Chapter 7 Anatomy and Physiology

Introduction Anatomy is the study of the structure and makeup of the organism. −Gross anatomy: organs and locations in the body −Microscopic anatomy: visible through microscope Physiology examines the processes and functions of the body.

The Planes of the Body Anatomic planes −Imaginary lines dividing the body −Coronal plane −Transverse plane −Sagittal plane Midsagittal plane −Cross section −Longitudinal section

Directional Terms Needed to discuss: −Where an injury is located −How pain radiates

Movement and Positional Terms Range of motion −Full distance a joint can be moved Flexion −Brings distal point of extremity toward trunk Extension −Returns flexion to anatomic position Abduction −Moves extremity away from midline Adduction −Moves extremity toward midline Hyperflexion −Flexed to or beyond normal range of motion

Movement and Positional Terms Hyperextension −Extended to or beyond normal range of motion Supination −Turning palms upward Pronation −Turning palms downward Internal rotation −Turning extremity toward midline External rotation −Turning extremity away from midline

Other Directional Terms Abdomen is divided into: −Right upper quadrant −Left upper quadrant −Right lower quadrant −Left lower quadrant

Anatomic Positions Prone −Lying face down Supine −Lying face up Trendelenburg position −Supine with feet higher than head Shock position −Head and torso supine, lower extremities elevated Fowler position −Sitting up with knees bent

Anatomic Positions Recovery position −Lying on side, bottom arm extended straight with head lying on it −Top knee is bent, angling body slightly toward floor © Jones & Bartlett Learning. Courtesy of MIEMSS

The Skeletal System: Physiology Bones protect internal organs. With muscles, bones enable movement. Bone stores minerals. −Particularly calcium Plays role in forming blood cells, platelets

The Musculoskeletal System: Anatomy Musculoskeletal system −Provides body’s form, upright posture, movement −Musculoskeletal refers to bones and voluntary muscles of the body. −Protects vital internal organs

The Circulatory System: Anatomy Also called cardiovascular system −Completely closed Two circuits: −Systemic circulation in body −Pulmonary circulation in lungs

The Heart Four chambers: −Two atria −Two ventricles −Each side of the heart contains one atrium and one ventricle. Atria receive blood returned to heart. Ventricles pump blood out of heart.

Blood Flow Within the Heart Deoxygenated blood returns to the right atrium via superior vena cava and inferior vena cava. Freshly oxygenated blood returns to the left atrium through pulmonary veins.

Blood Flow Within the Heart Blood flows through mitral valve into the left ventricle. Left ventricle pumps oxygenated blood into aorta, and then to entire body

The Cardiac Cycle Process that creates the pumping of the heart Systole −Contraction of ventricular mass −Pumping of blood into systemic circulation Diastole −Relaxation phase of cycle

The Vascular System Arteries carry blood away from the heart. Veins carry blood back to the heart. Arteries branch into arterioles. Arterioles divide into capillaries. Capillaries enlarge to form venules. Venules merge to form veins.

The Nervous System: Anatomy and Physiology Perhaps most complex organ system Includes brain, spinal cord, and nerves Responsible for fundamental functions

The Nervous System: Anatomy and Physiology Divided into: −Central nervous system −Peripheral nervous system Somatic nervous system regulates voluntary activities. Autonomic nervous system (ANS) controls involuntary activities.

The Central Nervous System Brain −Controlling organ of body −Main components Cerebrum Cerebellum Brainstem (midbrain, pons, medulla oblongata)

The Central Nervous System Spinal cord −Extension of brainstem −Carries information to and from brain −Contains connections between sensory and motor nerves

The Peripheral Nervous System Divisions: −Somatic nervous system Controls voluntary muscles −Autonomic nervous system Sympathetic nervous system Parasympathetic nervous system

The Peripheral Nervous System Sensory nerves carry information from body to CNS Motor nerves carry information from CNS to muscles Cranial nerves (12 pairs) arise from the base of the brain.

The Peripheral Nervous System Spinal nerves (31 pairs) carry information to and from the CNS from a portion of the body. Nerve plexuses form when nerves exit the spinal cord and follow similar tracts.

Physiology of Sensation Ability to gather and process information about the body and the external environment is important −Generated and transmitted by sensory receptors −Message is processed and: Brought to conscious thought Generates an automatic response (reflex) Discarded as unimportant

General Senses Monitored by receptors in different tissues −Nociceptors monitor pain. −Mechanoreceptors monitor physical properties. −Proprioceptors track position in space. −Baroreceptors measure changes in pressure. −Chemoreceptors measure chemicals in the body.

Special Senses Sense of taste −Taste receptors respond to sweet, salty, sour, and bitter

Special Senses Sense of smell −Upper nasal cavity contains olfactory receptors

Special Senses Sense of sight −Eyeball is the source of information the brain processes into pictures −Image is brought into focus by altering shape and thickness of the lens Distortion of the lens causes difficulty focusing on an object.

Special Senses

Sense of hearing −External ear collects sounds into the ear canal −Sound waves travel through the ear canal to the tympanic membrane or eardrum.

Special Senses Sense of balance −Vestibular system is contained within the inner ear. Composed of fluid-filled sacs (otoliths) and fluid- filled passageways (semicircular canals) Structures are used by the CNS to collect information about movement and orientation.

The Digestive System: Anatomy Digestion: breakdown of foods and the absorption of nutrients Alimentary canal includes: −Mouth −Pharynx −Esophagus −Stomach −Small intestine −Large intestine −Rectum −Anus

The Digestive System: Anatomy Walls of alimentary canal consists of: −Mucosa (carries out secretion and absorption) −Submucosa (carries away absorbed materials) −Muscular layer (provides movement of tube) −Serosa (protects underlying tissues)

The Digestive System: Anatomy

Accessory organs of alimentary canal include: −Teeth −Tongue −Salivary glands −Liver −Gallbladder −Pancreas

The Abdomen Right upper quadrant (RUQ): liver, gallbladder, some of colon and small intestine Left upper quadrant (LUQ): stomach, spleen, some of colon and small intestine Right lower quadrant (RLQ): cecum, ascending colon, appendix Left lower quadrant (LLQ): descending and sigmoid parts of colon

The Abdomen

The Digestive System: Physiology Functions of the digestive system: −Ingestion −Mechanical processing −Digestion −Secretion −Absorption −Excretion

The Digestive System: Physiology In succession, different secretions (primarily enzymes) are added to food by: −Salivary glands −Stomach −Liver −Pancreas −Small intestine

The Digestive System: Physiology Converts food into basic sugars, fatty acids, amino acids −These products cross wall of intestine and travel through portal vein to liver −Liver further processes and stores or transports to heart −Circulatory system then nourishes all cells

The Endocrine System: Anatomy and Physiology Made up of glands located throughout body −Remove, concentrate, or alter materials from blood −Secrete them back into body

The Endocrine System: Anatomy and Physiology Glands secrete proteins called hormones. −Regulate mood, growth and development, tissue function, metabolism, sexual development −Steroid hormone diffuses through cell membrane −Nonsteroidal hormone binds to receptors in cell membrane

The Urinary System: Anatomy and Physiology Controls discharge of waste filtered from blood by kidneys Functions −Controls fluid balance in body −Filters and eliminates wastes −Controls pH balance

The Urinary System: Anatomy and Physiology Components −Kidneys −Ureters −Urinary bladder −Urethra Waste products are constantly filtered from the blood to form urine.

The Urinary System: Anatomy and Physiology Functions of the kidneys: −Reabsorb water as it passes through the system −Secrete erythropoietin −Help activate vitamin D −Help maintain blood volume and pressure