Supplying oxygen to all of the cells of your body Respiratory System Supplying oxygen to all of the cells of your body

Read P.g. 281 Fitness test and design an experiment to calculate your VO2 max. After collect information from your classmates and display the class results in an appropriate format. 1.) Description of your procedure (full experiment you ran) 2.) Class results 3.) Any conclusions you can draw about yourself and the class.

Respiratory System Primary function: Other functions: obtain O2 remove CO2 Other functions: filter air produce sounds sense of smell regulate blood pH

Respiration: All processes involved in the exchange of O2 and CO2 between cells and the environment. Breathing: Movement of gases between external environment and location where they enter and exit the body.

Challenges Larger animals need more O2 for cellular respiration – to produce energy Need a larger surface area for O2 to diffuse across Skin – must be kept moist Gills Spiracles Lungs

Gills Used by many aquatic animals Provide a larger surface area for diffusion on gases

Countercurrent flow P.g. 283-284 – water flows one way, blood in the flows in the opposite direction. Increases efficiency of O2 intake O2-rich blood is in contact with O2-poor water O2 diffuses from a high concentration – low concentration

Spiracles Holes on the outer surface of an animal’s body allow air to pass through for gas exchange Only small animals

Insects: air in spiracles, to a tracheal system. These branching tubes make direct contact with the body cells

Read p.g. 282 -285 Answer practice questions 1-6.

Lungs Huge surface area within the body for gas exchange between the external environment & the blood Thousands of air sacs: alveoli Found in mammals, birds, amphibians, reptiles Higher efficiency for maximum gas exchange

Organs of the Respiratory System Upper respiratory tract: Nose – hair & sticky mucus filter large particles Nasal cavity – hollow space behind nose Pharynx – space behind the nasal cavity, AKA the “throat”

Organs of the Respiratory System Lower respiratory tract: Larynx – between pharynx & trachea, “voice box” Trachea – tube at the front of the neck, “windpipe” Bronchial tree – branched airways connecting the trachea to the air sacs in the lungs Bronchi, bronchioles – passageways in the lungs Lungs – soft, spongy, cone-shaped organs.

Breathing Mechanism Inhalation Exhalation Diaphragm (muscle under the lungs) moves down, pressure in lungs decreases, air enters lungs Exhalation Diaphragm relaxes, ribs & sternum move down & in, pressure in the lungs increases, air is forced out of the lungs Air moves from areas of high pressure to low pressure

Oxygen & CO2 Transport O2 moves from:  the atmosphere  alveoli  blood (dissolves in the plasma & forms bonds with hemoglobin) CO2 is carried away from the body cells in the blood

Bronchitis Ailments characterized by a narrowing of the air passages. Caused by Bacterial or viral infections, or reactions to environmental chemicals.

Read page 294-295 Answer questions 1-3 on page 296. Case study: Smoking and Lung Cancer P.g. 299-301 Analysis questions.