The Respiratory System The respiratory system functions to bring oxygen into the body & remove carbon dioxide

Composition of Air GAS N2 O2 Ar CO2 INHALED EXHALED 78 % 21 % ~ 1 % 0.03 % ~ 1 % 5 % 78 % 16 %

RESPIRATORY SYSTEM A J B K L C M D N E O F G P H Q I

1. Breathing Inhalation Diaphragm contracts (it flattens and moves downwards) Intercostal muscles contract to move rib cage up and out Thoracic cavity enlarges pressure in lungs decreases air is sucked into lungs by the air pressure difference

Pathway for air inhaled Nasal cavity or mouth Pharynx Larynx and vocal cords Trachea Bronchi Bronchioles Alveoli

Exhalation diaphragm relaxes and moves upwards intercostal muscles relax to move rib cage down and in volume of thoracic cavity decreases pressure in lungs increases air is pushed out

Pathway for air exhaled Nasal cavity or mouth Pharynx Larynx and vocal cords Trachea Bronchi Bronchioles Alveoli

2. Air Processing Blood Vessels Air is warmed to body temperature

Cilia small hairs lining nasal cavity and airways ‘sweep’ debris & dirty mucous up trachea for disposal by coughing, swallowing, or spitting

Mucous Coats cilia & lung tissue Traps dust and bacteria allows gases to dissolve so they can diffuse through membranes

3. Gas Exchange External Respiration oxygen diffuses from alveoli into blood oxygen binds to hemoglobin and is carried by red blood cells carbon dioxide diffuses from blood into alveoli

Internal Respiration oxygen diffuses out of blood into extra-cellular fluid, then into cells carbon dioxide diffuses out of cells, into extra-cellular fluid, then into blood carbon dioxide is carried in blood plasma as a dissolved gas

4. Cellular Respiration occurs in the mitochondria breakdown of glucose to produce ATP requires large amounts of oxygen produces carbon dioxide

5. Regulation of Breathing [CO2] in blood rises blood pH falls carotid artery sensors detect low pH medulla oblongata signals diaphragm and intercostal muscles to relax production of CO2 by cells [CO2] in blood falls CO2 expelled

ACIDITY OF THE RESPIRATORY SYSTEM CO2 + H2O  H2CO3  H+ + HCO3- carbonic acid hydrogen ion and bicarbonate ion

Math of breathing Purpose: To calculate how much O2 is used by an organism in a given amount of time. Comparisons: In order to compare animals of different sizes, the calculations must be done on a per kilogram basis

Formula: O2 inhaled per hour per kilogram = breathes per hour X volume per breathe X percent of air that is oxygen _________________________________________________________ mass in kilograms

Example: How much oxygen does a 72 kg person inhale per hour if they have a tidal volume of 0.82 L and breathe 17 times per minute? [17 br/min X 60 min/h] X 0.82 L/br X 21% O2 ________________________________________ O2 inhaled = 72 kg 1020 br/h X 0.82 L/br X 0.21 O2 72 kg O2 inhaled = O2 inhaled = 2.4395 L/h/kg The man inhales 2.43 LO2/h/kg

Another Example: A 53 kg woman breathes 18 800 times per day and has a tidal volume of 0.67 L. What is her volume of oxygen inhaled per hour on a per kilogram basis? [18 800 br/day / 24h/day] X 0.67L/br X 21% O2 _______________________________________ O2 inhaled = 53 kg 783.3333 br/h X 0.67 L/br X 0.21 O2 53 kg O2 inhaled = O2 inhaled = 2.0795 L/h/kg The woman inhaled 2.08 LO2/h/kg

IRV, TV, RV, ERV, VC, IC, FRV, TLC Respiration Chart TERMS IRV, TV, RV, ERV, VC, IC, FRV, TLC

Voice Production Voice production occurs by forcing air through connective tissue at the point of the larynx during exhalation

Assignment pg 23 Procedure 1- 5 Questions 1 - 4