Aim: Respiratory System December 12, 2011 Aim: Respiratory System Warm-up: Why is it better to breathe through your nose than your mouth? HW: No Homework 2008-2009 2008-2009

Structure of the Respiratory System 1) Nose Air is filtered, warmed, and moistened by cilia & mucus 2) Pharynx AKA: Throat oral and nasal cavity meet

3) Larynx Voicebox/ “Adams apple”

Extends from the larynx to the bronchi Trachea 4) Trachea Aka: windpipe Extends from the larynx to the bronchi 5) Bronchi Two major divisions of the trachea Subdivide into bronchioles Bronchi

6) Alveoli Small air sacs Surrounded by capillaries for gas exchange covered by cilia move mucus upward to clear out lungs

Moving gases into bloodstream Inhale O2 passes from alveoli to blood by diffusion Exhale CO2 passes from blood to alveoli by diffusion

Gas exchange: Diffusion of gases The gases move by diffusion from high to low concentration capillaries in lungs capillaries in muscle O2 O2 O2 O2 CO2 CO2 CO2 CO2 blood lungs blood body

Breathing (mammals) Negative pressure breathing air is NOT pushed into lungs during inhale air is pulled into lungs during inhale diaphragm moves down & expands chest cavity pulls air into lungs like suction pump

exhale inhale

Breathing and Homeostasis ATP Need to balance: O2 in and CO2 out Energy (ATP) production Exercise breathe faster need more ATP bring in more O2 & remove more CO2 O2 CO2

Diseases with Respiratory System 1) Bronchitis Infections of air passages in the lungs Can be caused by viruses, bacteria, breathing in certain irritating chemicals

2. Asthma Chronic (long-term) lung disease that inflames and narrows the airways

3. Emphysema A type of lung disease that reduces the ability of the lungs to expel air by damaging alveoli

Healthy Lung vs. Smokers Lung

4. Lung Cancer uncontrolled growth of abnormal cells in one or both of the lungs

Infected lungs Lung Cancer