Tortora Anatomy Chapter 1
Tortora Anatomy Chapter 1 LS-ANATO 219
Popular in Functional Anatomy I
Popular in LS-ANAT
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
verified elite notetaker
This 16 page Class Notes was uploaded by Taylor Swifty on Monday September 19, 2016. The Class Notes belongs to LS-ANATO 219 at University of Missouri - Kansas City taught by Tara Allen in Fall 2016. Since its upload, it has received 12 views. For similar materials see Functional Anatomy I in LS-ANAT at University of Missouri - Kansas City.
Reviews for Tortora Anatomy Chapter 1
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 09/19/16
Chapter 1 An Introduction to The Human Body We are going to learn: how the human body is organized (structure) how the human body functions so that we can understand what happens when body is injured, diseased, or placed under stress. In this chapter, we’ll understand: how anatomists visualize the body basic anatomical vocabulary to describe body in a language common to both scientists & professionals. 1.1 – ANATOMY DEFINED Anatomy (a-NAT-o¯-me¯; ana-_up; _-tomy_process of cutting) study of structure and relationships among structures. first studied by dissection - the careful cutting apart of body structures to study their relationships today, we use imaging techniques to contribute to advancement of anatomical knowledge The anatomy of the human body can be studied at various levels of structural organization: microscopic (visible only with the aid of a microscope) macroscopic (visible without the use of a microscope). Anatomy deals mostly with structures of the body. Physiology deals with functions of body parts - how they work. Function can’t be separated completely from structure you will learn how structure of the body often reflects its functions Some of the structure–function relationships are visibly obvious: o tight connections between the bones of the skull, which protect brain. o bones of the fingers are more loosely joined to permit movements such as playing an instrument, grasping a baseball bat, retrieving a small object from the floor. o shape of the external ear assists in collection and localization of sound waves, which facilitates hearing. Other relationships are not as visibly obvious: o passageways that carry air into lungs branch extensively when they reach lungs. Tiny air sacs—about 300 million—cluster at ends of large number of airway branches. o vessels carrying blood into lungs branch extensively to form tiny tubes that surround small air sacs huge total surface area is the key to primary function of the lungs = efficient exchange of oxygen and carbon dioxide between air and blood. 1.2 – LEVELS OF BODY ORGANIZATION AND BODY SYSTEMS levels of organization of a language: letters of alphabet, words, sentences, paragraphs, and so on—can be compared to levels of organization of body organized from smallest to largest, six levels of organization will help you understand anatomy: o chemical, cellular, tissue, organ, system, and organismal levels of organization Chemical Level can be compared to letters of alphabet includes atoms = smallest units of matter that participate in chemical reactions includes molecules = two or more atoms joined together. Atoms: carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), and calcium (Ca), are essential for life. Two familiar molecules found in body are: o deoxyribonucleic acid (DNA) = genetic material passed from one generation to next o glucose, commonly known as blood sugar. Cellular Level molecules combine to form cells ≈ assembling letters into words Among the many kinds of cells in your body are muscle cells, nerve cells, and blood cells Cells structures composed of chemicals and are basic structural and functional units of an organism. are smallest living units in human body Tissue level Tissues are groups of cells and materials surrounding them that work together to perform a particular function four basic types of tissue in your body: epithelial tissue, connective tissue, muscular tissue, and nervous tissue. Epithelial tissue covers body surfaces, lines hollow organs and cavities, and forms glands. Connective tissue connects, supports, and protects body organs while distributing blood vessels to other tissues. Muscular tissue contracts (shortens) to make body parts move and generates heat. Nervous tissue carries information from one part of the body to another. Organ level different types of tissues joined together. Organs structures that are composed of 2 or more different types of tissues have specific functions and usually have recognizable shapes. Examples: stomach, heart, liver, lungs, and brain. o Stomach: outer covering is layer of epithelial & connective tissues that reduce friction when stomach moves and rubs against other organs underneath these layers is type of muscular tissue called smooth muscle tissue, which contracts to churn and mix food and push it on to next digestive organ small intestine. innermost lining, the epithelial tissue layer, produces fluid and chemicals responsible for digestion in stomach. System level also called organ-system level A system consists of related organs with a common function. o Example: Digestive system - breaks down and absorbs food. organs include mouth, salivary glands, pharynx (throat), esophagus (tube that carries food from the throat to the stomach), stomach, small intestine, large intestine, liver, gallbladder, and pancreas. Sometimes an organ is part of > 1 system o Example: Pancreas - has multiple functions, is included in the digestive and endocrine systems. Organismal level Organism = any living individual All the parts of the human body functioning together constitute total organism. 1.3 – LIFE PROCESSES All living organisms have certain characteristics that set them apart from nonliving things. The following are six important life processes of humans: Metabolism = sum of all the chemical processes that occur in the body. It includes the breakdown of large, complex molecules into smaller, simpler ones (catabolism) and the building up of complex molecules from smaller, simpler ones (anabolism) For example, food proteins are broken down into amino acids, building blocks that can then be used to build new proteins that make up muscles and bones. Responsiveness = the body’s ability to detect and respond to changes in its internal (inside the body) or external (outside the body) environment. Different cells in the body detect different sorts of changes and respond in characteristic ways. Nerve cells respond to changes in the environment by generating electrical signals, known as nerve impulses. Muscle cells respond to nerve impulses by contracting, which generates force to move body parts. Movement = motion of the whole body, individual organs, single cells, and structures inside cells Example #1: coordinated action of several muscles and bones allows you to move your body from one place to another by walking or running. Example #2: after you eat a meal that contains fats your gallbladder (an organ) contracts and releases bile into GI tract to help digest them. Example #3: when a body tissue is damaged or infected WBCs move from bloodstream into the affected tissue to help clean up and repair area. Example #4: Inside individual cells, various cell structures move from one position to another to carry out functions. Growth = increase in body size It may be due to an increase in (1) the size of existing cells, (2) the number of cells, or (3) the amount of material surrounding cells. Differentiation = process unspecialized cells go through to become specialized cells. Precursor cells (stem cells) can divide and give rise to cells that undergo differentiation Specialized cells differ in structure and function from unspecialized cells that gave rise to them. Example #1: specialized RBCs and several types of WBCs differentiate from same unspecialized cells in red bone marrow. Example #2: a single fertilized human egg cell undergoes tremendous differentiation to develop into a unique individual who is similar to, yet quite different from, either of his or her parents. Reproduction = formation of new cells through cell division. production of a new individual occurs through fertilization of an ovum by sperm cell to form a zygote followed by repeated cell divisions and differentiation of these cells. Although not all of these processes occur in cells throughout body all of the time, when any one of them ceases to occur properly cell death may occur when cell death is extensive and leads to organ failure result is death of the organism. 1.4 – BASIC ANATOMICAL TERMINOLOGY Scientists and health-care professionals use a common language of special terms when referring to body structures and their functions. Language of anatomy has precisely defined meanings that allow us to communicate clearly and unambiguously. Anatomists use a standard anatomical position and a special vocabulary for relating body parts to one another. Anatomical Position Anatomical position = standard position of reference for the description of anatomical structures. the body is upright subject stands erect facing the observer, with the head level and the eyes facing directly forward. lower limbs are parallel and the feet are flat on the floor and directed forward upper limbs are at the sides with the palms facing forward With the body in the anatomical position, it is easier to visualize and understand its organization into various regions and describe relationships of various structures. There are two terms used to describe a reclining body: If the body is lying face down, it is in the prone position If the body is lying face up, it is in the supine position. Regional Names The human body is divided into several major regions that can be identified externally These are the head, neck, trunk, upper limbs, and lower limbs. Head consists of the skull and face The skull encloses and protects brain The face is the front portion of the head that includes the eyes, nose, mouth, forehead, cheeks, and chin Neck is a modified portion of the trunk supports the head and attaches it to the remainder of the trunk Trunk consists of the neck, thorax, abdomen, and pelvis. Upper Limbs each upper limb (extremity) is attached to trunk consists of shoulder, armpit, arm (portion of limb from shoulder to elbow), forearm (portion of limb from elbow to wrist), wrist, and hand. Lower Limbs each lower limb (extremity) is attached to trunk consists of the buttock, thigh (portion of the limb from the buttock to the knee), leg (portion of the limb from the knee to the ankle), ankle, and foot. Groin the area on the front surface of the body marked by a crease on each side, where the trunk attaches to the thighs. Understanding the precise meaning of: arm and forearm in the upper limb thigh and leg in the lower limb is very important when reading or describing a clinical assessment. The anatomical term for a word is based on a Greek or Latin word or “root.” Example: the Latin word axilla is the armpit region o the axillary nerve is one of the nerves passing within the armpit region. Understanding the word roots of anatomical terms can help you learn the terms more easily. Planes and Sections Referencing various body regions enables you to study surface anatomy of the body. It is also possible to study internal structure of body by slicing the body in different ways and examining the sections. Planes are imaginary flat surfaces that pass through the body Sagittal plane is a vertical plane that divides body or organ into right and left sides when such a plane passes through the midline (imaginary vertical line that divides the body into equal left and right sides) of the body and divides it into equal right and left sides = midsagittal plane, or a median plane If the sagittal plane does not pass through the midline but instead divides the body into unequal right and left sides, it is called a parasagittal plane (para- = beside, near). Frontal, or coronal, plane divides the body or an organ into front and back portions. Transverse plane divides the body or an organ into upper and lower portions may also be termed a cross-sectional plane or horizontal plane Sagittal, frontal, and transverse planes are all at right angles to one another. An oblique plane passes through the body or organ at an oblique angle (any angle other than a 90_ angle). When you study a body region, you often view it in section. Sections are cuts of the body or one of its organs made along one of the planes A section produces a flat 2-D surface of the original 3-D structure. It is important to know the plane of the section so you can understand anatomical relationship of one part to another. EXHIBIT 1.A – Directional Terms Overview To help improve communication when discussing basic parts of the body and the relationships those parts have to one another, anatomists and health-care professionals use specific directional terms. Directional terms = words that describe the position of one body part relative to another Most used to describe relationship of one part of the body to another can be grouped into pairs that have opposite meanings. Example: superior means toward upper part of the body, and inferior means toward lower part of the body. have relative meanings make sense only when used to describe the position of one structure relative to another. Example: your knee is superior to your ankle, even though both are located in the inferior half of the body. Study the directional terms below: 1.5 – BODY CAVITIES Body cavities are spaces w/in the body that house internal organs. Bones, muscles, and ligaments separate various body cavities from one another. Cranial cavity cranial bones form a hollow space of the head called the cranial cavity, which contains the brain. Vertebral (spinal) canal the bones of the vertebral column (backbone) form it contains the spinal cord and the beginnings of the spinal nerves. The cranial cavity and vertebral canal are continuous with one another. Surround the brain and spinal cord: three layers of protective tissue meninges shock-absorbing fluid (CSF) Thoracic cavity (or chest cavity) is formed by ribs, muscles of the chest, sternum (breastbone), and thoracic (chest) portion of the vertebral column. has two pleurae (serous sacs) o Each double-layered pleura surrounds one lung o also contains a small amount of lubricating fluid in a potential space between the layers The central portion is an anatomic region called the mediastinum o mediastinum is between medial walls of the 2 pleurae o extends from the sternum to the vertebral column, and from first rib to the diaphragm o contains all thoracic organs except the lungs themselves o contains the heart, esophagus, trachea, thymus, and several large blood vessels that enter and leave heart. Pericardium (serous sac) surrounds the heart and contains a small amount of lubricating fluid. Diaphragm is a dome-shaped muscle that separates thoracic cavity from abdominopelvic cavity Abdominopelvic cavity extends from diaphragm to groin is encircled by the abdominal muscle wall and the bones and muscles of the pelvis is divided into two portions, even though no wall separates them o Superior portion = abdominal cavity: contains kidneys, adrenal glands, stomach, spleen, liver, gallbladder, pancreas, small intestine, and most of large intestine. o Inferior portion = pelvic cavity: contains urinary bladder, portions of the large intestine, and internal organs of the reproductive system Organs inside the thoracic and abdominopelvic cavities are termed the viscera Thoracic and Abdominal Cavity Membranes Membrane is a thin pliable tissue that covers, lines, partitions, or connects structures. Serous membrane is a slippery double-layered membrane associated with body cavities that does not open directly to exterior covers viscera within thoracic and abdominal cavities also lines walls of the thorax and abdomen The parts of a serous membrane: o the parietal layer = a thin epithelium that lines walls of the body cavities o the visceral layer = a thin epithelium that covers and adheres to viscera within body cavities. The parietal and visceral membranes are continuous with one another they form a serous sac. organs of the body cavity push into this serous sac, similar to pushing your hand into a balloon Serous cavity between parietal and visceral layers is a potential space contains a small amount of lubricating fluid called serous fluid that reduces friction between two layers allowing viscera to slide freely during movements, such as the pumping of the heart or the inflation and deflation of your lungs when you breathe in and out. Pleura the serous membrane associated with the lungs is called the pleura (Figure 1.7a, c, d). The visceral pleura clings to the surface of the lungs (the part of the balloon touching your fist); the parietal pleura lines the chest wall and covers the superior surface of the diaphragm. In between is the serous cavity called the pleural cavity (analogous to the inside of the balloon), filled with a small volume of lubricating serous fluid. Pericardium The serous membrane of the heart is the pericardium (per_-i-KAR-de¯-um) (see Figure 1.7a, c, d) The visceral pericardium covers the surface of the heart, and the parietal pericardium lines the fibrous pericardium that surrounds the heart. Between them is the serous cavity called the pericardial cavity, which contains a small amount of lubricating serous fluid. Peritoneum is serous membrane of the abdominal cavity visceral peritoneum o covers abdominal viscera parietal peritoneum o lines abdominal wall o covers inferior surface of the diaphragm. peritoneal cavity o between visceral and parietal is this serous cavity o contains a small amount of lubricating serous fluid Most abdominal organs are surrounded by peritoneum o are referred to as intraperitoneal o include stomach, spleen, liver, gallbladder, jejunum and ileum of small intestine, and cecum, appendix, and transverse colon of the large intestine. Some abdominal organs are not surrounded by peritoneum or are only partially covered by peritoneum and lie behind peritoneum. o are referred to as retroperitoneal o include kidneys, adrenal glands, pancreas, duodenum of small intestine, ascending and descending colons of the large intestine, and the abdominal aorta and inferior vena cava Other regional cavities in later chapters: oral (mouth) cavity, which contains the tongue and teeth the nasal cavity in the nose the orbital cavities (orbits), which contain the eyeballs the middle ear cavities (middle ears), which contain small bones and muscles in the middle ear synovial cavities, which are found in freely movable joints and contain synovial fluid 1.6 – ABDOMINOPELVIC REGIONS AND QUADRANTS To describe location of many abdominal and pelvic organs more easily, anatomists and clinicians use two methods of dividing abdominopelvic cavity into smaller areas. FIRST METHOD: Two transverse and two vertical lines, aligned like a tick-tack-toe grid, partition the abdominopelvic cavity into nine abdominopelvic regions (Figure 1.8). The top horizontal line, the subcostal line (sub-_below; costal_rib), is drawn just inferior to the right and left lateral margins of the ribs The bottom horizontal line, the transtubercular line (trans-too-BER-ku¯ -lar), intersects the iliac tubercles, landmarks near the top of the right and left hip bones. Two vertical lines, the left and right midclavicular lines (mid-kla-VIK-u¯ -lar), are drawn through the midpoints of the clavicles (collar bones), just medial to the nipples. The four lines divide the abdominopelvic cavity into a larger middle section and smaller left and right sections. Note which organs and parts of organs are in the different regions The organs of the abdominopelvic cavity will be discussed in detail in later chapters. The names of the nine abdominopelvic regions are: right hypochondriac epigastric left hypochondriac right lumbar umbilical left lumbar right inguinal (iliac) hypogastric (pubic) left inguinal (iliac) SECOND METHOD: divides the abdominopelvic cavity into quadrants a transverse line, the transumbilical line, and a midsagittal line, the median line, are passed through the umbilicus or belly button. The nine-region division is more widely used for anatomical studies to determine organ location quadrants are more commonly used by clinicians for describing the site of abdominopelvic pain, tumor, injury, or other abnormality. The names of the abdominopelvic quadrants are: right upper quadrant (RUQ) left upper quadrant (LUQ) right lower quadrant (RLQ) left lower quadrant (LLQ) 1.7 – THE HUMAN BODY AND DISEASE Disorder = any abnormality of structure and/or function. Disease = a more specific term for an illness characterized by a recognizable set of symptoms and signs in which body structures and functions are altered in characteristic ways. A person w/disease may experience symptoms = subjective changes in body functions that are not apparent to an observer. o Examples: headache, nausea, and anxiety. signs = objective changes that a clinician can observe and measure o can be either anatomical or physiological. An anatomical sign of disease referred to as a lesion (organ or tissue damage resulting from injury or disease) o Examples: swelling, a rash, an ulcer, a wound, or a tumor. A physiological sign of disease fever, high blood pressure, and paralysis. A local disease (such as sinus infection) affects one part or a limited region of body A systemic disease (such as influenza) affects either the entire body or several parts of it. Epidemiology = science that deals with why, when, and where diseases occur and how they are transmitted among individuals in a community Pharmacology = the science that deals with uses and effects of drugs in treatment of disease. Diagnosis = is the science and skill of distinguishing one disorder or disease from another. The patient’s symptoms and signs, his or her medical history, a physical exam, and laboratory tests provide basis for making a diagnosis. Taking a medical history consists of collecting information about events that might be related to a patient’s illness. o These include: chief complaint (primary reason for seeking medical attention) history of present illness past medical problems family medical problems social history review of symptoms and signs. A physical examination = an orderly evaluation of the body and its functions. o This process includes noninvasive techniques: Examples: inspection, palpation, auscultation, and percussion measurement of vital signs (temperature, pulse, respiratory rate, and blood pressure) laboratory tests if necessary 1.8 – MEDICAL IMAGING Medical imaging refers to techniques and processes used to create images of the human body Various types of medical imaging allow visualization of structures inside our bodies and are being used more and more to increase precision of diagnosis of a wide range of anatomical and physiological disorders. Conventional radiography (x-rays) Grandparent of all medical imaging techniques in medical use since late 1940s and still in widespread use today. Newer imaging technologies: improve diagnostic capabilities have advanced our understanding of normal anatomy and physiology. 1.9 – MEASURING THE HUMAN BODY To describe the body and understand how it works you need to use measurement—determination of the dimensions of an organ, its weight, and length of time it takes for a physiological event to occur. Measurements have clinical importance, such as determining dose of a particular medication measurements involving time, weight, temperature, size, and volume are a routine part of medicine The metric system is the standard used in the sciences because it is universal and is based on units of ten (10).