRUCTURAL ORGANIZATION The simplest of the structural ladder is the meaning to cut (tomy) apart (ana), is related most chemical level. Atoms, tiny building blocks of closely to gross anatomical studies because in such matter, combine to form molecules such as studies, preserved animals or their organs are water, sugar, and proteins, like those that make up our muscle. dissected to be examined. Molecules in turn associate in specific ways ANATOMY CHEMICAL to form microscopic cells or the smallest units The study of large and easily observable of all living things. structures. These are organs that are observed without specialized equipment or The most common chemicals in our body GROSS is seen with the naked eye. are carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur. EXAMPLES: bones, heart, pancreas, etc. The study of body structures that are too Atoms → Molecules → Microscopic Cells small to be seen with the naked eye. This CELLS are the basic unit of life. This includes needs specialized equipment to be viewed the compartments and organelles (e.g., MICROSCOPIC because it consists of the small units of the mitochondria, nucleus) that are moving and body. reproducing. These organelles function to sustain life. CELLULAR EXAMPLES: tissues and cells. Our body also have different types of cells such as epithelial cells (i.e., squamous, PHYSIOLOGY cuboidal, and columnar) which provides § The study of how the body and its parts work or protection. The simplest living creatures are composed function which covers in studying how different of single cells, but in complex organisms organs have several functions, determining the such as trees or human beings continues on function of a certain organ, etc. this level. TISSUE TISSUES consists of groups similar cells that PHYSIOLOGY have a similar structure, function, and This details the general function of and extracellular substances they release. There organ. These include the specific functions are four basic types of tissues and each of organs that is done regularly to monitor its plays a definite but different role in the SYSTEMIC functioning. body. An ORGAN is a structure composed of two EXAMPLES: heart → pumps blood, inhaling or more tissue types that performs a specific and deflating of lungs, etc. ORGAN function for the body. Extremely complex These are the molecular processes inside a functions become possible. cell. An ORGAN SYSTEM is a group of organs that work together to accomplish a common EXAMPLES: with the help of the respiratory CELLULAR purpose. system, the RBC takes up oxygen which is part of the cellular respiration; anaerobic ORGAN SYSTEM EXAMPLE: the heart and the blood vessels of and aerobic respiration, diffusion of O2, the cardiovascular system circulate blood Sodium- Potassium Cycle, etc. continuously to carry nutrients and oxygen to all body cells. RELATIONSHIP OF ANATOMY AND PHYSIOLOGY This represents the highest level of structural organization. The organismal level is the sum § Anatomy and physiology are always inseparable. ORGANISM total of all structural levels working together The parts of the body form a well-organized unit, to keep us alive. and each of those parts has a job to do to make the body operate as a whole. o EXAMPLE. the lungs are not muscular chambers like the heart and so cannot pump blood through the body, but because of the Page 1 of 7 TYPES OF TISSUE These muscles are distinct from the muscles of the heart and of other hollow organs 1. EPITHELIAL – the lining, covering, and glandular tissue of the body. Covering and lining epithelium 4. NERVOUS SYSTEM – the body’s fast-acting control covers all free body surfaces. Epithelial functions system. It consists of the brain, spinal cord, nerves, include protection, absorption, filtration, and and sensory receptors. secretion. o The body must be able to respond to stimuli coming from outside the body and from 2. CONNECTIVE – connect body parts. It is found inside the body everywhere in the body. It is the most abundant and widely distributed of the tissue types. primarily COMPONENTS IN NERVOUS SYSTEM Detect changes in temperature, pressure, or involved in protecting, supporting, cushioning, and light, and send messages via electrical insulating other body tissues. SENSORY RECEPTORS signals called NERVE IMPULSES to the central nervous system → constantly informed what is going on. 3. MUSCULAR – are highly specialized to contract or These are the muscles or glands, which are shorten which generates the force required to organs that produce secretions or hormones. produce movement. In order to contract, muscle EFFECTORS The central nervous system assesses the must also be irritable or able to respond to stimuli. information from the receptors and responds by activating the effectors. 4. NERVOUS – NEURONS receive and send electrochemical impulses from one part of the 5. ENDOCRINE SYSTEM – controls body activities, but it body to another; thus, irritability and conductivity acts more slowly. Endocrine glands produce are their two major functional characteristics. chemical molecules called HORMONES and release them into the blood to travel to distant ORGAN SYSTEM target organs. o The endocrine glands include the pituitary, 1. INTEGUMENTARY SYSTEM – the external covering of thyroid, parathyroids, adrenals, thymus, the body, or the skin, including the hair and pancreas, pineal, ovaries, and testes. fingernails. It waterproofs the body and cushions o The endocrine glands are not connected and protects the deeper tissues from injury. anatomically in the same way that the parts of o It produces Vitamin D with the help of sunlight other organ systems are. and excretes salts in perspiration and helps regulate body temperature. 6. CARDIOVASCULAR SYSTEM – the primary organs o SENSORY RECEPTORS located in the skin alert us under this system are the heart and blood vessels. to what is happening at the body surface. Using blood as a carrier, the cardiovascular system delivers oxygen, nutrients, hormones, and other 2. SKELETAL SYSTEM – consists of the bones, substances to, and picks up waste such as CO2 cartilages, joints. It supports the body and from cells near sites of exchange. provides a framework that the skeletal muscles o White blood cells and chemicals in the blood use to cause movement. help to protect the body from such foreign o It has protective functions (e.g., the skull invaders as bacteria, viruses, and tumor cells. encloses and protects the brain) and the cavities of the skeleton are the sites 7. LYMPHATIC SYSTEM – complements that of the where blood cells are formed. cardiovascular system. Its organs include lymphatic o The hard substance of bones acts as a vessels, lymph nodes, and other lymphoid organs storehouse for minerals. such as the spleen and tonsils. o The lymphatic vessels return the fluid leaked 3. MUSCULAR SYSTEM – the muscles of the body into tissues from the blood into the have only one function –to contract or shorten. bloodstream → enough blood to continuously When this happens, movement occurs. This circulate through the body. system reflects the mobility of the body as a o The lymph nodes and other lymphoid organs whole, the large, fleshy muscles attached to the help to cleanse the blood and house white bones. blood cells involved in immunity. o When these contract, you are able to stand erect, walk, jump, grasp, throw a ball, or 8. RESPIRATORY SYSTEM – keep the body supplied with smile oxygen and to remove CO2. It consists of the nasal passages, pharynx, larynx, trachea, bronchi, and - The skeletal muscle forms the muscular system. lungs. Page 2 of 7  o Within the lungs are tiny air sacs called ALVEOLI Every living organism must be able to maintain its where gases are exchanged with blood boundaries so that its “inside” remains distinct from its through its thin walls. “outside”. 9. DIGESTIVE SYSTEM – a tube running through the Every cell of the human body is surrounded by an body from mouth to anus. The organs under this external membrane that separate its contents from the system include the oral cavity, esophagus, outside interstitial fluid (fluid between cells) and allows stomach, small and large intestines, and rectum entry of needed substances while generally preventing plus a number of accessory organs (liver, salivary entry of potentially damaging or unnecessary glands, pancreas, etc.). Its role is to break down substances. food and deliver the resulting nutrients to the blood for dispersal to body cells. CHARACTERISTICS OF LIFE The specific interrelationships among the o The breakdown activities that begin in the individual parts of an organism, and how mouth are completed in the small intestine → those parts interact to perform specific major function is to absorb nutrients and function. ORGANIZATION reabsorb water. All organisms are composed of one or more o The undigested food that remains in the tract cells. In turn, cellular function depends on leaves the body through the anus as FECES. the precise organization of large molecules. The ability to use energy to perform vital COMPONENTS IN NERVOUS SYSTEM functions, such as growth, movement, and The BILE it produces helps to break down reproduction. Our cells have specialized LIVER proteins that can break down food to use as fats. Delivers digestive enzymes to the small METABOLISM a source of energy. PANCREAS intestine and it has both endocrine and digestive functions. EXAMPLE. Our brain needs glucose and metabolism breaks down glucose from the food we eat. 10. URINARY SYSTEM – removes the nitrogen-containing Or IRRITABILITY is the ability to sense changes wastes from the blood and flushes them from the or stimuli in the environment and adjust to body in URINE. It is composed of the kidneys, ureters, those changes. All body cells are responsive to some extent since we have receptors. bladder, and urethra. RESPONSIVENESS o It maintains the body’s water and salt EXAMPLE: if you accidentally touch a hot balance, regulating the acid-base balance of pan, you involuntarily pull your hand away from the painful stimulus; fight or flight the blood, and helping to regulate normal response. blood pressure. An increase in the size or number of cells, which produces an overall enlargement in - This system is sometimes called EXCRETORY SYSTEM all or part of an organism, cell size, or amount of substance. which disposes nitrogen (urea and uric acid) from GROWTH the body through urine which contains AMMONIA. EXAMPLE. Bones grow when the number of bone cells increase and it becomes surrounded by mineralized materials. 11. REPRODUCTIVE SYSTEM – the role of this system is to The changes an organism undergoes produce offspring. through time, beginning with fertilization and ending at death. It involves growth and COMPONENTS IN REPRODUCTIVE SYSTEM differentiation. TESTES It produces SPERM. DIFFERENTIATION involves changes in a cell’s OVARIES It produces EGGS or OVA. structure and function from an immature, DEVELOPMENT Provides the site for development of the generalized state to a mature, specialized UTERUS fetus (immature infant) once fertilization state. has occurred. EXAMPLE. Following fertilization, immature These are the scrotum, penis, accessory cells differentiate to become specific type MALE REPRODUCTIVE glands, and the duct system which carries of cells, such as skin, bone, and muscle cell sperm outside of the body. which forms tissue and organs. The female duct system consists of the FEMALE REPRODUCTIVE Formation of new cells or new organisms. uterine, tubes, uterus, and vagina. Reproduction cells allows for growth and REPRODUCTION development and prevents extinction of MAINTAINING LIFE species. CELLULAR Original cells divides producing two identical REPRODUCTION daughter cells used for growth or repair. Organ systems do not work in isolation; instead they work together to promote the well-being of the entire body Task of the reproductive system, which produces egg and sperm. Its function is REPRODUCTION regulated very precisely by HORMONES of the endocrine system. Page 3 of 7  The normal body temperature (37 C) must be maintained if chemical MOVEMENT reactions are to continue at life- § It includes all the activities promoted by the sustaining levels. muscular system, such as propelling ourselves from If body temperature drops below 37 C one place to another and manipulating the (98.6 F), metabolic reactions become external environment with our fingers. slower and slower and finally stop. § Occurs when substances such as blood, foodstuffs, BODY TEMPERATURE If body temperature is too high, air, and urine are propelled through internal organs chemical reactions proceed too rapidly of the systems. and body proteins begin to breakdown. At either extreme, death occurs. DIGESTION Most body heat is generated by the § The process of breaking down ingested food into activity of the skeletal muscles and simple molecules that can then be absorbed into dissipated via blood circulating close to the skin surface or by evaporation of the blood. sweat. § The nutrient-rich blood is distributed to all body cells The force extended on the surface of by the cardiovascular system, where body cells use the body by the weight of air is referred these simple molecules for energy and raw as ATMOSPHERIC PRESSURE. materials. Breathing and the exchange of oxygen and carbon dioxide in the lungs depend ATMOSPHERIC PRESSURE EXCRETION on appropriate atmospheric pressures. § The process of removing EXCRETA or wastes from High altitudes → thin air and the body. Several organ systems participate in atmospheric pressure is lower → gas excretion. exchange may be too slow to support cellular metabolism. o EXAMPLE: the digestive system → feces; urinary system → urine and; skin → sweats. THE LANGUAGE OF ANATOMY SURVIVAL NEEDS § The goal of nearly all body systems is to maintain life ANATOMICAL POSITION refers to the body in the which requires several factors be available referred standard position; body is erect with feet parallel and as SURVIVAL NEEDS arms hanging at the sides with the palms facing forward It is important to understand this position because most SURVIVAL NEEDS of the body terminology used refers to this body The body takes in through food, contain positioning regardless of the position the body happens the chemicals used for energy and cell to be in. building. CARBOHYDRATES are the major energy- providing fuel for body cells. PROTEINS to a lesser extent, and FATS for building cell NUTRIENTS structure and cushion body organs and provide reserve fuel. MINERALS and VITAMINS are required for the chemical reactions that go on in cells and for oxygen transport in the blood. The chemical reactions from foods require oxygen, human cells can survive only a few minutes without it. OXYGEN It is made available to the blood and body cells by the cooperative efforts of the respiratory and cardiovascular system. It accounts for 60 to 80 percent of body DIRECTIONAL TERMS weight, depending on the age of the individual. It is the single most abundant § Allow medical personnel and anatomists to explain chemical substance in the body and exactly where one body structure is in relation to provides the fluid base for body another. WATER secretions and excretions. We obtain water chiefly from ingested food or liquids, and we lose it by evaporation from the lungs and skin and in body excretions. Page 4 of 7  DIRECTIONAL TERMS 2. FRONTAL SECTION – a cut along a lengthwise plane TERM DEFINITION EXAMPLE that divides the body into anterior and posterior SUPERIOR Toward the head end parts. It is also called CORONAL SECTION. or upper part of a The forehead is superior (CRANIAL OR structure or the body; to the nose. CEPHALIC) 3. TRANSVERSE SECTION – a cut along a horizontal ABOVE. plane, dividing the body or organ into superior and Away from the head inferior parts. It is also called CROSS SECTION. INFERIOR end or toward the The navel is inferior to (CAUDAL) lower part of a structure the breastbone. or the body; BELOW. Toward or at the front ANTERIOR The breastbone is of the body; IN FRONT (VENTRAL) anterior to the spine. OF. Toward or at the POSTERIOR The heart is posterior backside of the body; (DORSAL) to the breastbone. BEHIND. Toward or at the The heart is medial to MEDIAL midline of the body; the arm. - Sectioning a body or one of its organs along ON THE INNER SIDE OF. different planes often results in different views Away from the midline The arms are lateral to LATERAL of the body; ON THE BODY CAVITIES the chest. OUTERSIDE OF. The collarbone is Between a more The dorsal and ventral body cavities differ in their mode intermediate between INTERMEDIATE medial and a more the breastbone and of embryological development and in their lining lateral structure. the shoulder. membranes. Close to the origin of the body part or the The elbow is proximal PROXIMAL DORSAL BODY CAVITY point of attachment to the wrist. of a limb to the trunk. § It has two subdivisions which are continuous to each Farther from the origin other: cranial cavity and the spinal cavity. of a body part or the The knee is distal to DISTAL point of attachment the thigh. DORSAL BODY CAVITY of a limb to the body trunk. The space inside the bony skull. The CRANIAL CAVITY brain is well protected because of the SUPERFICIAL Toward or at the body The skin is superficial to cranial cavity. (EXTERNAL) surface. the skeleton. Extends from the cranial cavity to the end of the spinal cord. The spinal cord is SPINAL CAVITY protected by the bony vertebrae which DEEP Away from the body The lungs are deep to surround the spinal cavity and form the (INTERNAL) surface; MORE INTERNAL. the rib cage. spine VENTRAL BODY CAVITY BODY PLANES AND SECTIONS § Is much larger than the dorsal body cavity. It § When preparing to look at the internal structures of contains all the structures within the CHEST and the body, medical student make a SECTION or cut. ABODMEN, that is, the organs in those regions. When the section is made through the body wall or through an organ, it is made along an imaginary VENTRAL BODY CAVITY line called PLANE. Separated from the rest of the ventral cavity by a dome-shaped muscle which TYPES OF BODY PLANES AND SECTIONS is the DIAPHRAGM. The organs in the thoracic cavity are 1. SAGITTAL SECTION – is a cut along the lengthwise or THORACIC CAVITY protected by the rib cage. A central longitudinal plane of the body, dividing the body region called MEDIASTINUM, or the space within the lungs, separates the into right and left parts. lungs into right and left cavities; it houses o If the cut is down the median plane of the the heart, trachea, and several other body and the right and left parts are equal in visceral organs. The cavity inferior to the diaphragm. size, it is called MIDSAGITTAL SECTION. There is no actual physical structure o All other sagittal sections are PARASAGITTAL dividing the abdominopelvic cavity. ABDOMINOPELVIC SECTIONS (para → near). CAVITY The pelvic cavity is not immediately inferior to the abdominal cavity, but rather tips away from the abdominal Page 5 of 7  cavity in the posterior direction (e.g., SEROUS MEMBRANES urinary bladder, reproductive organs, and part of large intestine). It is the space within the diaphragm and pelvis. The walls of the body cavities and the surface of internal organs are in contact with membranes called SEROUS The abdominal cavity contains the stomach, intestines, liver, spleen, MEMBRANES, which are doubled layer. These pancreas, and kidneys. membranes secrete serous fluids such as water and minerals. - When the body is subjected to trauma, the most vulnerable abdominopelvic organs are those within SEROUS MEMBRANES The layer that lines the walls of the the abdominal cavity → walls are formed only of PARIETAL cavities. trunk muscles and are not reinforced by bone. The layer covering the internal organs or VISCERAL - The line of SACRAL PROMONTORY is drawn obliquely the viscera. to the anterior part of the pubic bone which is the CAVITY The fluid-filled space between the membranes. imaginary line that separates the abdominal cavity from the pelvic cavity. QUADRANTS AND REGIONS § The quadrants are named according to their relative locations with respect to anatomical position THORACIC CAVITY MEMBRANES A. PERICARDIAL CAVITY – containing the heart, is housed in the mediastinum. It includes the parietal pericardium, visceral pericardium, and pericardial cavity. § A scheme commonly used by medical personnel B. PLEURAL CAVITY – each of the two pleural cavities divides the abdominopelvic cavity into four more or houses a lung. It includes the parietal pleura, less equal regions. visceral pleura, and pleural cavity which contains pleural fluid. OTHER BODY CAVITIES C. PERITONEAL CAVITY – houses many internal organs, 1. ORAL AND DIGESTIVE CAVITY – the oral cavity such as the liver, the digestive organs, and the contains the teeth and tongue. This cavity is part of reproductive organs. It includes the parietal and continuous with the digestive organs, which peritoneum, visceral peritoneum, and peritoneal open to the exterior at the anus. cavity which contains peritoneal fluid. o In addition to covering the organs, a double- 2. NASAL CAVITY – located within and posterior to the folded sheet of visceral peritoneum attaches nose. It is part of the respiratory system. the digestive organs at certain points to the posterior abdominopelvic cavity wall. 3. ORBITAL CAVITY – the orbital cavities in the skull o These regions of double-folded visceral house the eyes and present them in an anterior peritoneum are called MESENTRIES which position. provide a pathway for nerves and blood vessels to reach the digestive organs. 4. MIDDLE EAR CAVITY – the middle ear cavities o The most enormous mesenteric pouch carved into the skull lie just medial to the eardrums. contains adipose tissue is suspended from the These cavities contain tiny bones that transmit inferior border of the stomach, contributing to sound vibrations to the hearing receptors in the a big belly. inner ears. - Some abdominal organs are tightly adhered to the posterior wall and are covered by peritoneum only on their cavity side. These organs have Page 6 of 7  RETROPERITONEAL location and include kidneys, original stimulus or reduce its intensity. It is the ureters, adrenal glands, pancreas, large intestine, complete opposite which commonly happens in and urinary bladder. our body. o EXAMPLE: regulating blood sugar levels (↑ INFLAMMATION OF SEROUS MEMBRANES blood sugar levels = ↓ insulin PERICARDITIS Inflammation of the pericardium PLEURISY Inflammation of the pleura PERITONITIS Inflammation of the peritoneum. B. POSITIVE FEEDBACK – occurs when the initial stimulus further stimulates the response which causes progressive deviation from set point towards HOMEOSTASIS outside of normal range. o It is not directly used to homeostasis and is HOMEOSTASIS describes the body’s ability to maintain generally associated with injury and disease. relatively stable internal conditions even though the o EXAMPLE: ↑ oxytocin = ↑ contract; deeper outside world is continuously changing. (homeo = same; wound = ↑ platelets stasis = standing still) VARIABLES It indicates a dynamic state of equilibrium or a balance § These are measures of body properties that may in which internal conditions change and vary but always change in value. It can be changed by internal or within relative narrow limits. Needs are being adequately external influence. met and it is functioning smoothly. o These are values that must be brought to its normal range otherwise it becomes Communication within the body is essential for pathological. homeostasis and Is accomplished by the nervous and endocrine systems, which use electrical signals delivered NORMAL VALUES by nerves or bloodborne hormones as information SODIUM LEVEL 135 – 145 mEq/L carriers. HEART RATE 60 – 100 bpm BLOOD PRESSURE 120 – 129/ 80 mmHg Homeostasis is important that most disease can be regarded as being the result of its disturbance, a pH 7.35 – 7.45 condition called HOMEOSTATIC IMBALANCE. SET POINT COMPONENTS OF HOMEOSTASIS § Normal value of a variable (e.g., overtime, body A type of sensor that monitors and responds to changes in the temperature fluctuates around a set point. environment. It responds to such changes called STIMULI by sending RECEPTOR information to the second component. Information flows from the receptor → control system along the AFFERENT PATHWAY. Determines the level at which variable is to be maintained. This component CONTROL CENTER analyzes the information it receives and then determines the appropriate response or course of action. Provides the means for the control center’s response to the stimulus. Information flows from the control center END OF MODULE → effector along the EFFERENT PATHWAY (efferent information exits control center) EFFECTOR The results of the response then feedback to influence the stimulus either by reducing the amount of change → whole control mechanism is shut off; or by increasing the amount of change → reaction continues at an even faster rate. NEGATIVE FEEDBACK AND POSITIVE FEEDBACK A. NEGATIVE FEEDBACK – the net effect of the response to the stimulus is to either shut off the Page 7 of 7