Respiratory

Respiration Equation C 6 H 12 O 6 + 6O 2 = 6CO 2 + 6H 2 O Function of respiratory system: gas exchange. O 2 in / CO 2 out

Pathway of air Nose/mouth--Pharynx--Larynx— Trachea--Bronchi---Bronchioles---Lungs---Alveoli— Capillaries Defenses- Nose-hair traps large particles Trachea, bronchi and bronchioles- all lined with cilia which beat upward to sweep particles away from lungs Mucus moistens air, traps and filters particles. Trachea is covered by epiglottis when swallowing.

Parts of the System Trachea

Lungs

Alveoli Actual site of gas exchange. Network of capillaries surround alveoli. 1 cell thick Pulmonary arteriole Pulmonary venule

Alveoli Each lung has millions of tiny air sacs A series of dead-ends pathways

Diaphragm Large flat muscle under lung. Inhalation- diaphragm moves downward to help increase chest capacity. Decreases pressure so air can flow in. Exhalation- diaphragm relaxes and moves up to push air out. Called NEGATIVE PRESSURE BREATHING

Inhalation and Exhalation

Inhalation Breathing is involuntary Controlled by Medulla oblongata Cells monitors CO2 level Sends nerve impulses to contract diaphragm Increase CO2= increase impulse to breath

Smoking Nicotine increases heart rate and blood pressure Increases CO levels in blood Blocks transport of O2 Leaves tar in lungs Paralyzes cilia Swells respiratory tract