1. TRANSPORT AND DEFENSE CONTINUED Chapter 12 Lesson 1

2. Essential Questions How do nutrients enter and leave the body? How do nutrients travel through the body? How does the body defend itself from harmful invaders?

3. New Vocabulary Organ System Homeostasis Nutrient Calorie Lymphocyte Immunity

4. The Respiratory System Exchanges gases (oxygen and carbon dioxide) between the body and the environment.  Inhale = air enters the nostrils and passes through the pharynx to the trachea. Diaphragm – muscle under the lungs that relaxes and contracts by inhaling and exhaling. Trachea (windpipe) connects the pharynx to the bronchi.

5. The Respiratory System Bronchi – one enters the right lung and the other enters the left lung.  Bronchi divide into smaller tubes that end in groups of cells calls alveoli.  Alveoli – surrounded by tiny blood vessels called capillaries.

6. The Respiratory System Gas Exchange

7. The Circulatory System The Circulatory System transports nutrients, gases, wastes, and other substances through the body.  It is made up of:  Heart  Blood  Blood Vessels Oxygen in the alveoli enter the capillaries.  The blood inside the capillaries transports oxygen to the rest of the body.

8. The Circulatory System Blood enters the heart though two upper chambers called atria. Blood leaves the heart through the two lower chambers called ventricles. Blood is pumped by the heart’s muscles to the rest of the body.  Blood vessels transport bloods to all organs.

9. The Circulatory System Types of blood vessels:  Arteries – carry oxygen-rich blood away from the heart  Veins – carry oxygen-poor bloods back to the heart  Capillaries – tiny vessels that allow gases and nutrients to move between the blood and the entire body.