Chapter 1_The Human Body.pdf

Essentials of Human Anatomy & Physiology Thirteenth Edition Global Edition Chapter 1 The Human Body: An Orientation Lectur...

Essentials of Human Anatomy & Physiology Thirteenth Edition Global Edition Chapter 1 The Human Body: An Orientation Lecture Presentation by Patty Bostwick-Taylor Florence-Darlington Technical College Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy (1 of 5) Anatomy – Study of the structure and shape of the body and its parts – Observation is used to see sizes and relationships of parts Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy (2 of 5) Gross anatomy – Large structures – Easily observable Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy (3 of 5) Let’s look at an example of gross anatomy using the digestive system organs Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2i The Body’s Organ Systems (1 of 2) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy (4 of 5) Microscopic anatomy – Structures are too small to be seen with the naked eye – Cells and tissues can be viewed only with a microscope Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy (5 of 5) Let’s look at an example of microscopic anatomy using a digestive system organ, the stomach Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy of the Stomach (1 of 2) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Anatomy of the Stomach (2 of 2) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Physiology (1 of 2) Physiology – Study of how the body and its parts work or function Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Physiology (2 of 2) Structure determines what functions can occur For example, the air sacs of the lungs have very thin walls, a feature that enables them to exchange gases and provide oxygen to the body Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Concept Link Throughout this text, Concept Links will highlight links between concepts and/or organ systems. Keep in mind that although discussions of the systems are separated into chapters for detailed study, the overall goal of this text is for you not only to gain an understanding of each individual system, but also to learn how the body systems interact to sustain life. Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Levels of Structural Organization Six levels of structural organization 1. Atoms 2. Cells 3. Tissues 4. Organs 5. Organ systems 6. Organisms Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (1 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (2 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (3 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (4 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (5 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (6 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.1 Levels of Structural Organization (7 of 7) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (1 of 12) Integumentary system – Forms the external body covering (skin) and includes hair and fingernails – Waterproofs the body – Cushions and protects deeper tissue from injury – Produces vitamin D with the help of sunlight – Excretes salts in perspiration – Helps regulate body temperature – Location of cutaneous nerve receptors Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2a The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (2 of 12) Skeletal system – Consists of bones, cartilages, ligaments, and joints – Provides muscle attachment for movement – Protects vital organs – Site of blood cell formation – Stores minerals Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2b The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (3 of 12) Muscular system – Skeletal muscles contract (or shorten) – Produces movement of bones Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2c The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (4 of 12) Nervous system – Fast-acting control system – Consists of brain, spinal cord, nerves, and sensory receptors – Responds to internal and external stimuli – Sensory receptors detect changes – Messages are sent to the central nervous system – Central nervous system assesses information and activates effectors (muscles and glands) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2d The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (5 of 12) Endocrine system – Secretes chemical molecules, called hormones, into the blood – Body functions controlled by hormones include: ▪ Growth ▪ Reproduction ▪ Use of nutrients Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (6 of 12) Endocrine system – Endocrine glands include: ▪ Pituitary gland ▪ Thyroid and parathyroids ▪ Adrenal glands ▪ Thymus ▪ Pancreas ▪ Pineal gland ▪ Ovaries (females) and testes (males) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2e The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (7 of 12) Cardiovascular system – Includes heart and blood vessels ▪ Heart pumps blood ▪ Vessels transport blood to tissues – Blood transports: ▪ Oxygen and carbon dioxide ▪ Nutrients ▪ Hormones – Blood also contains white blood cells and chemicals that provide protection from foreign invaders Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2f The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (8 of 12) Lymphatic system – Includes lymphatic vessels, lymph nodes, and lymphoid organs – Complements the cardiovascular system by returning leaked fluids back to bloodstream – Lymph nodes and other lymphoid organs cleanse the blood – Houses white blood cells, which are involved in immunity Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2g The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (9 of 12) Respiratory system – Includes the nasal passages, pharynx, larynx, trachea, bronchi, and lungs – Gases are exchanged with the blood through air sacs in the lungs ▪ Supplies the body with oxygen ▪ Removes carbon dioxide Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2h The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (10 of 12) Digestive system – Includes the oral cavity (mouth), esophagus, stomach, small and large intestines, rectum, and accessory organs – Breaks down food – Allows for nutrient absorption into blood – Eliminates indigestible material as feces Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2i The Body’s Organ Systems (2 of 2) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (11 of 12) Urinary system – Includes the kidneys, ureters, urinary bladder, and urethra – Eliminates nitrogenous wastes – Maintains acid-base balance – Regulates water and electrolyte balance – Helps regulate normal blood pressure Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2j The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Organ System Overview (12 of 12) Reproductive system – For males, includes the testes, scrotum, penis, accessory glands, and duct system ▪ Testes produce sperm ▪ Duct system carries sperm to exterior – For females, includes the ovaries, uterine tubes, uterus, and vagina ▪ Ovaries produce eggs ▪ Uterus provides site of development for fetus Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.2k-l The Body’s Organ Systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Maintaining Life: Necessary Life Functions Maintaining boundaries – Boundaries separate the “inside” from the “outside” Movement – Locomotion – Movement of substances Responsiveness (irritability) – Ability to sense changes and react Digestion – Breakdown and absorption of nutrients Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Necessary Life Functions (1 of 2) Metabolism—chemical reactions within the body – Breaks down complex molecules into smaller ones – Builds larger molecules from smaller ones – Produces energy (ATP) – Regulated by hormones Excretion – Eliminates excreta (waste) from metabolic reactions – Wastes may be removed in urine, feces, or sweat Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Necessary Life Functions (2 of 2) Reproduction – Occurs on cellular level or organismal level ▪ On cellular level—new cells are used for growth and repair ▪ On organismal level—the reproductive system handles the task Growth – Increases cell size or body size (through increasing the number of cells) – Hormones play a major role Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Survival Needs (1 of 3) Nutrients – Chemicals used for energy and cell building – Include carbohydrates, proteins, lipids, vitamins, and minerals Oxygen – Required for chemical reactions – Made available by the cooperation of the respiratory and cardiovascular systems Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Survival Needs (2 of 3) Water – 60 to 80 percent of body weight – Most abundant chemical in the human body – Provides fluid base for body secretions and excretions Normal body temperature – 37C (98.6F) – Below this temperature, chemical reactions slow and stop – Above this temperature, chemical reactions proceed too rapidly Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Survival Needs (3 of 3) Atmospheric pressure – Must be appropriate for gas exchange Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.3 Examples of Interrelationships Among Organ Systems That Illustrate Life Functions Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. The Language of Anatomy (1 of 2) Special terminology is used to prevent misunderstanding Exact terms are used for: – Position – Direction – Regions – Structures Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. The Language of Anatomy (2 of 2) Anatomical position – Standard body position used to avoid confusion – Terminology refers to this position regardless of actual body position – Stand erect, feet parallel, arms hanging at the sides with palms facing forward and thumbs pointing away from the body Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.4a The Anatomical Position and Regional Terms (1 of 2) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Directional Terms (1 of 6) Directional terms – Explain location of one body structure in relation to another Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Directional Terms (2 of 6) Superior (cranial or cephalic): toward the head or upper part of a structure or the body; above Inferior (caudal): away from the head or toward the lower part of a structure or the body; below Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Directional Terms (3 of 6) Anterior (ventral): toward or at the front of the body; in front of Posterior (dorsal): toward or at the backside of the body; behind Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Table 1.1 Orientation and Directional Terms (1 of 3) *The term caudal, literally “toward the tail,” is synonymous with inferior only to the inferior end of the spine. †Anterior and ventral are synonymous in humans, but not in four-legged animals. Ventral refers to an animal’s “belly,” making it the inferior surface. Likewise, posterior and dorsal surfaces are the same in humans, but dorsal refers to an animal’s back, making it the superior surface. Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Directional Terms (4 of 6) Medial: toward or at the midline of the body; on the inner side of Lateral: away from the midline of the body; on the outer side of Intermediate: between a more medial and a more lateral structure Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Directional Terms (5 of 6) Proximal: close to the origin of the body part or point of attachment to a limb to the body trunk Distal: farther from the origin of a body part or the point of attachment of a limb to the body trunk Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Table 1.1 Orientation and Directional Terms (2 of 3) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Directional Terms (6 of 6) Superficial (external): toward or at the body surface Deep (internal): away from the body surface; more internal Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Table 1.1 Orientation and Directional Terms (3 of 3) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Regional Terms (1 of 2) Anterior (ventral) body landmarks Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.4a The Anatomical Position and Regional Terms (2 of 2) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Regional Terms (2 of 2) Posterior (dorsal) body landmarks Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.4b The Anatomical Position and Regional Terms Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Planes and Sections (1 of 2) Sections are cuts along imaginary lines known as planes Three types of planes or sections exist as right angles to one another Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Planes and Sections (2 of 2) A sagittal section divides the body (or organ) into left and right parts A median, or midsagittal, section divides the body (or organ) into equal left and right parts A frontal, or coronal, section divides the body (or organ) into anterior and posterior parts A transverse, or cross, section divides the body (or organ) into superior and inferior parts Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.5 The Planes of the Body—Median, Frontal, and Transverse—With Corresponding MRI Scans Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (1 of 7) Two internal body cavities – Dorsal – Ventral Body cavities provide varying degrees of protection to organs within them Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.6 Body Cavities Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (2 of 7) Dorsal body cavity has two subdivisions 1. Cranial cavity ▪ Houses the brain ▪ Protected by the skull 2. Spinal cavity ▪ Houses the spinal cord ▪ Protected by the vertebrae Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (3 of 7) Ventral body cavity has two subdivisions separated by the diaphragm 1. Thoracic cavity 2. Abdominopelvic cavity Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (4 of 7) Thoracic cavity – Cavity superior to the diaphragm – Houses heart, lungs, and other organs – Mediastinum, the central region, houses heart, trachea, and other organs – Protected by the rib cage Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (5 of 7) Abdominopelvic cavity – Cavity inferior to the diaphragm – Superior abdominal cavity contains the stomach, liver, and other organs ▪ Protected only by trunk muscles – Inferior pelvic cavity contains reproductive organs, bladder, and rectum ▪ Protected somewhat by bony pelvis – No physical structure separates abdominal from pelvic cavities Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (6 of 7) Abdominopelvic cavity subdivisions – Four quadrants – Nine regions Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.7 The Four Abdominopelvic Quadrants Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.8 The Nine Abdominopelvic Regions Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Body Cavities (7 of 7) Other body cavities include: – Oral and digestive cavities – Nasal cavity – Orbital cavities – Middle ear cavities Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Homeostasis Homeostasis—maintenance of relatively stable internal conditions – A dynamic state of equilibrium, or balance – Necessary for normal body functioning and to sustain life Main controlling systems – Nervous system – Endocrine system Homeostatic imbalance – A disturbance in homeostasis results in disease Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Maintaining Homeostasis (1 of 2) All homeostatic control mechanisms have at least three components: receptor, control center, and effector – Receptor ▪ Responds to changes in the environment (stimuli) ▪ Sends information to control center along an afferent pathway Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Maintaining Homeostasis (2 of 2) Control center – Determines set point – Analyzes information – Determines appropriate response Effector – Provides a means for response to the stimulus – Information flows from control center to effector along efferent pathway Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Feedback Mechanisms (1 of 2) Negative feedback – Includes most homeostatic control mechanisms – Shuts off the original stimulus or reduces its intensity – Works like a household thermostat Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.9 The Elements of a Homeostatic Control System (1 of 6) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.9 The Elements of a Homeostatic Control System (2 of 6) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.9 The Elements of a Homeostatic Control System (3 of 6) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.9 The Elements of a Homeostatic Control System (4 of 6) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.9 The Elements of a Homeostatic Control System (5 of 6) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Figure 1.9 The Elements of a Homeostatic Control System (6 of 6) Copyright © 2022 Pearson Education, Ltd. All Rights Reserved. Feedback Mechanisms (2 of 2) Positive feedback – Rare in the human body – Increases the original stimulus to push the variable farther – Reaction occurs at a faster rate – In the body, positive feedback occurs in blood clotting and during the birth of a baby Copyright © 2022 Pearson Education, Ltd. All Rights Reserved.