RESPIRATORY SYTEM ANATOMY PHYSIOLOGY BACKGROUNDCELLULAR RESPIRATION OXYGEN IS

RESPIRATORY SYTEM ANATOMY & PHYSIOLOGY

BACKGROUND-CELLULAR RESPIRATION • OXYGEN IS USED BY CELLS • OXYGEN IS NEEDED TO CONVERT GLUCOSE TO ATP • CARBON DIOXIDE IS A WASTE PRODUCT • BODY CELLS DIE IF RESPIRATION FAILS

FUNCTIONS • SUPPLIES BODY WITH OXYGEN AND REMOVES CARBON DIOXIDE • FILTERS, WARMS, AND HUMIDIFIES AIR • HELPS WITH PRODUCING SOUND • REGULATES BLOOD PH

DIVISIONS OF THE RESPIRATORY SYSTEM • UPPER RESPIRATORY TRACT • NOSE/NASAL CAVITY • SINUSES/PHARYNX/LARYNX • LOWER RESPIRATORY TRACT • TRACHEA/BRONCHIAL TREE/LUNGS

STRUCTURES/ORGANS • CONDUCTING ZONE- PASSAGES THAT LET AIR IN • RESPIRATORY ZONE- GAS EXCHANGE • LARYNX- VOICE BOX; MADE OF CARTILAGE • FALSE AND TRUE VOCAL CORDS • ATTACHED TO HYOID BONE • SPEECH • BREATHING AIRWAY • SWITCHING MECHANISM FOR FOOD AND AIR→ EPIGLOTTIS

STRUCTURES/ORGANS • TRACHEA- WINDPIPE; SMOOTH CARTILAGE WITH C SHAPED RINGS THAT DIVIDES INTO 2 BRONCHI; FLEXIBLE BUT DOES NOT COLLAPSE DESPITE PRESSURE CHANGES • BRONCHI- TUBES ENTER LUNGS; BRANCH INTO MICROSCOPIC ALVEOLAR DUCTS THAT END IN SACS • LUNGS- EXTEND FROM DIAPHRAGM TO CLAVICLE; LOBES (2 LEFT LOBS AND 3 RIGHT LOBES) • ALVEOLI- SITE OF GAS EXCHANGE

STRUCTURES/ORGANS • NOSE- AIRWAY; MOISTEN AND WARMS AIR; FILTERS; RESONATING CHAMBER FOR SPEECH; OLFACTORY RECEPTORS; NASAL CAVITY=FLOOR=PALATE (ANTERIOR IS HARD AND POSTERIOR IS SOFT) • PARANASAL SINUS- OPEN INTO NASAL; LIGHTEN THE SKULL • INFECTION=SINUSITIS • PHARYNX- THROAT; HOUSES TONSILS • 3 PARTS (NASO, ORO, LARYNGO) • UVULA CLOSES NASOPHARYNX (NO FOOD IN THE NOSE)

RESPIRATORY MUCOSA • GOBLET CELLS • SECRETE MUCUS • WATERY FLUID WITH LYSOZYMES • PRODUCE ABOUT A QUART A DAY OF LIQUID WITH CELL DEBRIS

GAS EXCHANGE • AIR FILLS ALVEOLI AND ACCOUNTS FOR MOST OF THE LUNG VOLUME (1500 SQ FEET) • WALL OF ALVEOLI→ 2 CELLS THICK (THINNER THAN TISSUE PAPER); EXTERNAL WALL IS COVERED WITH COBWEB OF CAPILLARIES

GAS EXCHANGE PT. 2 • AIR/BLOOD BARRIER- GAS EXCHANGE; OXYGEN DIFFUSES FROM AIR IN ALVEOLI TO BLOOD IN CAPILLARIES; CARBON DIOXIDE DIFFUSES FROM BLOOD (CAPILLARIES) INTO ALVEOLI • MOVES FROM A HIGH TO LOW CONCENTRATION THROUGH DIFFUSION

RESPIRATION INCLUDES: • PULMONARY VENTILATION- REPLACES GASES • EXTERNAL RESPIRATION- GAS EXCHANGE IN THE LUNGS • TRANSPORT- GASES BY THE BLOOD AND HEART • INTERNAL RESPIRATION- GAS EXCHANGE INTO THE TISSUES

VENTILATION • BREATHING IS PULMONARY VENTILATION 2 PHASES • INSPIRATION- INHALATION OF AIR/AIR GOES IN • DIAPHRAGM FLATTENS WHEN CONTRACTED (HIGH HEIGHT OF THORACIC CAVITY) • INTERCOSTAL MUSCLES CONTRACT TO RAISE THE RIBS (INCREASES CIRCUMFERENCE OF THE THORACIC

VENTILATION PT. 2 • EXPIRATION- EXHALATION OF AIR/AIR GOES OUT • RIB CAGE DROPS UNDER THE FORCE OF GRAVITY • RELAXED DIAPHRAGM → MOVES UP (CURVED SHAPE) • VOLUME DECREASES WHICH INCREASES THE PRESSURE

VENTILATION PT. 3 • MECHANICAL FORCES CAUSES MOVEMENT OF AIR • GASES FLOW FROM HIGH TO LOW PRESSURE • DIAPHRAGM AND INTERCOSTAL MUSCLES ACCOMPLISH THIS • PRESSURE IS ESTABLISHED BY CHANGES IN THE THORACIC CAVITY • HIGH (SIZE) THORAX → LOW PRESSURE = AIR MOVES IN • LOW (SIZE) THORAX → HIGH PRESSURE = AIR MOVES OUT

VOLUMES OF AIR EXCHANGE • VITAL CAPACITY: LARGEST VOLUME OF AIR A PERSON CAN MOVE IN AND OUT • DEPENDS ON THE SIZE OF THE CAVITY, POSTURE, DISEASES/CONDITION