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

BIO 12 UNIT 4: Study Notes

FORMED ELEMENTS

1. RED BLOOD CELLS:
1. aka Erythrocytes (red-purple biconcave desks, no nuclei)
2. Come from red bone marrow
3. Transports O2 and CO2
4. Hemoglobin (red part) allows it to acquire O2 (lungs) and release it (tissues)
2. WHITE BLOOD CELLS:
1. aka Leukocytes 
2. Larger, have nucleus, translucent 
3. Come from red bone marrow
4. Fights infection
1. Neutrophils (55 to 70%): spherical, multiple lobed nuclei, granular, PHAGOCYTIC 
2. Lymphocyes (20 to 30%): spherical, one large nucleus, non-granular, SPECIFIC IMMUNITY (releases antibodies)  
3. PLATELETS: 
1. aka Thrombocytes 
2. Disk shaped, no nuclei, granular (granules in cytoplasm)
3. Aid in blood clotting

BIO 12 UNIT 4: Study Notes

PLASMA

Major Components:

1. Water (90-92%): maintains blood volume and transports molecules [source: absorbed from intestine]
2. Proteins (7-8%): maintains osmotic pressure and pH [source: liver]
1. Albumin (maintains blood volume and pressure)
2. Globulins (transport cholesterol); fight infection)
3. Fibrinogen (clotting)
3. Salts (>1%): metabolism; maintains osmotic blood pressure and pH [source: absorbed from intestine]
4. Gases (O2 and CO2): cellular respiration, end products of metabolism [source: lungs and tissues]
5. Nutrients (lipids, glucose, amino acids): provides food/energy for cells [source: absorbed from intestine]
6. Wastes (Urea): excretion by kidneys [source: liver]
7. Hormones, Vitamins, etc.: Aid in metabolism [source: varied]

BIO 12 UNIT 4: Study Notes

PATHWAY OF BLOOD

Aorta-->Arteries-->Arterioles-->Capillaries at major body organs and regions-->Venules-->Veins-->Inferior/Superior Vena Cava-->RA-->(via tricuspid AV valve) RV-->(via Pulmonary semi-lunar valve) Pulmonary Trunk-->Pulmonary Arteries-->Pulmonary Arterioles-->Pulmonary Capillaries (lungs)-->Pulmonary Venules-->Pulmonary Veins-->LA-->(via bicuspid/mitral AV valve) LV-->(via Aortic semi-lunar valve) Aorta

Video... Excellent and informative explanation of blood flow in heart:

http://www.youtube.com/watch?v=mH0QTWzU-xI

BIO 12 UNIT 4: Study Notes

FETAL VS ADULT CIRCULATION 

FETAL: Receives O2ated blood from the placenta and bypasses pulmonary circulation, 4 structures that adult does not have:

1. Oval Opening (Foramen Ovale): Between L and RA (flap acts as a valve), blood from the RA is shunted into the LA (does not need to go through the process of moving to the RV)
2. Arterial Duct or Ductus Arteriosus: Connection between pulmonary artery and aorta, reroutes blood away from lungs and sends it directly to the aorta
3. Umbilical Arteries and Veins: Arteries send deO2ated blood and wastes away from the heart and towards the placenta, Veins send O2ated blood and nutrients from the placenta to the fetus (heart)
4. Venous Duct or Ductus Venosus: Connection between umbilical vein and vena cava (liver), mixture of O2ated blood (umbilical vein) and deO2ated blood   (Vena Cava)

PATHWAY OF BLOOD: UMBILICAL VEIN-->VENOUS DUCT-->INFERIOR VENA CAVA-->RA-->OVAL OPENING-->LA-->LV-->AORTA


or UMBILICAL VEIN-->VENOUS DUCT-->INFERIOR VENA CAVA-->RA-->RV-->PULMONARY TRUNK/ARTERY-->ARTERIAL DUCT-->AORTA-->BODY (UMBILICAL ARTERIES-->PLACENTA)




A Great Video explaining Fetal Circulation:
http://www.youtube.com/watch?v=uwswhoKfkmM

ADULT: Has none of the fetal structures mentioned above AND has both Pulmonary and Systemic Circulation (uses lungs)

BIO 12 UNIT 4: Study Notes

PULMONARY VS SYSTEMIC CIRCULATION

PULMONARY-- Circulates blood from the heart to the lungs and from the lungs to the heart

**Right side of heart: RA-->RV-->PULMONARY TRUNK-->PULMONARY ARTERIES-->PULMONARY ARTERIOLES-->LUNGS (GAS EXCHANGE, BLOOD BECOMES O2ATED, CAPILLARIES)-->PULMONARY VENULES-->PULMONARY VEINS--> HEART (LA)

• ARTERIES (PULMONARY)- DeO2ated blood (away from heart)
• VEINS (PULMONARY)- O2ated blood (towards heart)

SYSTEMIC-- Circulates blood from the heart to the body (tissues and organs)

**Left side of heart: LA-->LV-->AORTA-->BRANCHES OF AORTA (ONE OF THE MANY PATHS)-->ORGANS AND BODY REGIONS 

• VEINS- DeO2ated blood (towards heart)
• ARTERIES- O2ated blood (away from heart)

BIO 12 UNIT 4: Study Notes

BLOOD VESSELS

1. ARTERIES: Thick walls, inside layer (endothelium), move blood away from heart and towards arterioles (O2ated) 

1. Inner Layer: Epithelial cells
2. Middle Layer: Elastic tissue and smooth muscle
3. Outer Layer: Fibrous connective tissue **Walls help with function to expand after heartbeat/maintain blood pressure**
2. ARTERIOLES: Smaller arteries, middle layer=smooth muscle, fibers of muscle contract and relax relating to blood pressure, transports O2ated blood towards capillaries (away from heart)
3. CAPILLARIES: Narrow, one-cell thick, endothelium walls, form capillary beds, regulates blood flow from the arterioles to the venules (bridge), gas exchange/nutrient exchange site--> O2 and other nutrients leaves thin capillary walls and joins tissue fluid, wastes diffuse into capillary                                     
4. VENULES: Small veins that drain capillary bed and join to form a vein, moves blood towards heart (deO2ated towards veins)   
5. VEINS: Has valves, brings deO2ated blood from capillary (venules) to the heart, valves allow for blood to flow in the right direction in the heart and prevent backflow, blood reservoirs (contain much of blood volume) 

                          

BIO 12 UNIT 4: Study Notes

SYSTOLE AND DIASTOLE PRESSURES

• SYSTOLE: Highest arterial pressure while heart is pumping (ventricles are contracting)
• 110-150 (normal for adult)--> fluctuates and differs depending on individual and activity/stress
• DIASTOLE: Lowest arterial pressure when heart is at rest (ventricles are relaxing)
• Should be 90 < (remains constant) 

The norm is 115/75 (Systolic/Diastolic)

VIDEOTIME... THE CARDIAC CYCLE: 

http://www.youtube.com/watch?v=jLTdgrhpDCg

BIO 12 UNIT 4: Study Notes

FACTORS AFFECTING BP: HYPERTENSION AND HYPOTENSION

• HYPERTENSION: High blood pressure (mild systole > 140 BUT severe systole > 180)
• Causes: Diet (fatty foods), obesity, hormone malfunction, arteries hardening, smoking, proper functioning kidneys help regulate this increase, reduction of stress, avoiding smoking, and eating healthy are factors that help regulate/counteract hypertension
• HYPOTENSION: Very low blood pressure (systole < 100)
• Causes: Weak pumping of heart (Often genetic or hereditary), kidneys regulate BP [ensure it does not get too low], ADH (increases BP), Renin (increases BP), and Aldosterone (increases BP)--> Response/regulation factors of Hypotension (counteract effects)

BIO 12 UNIT 4: Study Notes

AUTONOMIC NERVOUS SYSTEM REGULATION

• Involuntary Control of blood pressure and heart rate
• BP too low ---> Response is CONSTRICTION of arterial walls (smooth muscle)
• BP too high ---> Response is RELAXATION of arterial walls (smooth muscle)
• 2 Subdivisions of Nervous System:
• Sympathetic: Increases BP by increasing heart rate (Contraction: works when BP is too low, excitation, "fight or flight", unusual/dangerous situations)
• Parasympathetic: Decreases BP (Inhibits Sympathetic system, prevents an increase in BP, decreases heart rate, relaxes, works when BP is too high, stabilizer)

HERE IS A HELPFUL VIDEO EXPLAINING THE CONCEPT:

http://www.youtube.com/watch?v=YFYRosjcVuU

BIO 12 UNIT 4: Study Notes

SA Node, AV Node, Purkinje Fibers

• SA NODE= Found at upper portion of Right Atrium (wall), initiates the heart beat, sends out an "excitation" impulse every 0.85 sec to cause atrial contractions, keeps heartbeat regular (pacemaker)
• AV NODE= Found in base of Right Atrium (near septum), signals ventricular contraction by sending signals to the pukinje fibers
• PURKINJE FIBERS= Small and numerous, extending from two large fibers that carry the signal from the AV node through the ventricular walls, responsible for ventricular contractions occuring

VIDEO TIME... :)

http://www.youtube.com/watch?v=IR0nWe47eek

BIO 12 Fetal Pig Dissection Assignment

Observations: looks small, yellow, undeveloped, excess skin, feels moist, soft, toes are hard, smells like fermalphadide (stinky)
Female Pig indicated by flap located near the tail of the pig

DISCUSSION: It was a unique experience which I thoroughly enjoyed, it connected all of the big ideas of the course so far and was rich in learning opportunities. I was surprised by how small the pig was, how large the liver was, how delicate the pig was, how weird the stomach was, and how peculiar the brain was. What interested me was uncovering the various vital organs of the pig anatomy (ie locating the lungs, heart, gall bladder, etc.) This was a valuable learning experience because it for the first time visualized , the various body systems we have learned about this year in a central anatomy that we were face to face with (more meaningful than a textbook diagram). The pig showed the interconnectedness of the body systems (the digestive and excretory system, rectum, intestine, anus, the respiratory system and circulatory system, the heart, lungs, etc.)