BIO 12 UNIT 4: Study Notes

RESPIRATORY SYSTEM PARTS FUNCTIONS

1. Larynx: aka the voice box, vocal chords
2. Trachea: aka the windpipe, tube that carries air towards the lungs and out of the body, C shaped rings strengthen the trachea
3. Bronchi: Tubes divergent from the trachea that lead to the left and right lung, go to each lung
4. Bronchioles: further divisions of bronchi, lead to the alveoli 
5. Alveoli: Hollow cavities found within alveolar sacs, very thin walls allow for gas exchange between CO2 and O2 (exchange between lungs and blood), capillaries are prominent with alveoli allowing for these gases to pass (approx. 3 million alveoli in human lung)
6. Diaphragm: Contracts to aid with inhalation (increases thoracic cavity) or relaxes during exhalation
7. Ribs: Protects lungs, moves up and out during inhalation (increases thoracic cavity), opposite during exhalation
8. Pleural Membranes: Membrane that encloses the lungs, outer pleural membrane sticks to ribs and diaphragm; inner membrane sticks to lungs, allows lungs to move freely without friction, helps lungs inflate (expand)
9. Thoracic Cavity: Contains respiratory organs, "lung cavity", size and pressure effects whether inhalation or exhalation occurs

BIO 12 UNIT 4: Study Notes

VEINS AND ARTERIES FUNCTIONS

1. Subclavian Arteries-- Transports O2ated blood from the aorta to the arms
2. Subclavian Veins-- Transports deO2ated blood from the arms to the heart (RA)
3. Jugular Veins-- Transports deO2ated blood from the head to the Superior Vena Cava
4. Cartoid Arteries-- Transports O2ated from aorta to the head
5. Anterior (Superior) Vena Cava-- Transports deO2ated blood from the jugular vein to the heart (RA) 
6. Posterior (Inferior) Vena Cava-- Transports deO2ated blood from the legs to the heart (RA)
7. Pulmonary Veins-- Transports O2ated blood from the lungs to the heart (LA)
8. Pulmonary Arteries-- Transports deO2ated blood from the heart (RA) to the lungs
9. Hepatic Vein-- Transports deO2ated blood from the liver to the Inferior Vena Cava
10. Hepatic Portal Vein-- Transports deO2ated blood from the intestines to the liver
11. Renal Arteries-- Transports O2ated blood from the aorta to the kidneys
12. Renal Veins-- Transports deO2ated blood from the kidneys to the Inferior Vena Cava 
13. Iliac Arteries-- Transports O2ated blood from the aorta to the legs
14. Iliac Veins-- Transports deO2ated blood from the legs to the Inferior Vena Cava
15. Aorta-- Transports O2ated blood from the heart to the rest of the body
16. Coronary Arteries-- Transports O2ated blood from the aorta to the heart
17. Coronary Veins-- Transports deO2ated blood from the heart muscles to the heart chambers
18. Mesenteric Arteries-- Transports O2ated blood from the aorta to the intestines 

BIO 12 UNIT 4: Study Notes

1. Inferior (Posterior) Vena Cava 
2. Right Ventricle
3. Right Atrium
4. Superior (Anterior) Vena Cava 
5. Aota 
6. Pulmonary Artery
7. Left Atrium
8. Pulmonary Veins
9. Left Ventricle 

BIO 12 UNIT 4: Study Notes

KEY STRUCTURES OF THE CIRCULATORY SYSTEM

BLACK: Systematic Circulation

BLUE: Pulmonary Circulation

• Left Atrium: Sends oxygenated blood to the left ventricle via the AV valve (bicuspid/mitral)
• Right Atrium: Sends deoxygenated blood to the right ventricle via the AV valve (tricuspid)
• Left Ventricle: Sends oxygenated blood via the aortic semi-lunar valve to the aorta which in turn distributes blood throughout the body
• Right Ventricle: Sends deoxygenated blood via the pulmonary semi-lunar valve to the pulmonary trunk to the pulmonary arteries--> lungs (gas exchange)
• Coronary Arteries and Veins: Part of systematic circuit that are the initial branches off the aorta. Cardiac veins empty into the right atrium (capillary beds (exterior)--> venules--> veins)
• Anterior (Superior) Vena Cava: Sends deoxygenated blood from the upper body (head, chest and arms) to the heart (right atrium)
• Posterior (Inferior) Vena Cava: Sends deoxygenated blood from the lower body (liver, kidneys, intetsines, feet, etc.) to the heart (right atrium)
• Aorta: Sends oxygenated blood throughout the body (organs, tissues, etc.); starts near left ventricle 
• Pulmonary Arteries: Sends deoxygenated blood from the heart to the lungs for gas exchange (stems from pulmonary trunk that stems from the right ventricle)
• Pulmonary Veins: Sends oxygenated blood to the heart (left atrium) from the lungs 
• Pulmonary Trunk: Stems from right ventricle and carries deoxygenated blood from the heart to the pulmonary arteries that carry it the lungs
• Atrioventricular Valves: Located in between the atrium and ventricle for each side of the heart, allows blood into the ventricle and prevents backflow of blood back into the atria
• RA/RV= Tricuspid AV valve
• LA/LV= Bicuspid/Mitral AV valve
• Chordae Tendineae: Strong fibrous strings that prevent invertion of AV valves (blood goes to wrong chambers)
• Semi-Lunar Valves: Half-moon shaped structures located in between the ventricle and corresponding vessel; prevents backflow of blood back into the ventricle
• Pulmonary: In between the RV and the pulmonary trunk
• Aortic: In between LV and the aorta
• Septum: Separates left from right side of the heart, composed of muscular tissue 

BIO 12 UNIT 4: Study Notes

CO2 & H2 IONS AND MEDULLA OBLONGATA STIMULATION

• Increasing concentrations of carbon dioxide and hydrogen ions is detected by the respiration control centre at the brain (medulla oblongata) which in turn will INCREASE the rate of breathing 

BIO 12 UNIT 4: Study Notes

INHALATION AND EXHALATION & BREATHING INTERACTIONS

• INHALATION: Entrance of air into the lungs
• Active
• Controlled by medulla oblongata in the brain--> sends nerve impulses to the diaphragm and ribs
• Lungs expand (inflate)
• Pleural membranes stretch (allows lungs to freely expand)
• Intercostal rib muscles contract to move ribs up and out
• Ribs move up and out increasing thoracic cavity size and decreasing pressure (lower than atmospheric [air] pressure: high (in external air) to low (in body lungs))--> air enters body
• Diaphragm contracts to increase thoracic cavity size and decrease pressure 
• Thoracic Cavity size INCREASES 
• Thoracic Cavity pressure DECREASES 
• EXHALATION: Exit of air from the lungs
• Passive
• Lungs compress (deflate)
• Pleural membranes relax (constricts lung expansion)
• Intercostal rib muscles relax to move ribs in and down
• Ribs move down and in decreasing thoracic cavity size, increases thoracic cavity pressure (higher than atmospheric [air] pressure: high (in body lungs) to low (external air))--> air leaves body
• Diaphragm relaxes to decrease thoracic cavity size and increase pressure
• Thoracic Cavity size DECREASES 
• Thoracic Cavity pressure INCREASES 

VIDEO: :)

http://www.youtube.com/watch?v=HiT621PrrO0&feature=related

BIO 12 UNIT 4: Study Notes

CILIA AND MUCUS IN RESPIRATION

• Found in trachea

• MUCUS: traps debris in the lungs (dust)

• CILIA: sweeps mucus towards the throat, out of trachea