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| Prologue | |
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| An Introduction to the Human Body | |
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| The human body is composed of six levels of structural organization and contains eleven organ systems | |
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| The human body carries on basic life processes that distinguish it from nonliving objects. | |
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| Homeostasis is controlled through feedback systems | |
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| The human body is described using the anatomical position and specific terms | |
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| Body cavities are spaces within the body that help protect, separate, and support internal organs. | |
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| Serous membranes line the walls of body cavities and cover the organs within them. | |
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| The abdominopelvic cavity is divided into regions or quadrants | |
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| The Chemical Level of Organization | |
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| Chemical elements are composed of small units called atoms | |
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| Atoms are held together by chemical bonds | |
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| Chemical reactions occur when atoms combine with or separate from other atoms | |
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| Inorganic compounds include water, salts, acids, and bases | |
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| Organic molecules are large carbon-based molecules that carry out complex functions in living systems | |
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| Carbohydrates function as building blocks and sources of energy | |
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| Lipids are important for cell membrane structure, energy storage, and hormone production | |
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| Proteins are amino acid complexes serving many diverse roles | |
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| Nucleic acids contain genetic material and function in protein synthesis | |
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| Adenosine triphosphate (ATP) is the principal energy-transferring molecule in living systems | |
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| The Cellular Level of Organization | |
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| The principal Parts of a cell are the plasma membrane, the cytoplasm, and the nucleus | |
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| The plasma membrane contains the cytoplasm and regulates exchanges with the extracellular environment | |
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| Transport of a substance across the plasma membrane occurs by both passive and active processes | |
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| Cytoplasm consists of the cytosol and organelles | |
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| The nucleus contains nucleoli and genes | |
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| Cells make proteins by transcribing and translating the genetic information contained in DNA | |
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| Cell division allows the replacement of cells and the production of new cells | |
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| The Tissue Level of Organization | |
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| Human body tissues can be classified as epithelial, connective, muscle, or nervous | |
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| Epithelial tissue covers body surfaces, lines organs and body cavities, or secretes substances | |
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| Connective tissue binds organs together, stores energy reserves as fat, and helps provide immunity | |
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| Membranes cover the surface of the body, line body cavities, and cover organs | |
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| Muscle tissue generates the physical force needed to make body structures move | |
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| Nervous tissue consists of neurons and neuroglia | |
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| The ability of an injured tissue to repair itself depends on the extent of damage and the regenerative ability of the injured tissue | |
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| Body Systems | |
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| The Integumentary System | |
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| Skin is composed of a superficial epidermis and a deeper dermis, and is anchored by the hypodermis | |
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| The layers of the epidermis include the stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum | |
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| The dermis contains blood vessels, lymphatic vessels, nerves, sensory receptors, hair follicles, and glands | |
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| Skin color is a result of the pigments melanin, carotene, and hemoglobin | |
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| The functions of hair, skin glands, and nails include protection and body temperature regulation | |
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| Skin damage sets in motion a sequence of events that repairs the skin to its normal | |
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| Skin regulates body temperature, protects underlying tissues, provides cutaneous sensations, excretes body wastes, and synthesizes vitamin D | |
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| Introduction to the Skeletal System | |
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| Skeletal system functions include support, protection, movement, mineral homeostasis, blood cell production, and energy storage | |
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| Bones are classified as long, short, flat, irregular, or sesamoid | |
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| Long bones have a diaphysis, a medullary cavity, epiphyses, metaphyses, and periosteum | |
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| Osseous tissue can be arranged as compact bone tissue or spongy bone tissue | |
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| Bones are richly supplied with blood vessels and nerves | |
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| The two types of bone formation are intramembranous ossification and endochondral ossification | |
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| Bones grow longer due to activity of the epiphyseal plate and increase in diameter by the addition of new osseous tissue around the outer surface | |
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| Bone remodeling renews osseous tissue, redistributes bone extracellular matrix, and repairs bone injuries | |
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| The Axial Skeleton | |
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| Bones of the axial skeleton and appendicular skeleton have characteristic surface markings | |
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| The skull provides attachment sites for muscles and membranes, and protects and supports the brain and sense organs | |
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| The cranial bones include the frontal, parietal, temporal, occipital, sphenoid, and ethmoid bones | |
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| Facial bones include the nasal bones, maxillae, zygomatic bones, mandible, lacrimal bones, palatine bones, inferior nasal conchae, and vomer | |
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| Unique features of the skull include the nasal septum, orbits, sutures, paranasal sinuses, and fontanels | |
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| The hyoid bone supports the tongue and attaches to tongue, pharynx, and larynx muscles | |
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| The vertebral column encloses and protects the spinal cord, supports the head, and is a point of attachment for the ribs, pelvic girdle, and muscles of the back | |
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| A vertebra usually consists of a body, a vertebral arch, and several processes | |
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| Vertebrae in the different regions of the vertebral column vary in size, shape, nd detail | |
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| The thoracic cage encloses and protects vital organs in the thorax and upper abdomen and provides support for the bones of the shoulder girdles and upper limbs | |
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| The Appendicular Skeleton | |
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| Each pectoral girdle, which consists of a clavicle and scapula, attaches an upper limb to the axial skeleton | |
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| The bones of each upper limb include the humerus, ulna, radius, carpals, metacarpals, and phalanges | |
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| The pelvic girdle supports the vertebral column and pelvic viscera and attaches the lower limbs to the axial skeleton | |
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| Male pelves are generally larger, heavier, and have more prominent markings; female pelves are generally wider and shallower | |
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| The bones of each lower limb include the femur, patella, tibia, fibula, tarsals, metatarsals, and phalanges | |
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| Articulations | |
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| Joints are classified structurally as fibrous, cartilaginous, or synovial; they are classified functionally as synarthroses, amphiarthroses, or diarthroses | |
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| Fibrous joints lack a synovial cavity and are held together by fibrous connective tissue | |
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| Cartilaginous joints lack a synovial cavity and are held together by cartilage | |
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| Articulating surfaces of bones at a synovial joint are covered with articular cartilage and enclosed within a synovial cavity | |
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| Synovial joints are described as planar, hinge, pivot, condyloid, saddle, or ball-and-socket | |
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| Synovial joint movement terminology indicates the direction of movement or the relationships of body Parts during movement | |
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| The shoulder, elbow, hip, and knee joints provide examples of synovial joint components, classifications, and movements | |
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| Muscle Tissue | |
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| Skeletal, cardiac, and smooth muscle tissues differ in location, structure, and function | |
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| Muscle tissue produces movement, generates heat, and stabilizes body positions; it possesses electrical excitability, contractility, extensibility, and elasticity | |
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| Skeletal muscles are surrounded by connective tissues and are well supplied with nerves and blood vessels | |
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| Each skeletal muscle fiber is covered by a sarcolemma; each of its myofibrils is surrounded by sarcoplasmic reticulum and contains sarcomeres | |
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| The neuromuscular junction is where a muscle action potential is initiated | |
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| An action potential releases calcium ions that allow thick filaments to bind to and pull thin filaments toward the center of the sarcomere | |
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| Muscle fiber tension is controlled by stimulation frequency and the number of motor units activated; changes in tension can produce isotonic or isometric contractions | |
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| Muscle fibers produce ATP from creatine phosphate, by anaerobic cellular respiration, and by aerobic cellular respiration | |
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| Skeletal muscle fibers are classified as slow oxidative fibers, fast oxidative-glycolytic fibers, or fast glycolytic fibers | |
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| Cardiac muscle tissue is found in the walls of the heart, and smooth muscle tissue is found in the walls of hollow organs, blood vessels, and airways | |
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| The Muscular System | |
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| Skeletal muscles produce movement when the insertion is pulled toward the origin | |
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| Skeletal muscles are named based on size, shape, action, location, or attachments | |
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| Muscles of the head produce facial expressions, eyeball movement, and assist in biting, chewing, swallowing, and speech | |
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| Muscles of the neck assist in swallowing and speech, and allow balance and movement of the head | |
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| Muscles of the torso help protect the abdominal viscera, move the vertebral column, and assist breathing | |
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| Muscles of the pelvic floor and perineum support the pelvic viscera, function as sphincters, and assist in urination, erection, ejaculation, and defecation | |
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| Muscles inserting on the upper limb move and stabilize the pectoral girdle, and move the arm, forearm, and hand | |
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| Deep muscles of the back move the head and vertebral column | |
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| Muscles originating on the pelvic girdle or lower limb move the femur, leg, and foot | |
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| Introduction to the Nervous System | |
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| The nervous system maintains homeostasis and integrates all body activities | |
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| The nervous system is organized into the central and peripheral nervous systems | |
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| Neurons are responsible for most of the unique functions of the nervous system | |
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| Neuroglia support, nourish, and protect neurons and maintain homeostasis | |
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| Neurons communicate with other cells | |
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| Graded potentials are the first response of a neuron to stimulation | |
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| The action potential is an all-or-none electrical signal | |
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| Action potentials propagate from the trigger zone to axon terminals | |
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| The synapse is a special junction between neurons | |
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| PNS neurons have a greater capacity for repair and regeneration than CNS neurons | |
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| The Central Nervous System | |
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| The CNS consists of the brain, the spinal cord, and several protective structures | |
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| The CNS is nourished by blood and cerebrospinal fluid, which also provides mechanical and chemical protection | |
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| The cerebrum interprets sensory impulses, controls muscular movements, and functions in intellectual processes | |
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| The limbic system controls emotions, behavior, and memory | |
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| The cerebral cortex can be divided functionally into sensory areas, motor areas, and association areas | |
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| The diencephalon includes the thalamus and the hypothalamus | |
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| The midbrain, pons, and medulla oblongata of the brain stem serve as a relay station and control center | |
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| The cerebellum coordinates movements and helps maintain normal muscle tone, posture, and balance | |
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| The spinal cord gray matter receives sensory input and provides motor output through spinal nerves | |
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| The spinal cord conducts nerve impulses between spinal nerves and the brain, and contains reflex pathways | |
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| The Peripheral Nervous System | |
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| Nerves have three protective connective tissue coverings | |
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| Twelve pairs of cranial nerves distribute primarily to regions of the head and neck | |
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| Each spinal nerve branches into a posterior ramus, anterior ramus, meningeal branch, and rami communicantes | |
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| A reflex is produced by a reflex arc in response to a Particular stimulus | |
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| The autonomic nervous system produces involuntary movements | |
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| The ANS includes preganglionic neurons, autonomic ganglia and plexuses, and postganglionic neurons | |
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| ANS neurons release acetylcholine or norepinephrine, resulting in excitation or inhibition | |
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| The sympathetic division supports vigorous physical activity; the parasym pathetic division conserves body energy | |
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| Autonomic reflexes regulate controlled body conditions and are primarily integrated by the hypothalamus | |
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| Sensory, Motor, and Integrative Systems | |
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| Sensations arise as a result of stimulation, transduction, generation, and integration | |
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| Sensory receptors can be classified structurally, functionally, or by the type of stimulus detected | |
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| Somatic sensations include tactile sensations, thermal sensations, pain, and proprioception | |
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| The somatosensory and primary motor areas of the cerebral cortex unequally serve different body regions | |
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| Somatic sensory pathways relay information from sensory receptors to the cerebral cortex and cerebellum | |
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| Somatic motor pathways carry impulses from the brain to effectors | |
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| Wafefulness and memory are integrative functions of the brain | |
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| The Special Senses | |
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| Impulses for smell propagate along the olfactory nerve to the brain | |
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| Impulses for taste propagate along the facial, glossopharyngeal, and vagus nerves to the brain | |
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| The eye is protected by eyelids, eyelashes, eyebrows, and a lacrimal apparatus | |
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| The eye is constructed of three layers and two chambers | |
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| Image formation involves refraction of light rays, change in lens shape, and constriction of the pupil | |
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| The neural pathway for light is photoreceptors → ganglion cells → optic nerve → primary visual cortex | |
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| The three main regions of the ear are the external, middle, and internal ear | |
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| The pathway of sound is tympanic membrane → ossicles → oval window → cochlea → vestibulocochlear nerve → primary auditory cortex | |
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| Impulses for equilibrium propagate along the vestibulocochlear nerve to the brain | |
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| The Endocrine System | |
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| The endocrine system works more slowly than the nervous system, releasing hormones into the blood that can control virtually all body cells | |
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| The secretion of hormones is regulated by signals from the nervous system, chemical changes in the blood, and other hormones | |
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| The hypothalamus regulates anterior pituitary hormone secretion of seven important hormones | |
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| Oxytocin and antidiuretic hormone originate in the hypothalamus and are stored in the posterior pituitary | |
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| The thyroid gland secretes the thyroid hormones thyroxine, triiodothyronine, and calcitonin | |
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| The parathyroid glands secrete parathyroid hormone, which regulates calcium, magnesium, and phosphate ion levels | |
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| The adrenal cortex secretes mineralocorticoids, glucocorticoids, and androgens; the adrenal medulla secretes epinephrine and norepinephrine | |
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| The pancreatic islets regulate blood glucose levels by secreting glucagon and insulin | |
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| The ovaries produce estrogens, progesterone, and inhibin; the testes produce testosterone and inhibin | |
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| The pineal gland secretes melatonin, which contributes to setting the body's biological clock | |
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| The Cardiovascular System: The Blood | |
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| Blood contains plasma and formed elements and transports essential substances through the body | |
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| Hemopoiesis is the production of formed elements | |
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| Mature red blood cells are biconcave cells containing hemoglobin | |
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| Red blood cells have a life cycle of 120 days | |
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| Erythropoiesis is the process of red blood cell formation | |
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| Blood is categorized into groups based on surface antigens | |
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| White blood cells combat inflammation and infection | |
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| Platelets reduce blood loss from damaged vessels | |
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| Hemostasis is the sequence of events that stops bleeding from a damaged blood vessel | |
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| The Cardiovascular System: The Heart | |
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| The heart is located in the mediastinum and has a muscular wall covered by pericardium | |
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| The heart has four chambers, two upper atria and two lower ventricles | |
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| Heart valves ensure one-way flow of blood | |
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| The heart pumps blood to the lungs for oxygenation, then pumps oxygen-rich blood throughout the body | |
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| The cardiac conduction system coordinates heart contractions for effective pumping | |
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| The electrocardiogram is a record of electrical activity associated with each heartbeat | |
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| The cardiac cycle represents all the events associated with one heartbeat | |
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| Cardiac output is the blood volume ejected by a ventricle each minute | |
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| The Cardiovascular System: Blood Vessels | |
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| Most blood vessel walls have three distinct tissue layers | |
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| Blood ejected from the heart flows through elastic arteries, muscular arteries, and then arterioles | |
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| Capillaries are microscopic blood vessels that function in exchange between blood and interstitial fluid | |
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| Venules and veins return blood to the heart | |
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| Blood flow occurs from regions of higher pressure to those of lower pressure | |
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| Blood pressure is regulated by neural and hormonal negative feedback systems | |
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| Measurement of the pulse and blood pressure are two ways to assess the functioning of the cardiovascular system | |
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| The two main circulatory routes are the pulmonary circulation and the systemic circulation | |
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| Systemic arteries carry blood from the heart to all body organs except the lungs | |
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| Systemic veins return blood to the heart from all body organs except the lungs | |
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| The Lymphatic System and Immunity | |
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| The lymphatic system drains interstitial fluid, transports dietary lipids, and protects against invasion | |
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| Lymph flows through lymphatic capillaries, lymphatic vessels, and lymph nodes | |
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| The lymphatic organs and tissues include the thymus, lymph nodes, spleen, and lymphatic nodules | |
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| Innate immunity includes external physical and chemical barriers and various internal defenses | |
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| Adaptive immunity involves the production of a specific lymphocyte or antibody against a specific antigen | |
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| In cell-mediated immunity cytotoxic T cells directly attack target cells | |
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| In antibody-mediated immunity, antibodies specifically target a Particular antigen | |
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| The complement system destroys microbes through phagocytosis, cytolysis, and inflammation | |
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| Immunological memory results in a more intense secondary response to an antigen | |
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| The Respiratory System | |
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| Inhaled air travels in the upper respiratory system through the nasal cavities of the nose and then through the pharynx | |
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| Inhaled air travels in the lower respiratory system from the larynx to alveoli | |
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| Inhalation and exhalation result from pressure changes caused by muscle contraction and relaxation | |
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| Important measurements of lung volumes and capacities include tidal volume, inspiratory reserve volume, expiratory reserve volume, residual volume, and lung capacities | |
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| Oxygen and carbon dioxide diffuse into or out of the blood based on Partial pressure gradients and solubility | |
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| Respiration occurs between alveoli and pulmonary blood capillaries and between systemic blood capillaries and tissue cells | |
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| Oxygen is primarily transported attached to hemoglobin, while carbon dioxide is transported in three different ways | |
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| The basic rhythm of respiration is controlled by the respiratory center in the brain stem | |
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| Respiration may be modified by cortical influences, chemical stimuli, proprioceptor input; and the inflation reflex | |
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| The overall acid-base balance of the body is maintained by controlling the H+ concentration of body fluids | |
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| The Digestive System | |
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| The GI tract is a continuous multilayered tube extending from the mouth to the anus | |
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| The mouth lubricates and begins digestion of food, and maneuvers it to the pharynx for swallowing | |
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| Swallowing consists of voluntary oral, involuntary pharyngeal, and involuntary esophageal stages | |
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| The stomach mechanically breaks down the bolus and mixes it with gastric secretions | |
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| The pancreas secretes pancreatic juice, the liver secretes bile, and the gallbladder stores and concentrates bile | |
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| In the small intestine, chyme mixes with digestive juices from the small intestine, pancreas, and liver | |
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| In the large intestine, the final secretion and absorption of nutrients occur as chyme moves toward the rectum | |
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| Digestive activities occur in three overlapping phases: cephalic, gastric, and intestinal | |
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| Food molecules supply energy for life processes and serve as building blocks for complex molecules | |
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| Metabolism includes the catabolism and anabolism of molecules | |
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| The Urinary System | |
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| The kidneys regulate the composition of the blood, produce hormones, and excrete wastes and foreign substances | |
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| After blood is filtered in the renal cortex, the resulting urine travels through the renal medulla, calyces, and renal pelvis | |
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| Each of the nephrons consists of a renal corpuscle and a renal tubule | |
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| The functions of the nephrons and collecting ducts are glomerular filtration, tubular secretion, and tubular reabsorption | |
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| Unlike other components of the blood, water and solutes easily pass through the filtration membrane during glomerular filtration | |
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| Tubular reabsorption reclaims substances from the filtrate, while tubular secretion discharges substances not needed by the body | |
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| Four hormones regulate tubular reabsorption and tubular secretion | |
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| Antidiuretic hormone affects the concentration of urine produced by the kidneys | |
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| The ureters transport urine from the renal pelvis to the urinary bladder where it is stored until micturition | |
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| The kidneys help maintain the overall fluid and acid-base balance of the body | |
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| The Reproductive Systems and Development | |
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| The scrotum supports and regulates the temperature of the testes, which produce spermatozoa | |
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| Sperm are transported from the testes through the epididymis, ductus deferens, ejaculatory ducts, and urethra | |
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| After a secondary oocyte is discharged from an ovary, it may undergo fertilization and implantation in the uterus | |
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| The vagina is a passageway for childbirth; the mammary glands secrete milk | |
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| The female reproductive cycle includes the ovarian and uterine cycles | |
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| The zygote divides into a morula and then a blastocyst that implants in the endometrium of the uterus | |
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| During the embryonic period, the embryonic membranes and most major organs develop | |
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| During pregnancy the uterus expands, maternal gastrointestinal tract organs are displaced, and the ureters and urinary bladder are compressed | |
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| Labor includes dilation of the cervix and expulsion of the fetus and placenta | |
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| Milk production and ejection are influenced by prolactin, estrogens, progesterone, and oxytocin | |
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| Epilogue | |
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| Appendices | |
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| Glossary | |
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| Index | |