Biology 10 - General Biology Lecture 14 Circulatory System Blood ...

Biology 10 - General Biology
Lecture 14
Circulatory System
http://www.youtube.com/watch?v=D3ZDJgFDdk0&feature=related
Blood: Fluid residing w/in :
• Composition: Plasma & Blood cells
1. Plasma:
Contains:
2. Cells:
O 2 & CO 2 , Nutrients & Minerals
Contains:
a. Erythrocytes:
b. Leukocytes:
c. Thrombocytes:
A. Erythrocytes
Function: Carry:
Quantity: ~5 million/mm 3 blood
Site of Production:
Hemoglobin:
Holds :
HEME: Contains :
Iron + Oxygen =
Blood with a lot of Oxygen is :
98% Saturated w/ :
Blood w/ less Oxygen is :
70% saturated w/ :
http://www.youtube.com/watch?v=WXOBJEXxNEo&NR=1
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. White Blood Cells: Leukocytes
Function:
5 different WBCs
(Body’s internal Defense)
Each has a specific function
Recognizing foreign substance
Initiate FIGHT
Eating foreign substances
Increasing blood flow to infection
Remembering an infection
http://www.youtube.com/watch?v=JnlULOjUhSQ&feature=related
c. Platelets: Thrombocytes
Function:
Stops bleeding
Transport Tubes: Blood Vessels
Three Different types:
1. Arteries: Carry blood :
• Transport blood :
• PULSE:
Pressure PUSHES blood to :
Correlated with each heart beat
Cause: Blood pushing :
Palpable
• Usually transports :
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Exception: PULMONARY ARTERY
2. Veins: Carry blood :
• Transport blood :
NO :
Carries Deoxygenated blood to :
• Usually transports :
Exception: PULMONARY VEIN
Leaves Lungs carrying Oxygenated blood
• Problem: Transport LOW pressure blood
“How does blood get back to the heart?”
Average pressure:
Blood flow:
a. Veins ABOVE the heart:
Blood falls back to heart
b. Veins BELOW the heart:
Veins below heart: Blood is pushed by:
Venous Valves: Prevent :
Blood can NOT fall back to heart
Significance: Varicose Veins: Venous Valve incompetence
3. Capillaries: Connect Arteries to veins
• “Business end”; Cells

Blood Pressure: Pressure exerted by blood on :
Heart: Cardiac contractions create Pressure
Systole : Cardiac
Diastole: Cardiac
Highest pressure in vessel
Heart
Systolic Pressure
Lowest pressure in vessel,
Heart
Diastolic Pressure
http://www.youtube.com/watch?v=luppKLO74vg&feature=related
Clinically:
• High Blood Pressure: Hypertension
Cause: Atherosclerosis
Systolic: Greater than
Diastolic: Greater than
Narrowing of Arteries: Due to
http://www.youtube.com/watch?v=fUcLrdPJurU&feature=related
• Risks:
• Prevention:
1. Heart Attacks
2. Strokes
3. Blood vessel damage
4. Kidney failure
Reduce cholesterol, saturated & trans fats
Exercise at least :
Study Questions:
1. What is the function of the blood? What are the two main components of blood? Where are the blood cells formed?
2. What is the plasma composed of?
3. What are the most numerous blood cells? What is their function? What is the overall function of the Leukocytes
(WBCs)? What are some of the individual functions of WBC?
4. What is the primary function of thrombocytes (platelets)?
5. What is the function of hemoglobin? What is the difference between oxygenated and deoxygenated blood? What
mineral binds oxygen?
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6. Where does blood change from being oxygenated into being deoxygenated?
7. What is thee most important difference when identifying an artery from a vein (hint: think of the flow of blood) What
are the difference between arteries and veins with respect to pressure – which ones pulse?
8. Do arteries ALWAYS carry oxygenated blood? Explain. Which large artery does NOT carry oxygenated blood?
9. If you cut yourself & bright red blood was squirting out of the vessel; what vessels did you cut ; artery or vein?
10. Which vessels allow for the exchange of materials (nutrients and gases) between the blood and the tissue?
11. What is the blood pressure? What is the difference between systolic and diastolic pressure? When you feel your pulse,
what are you actually feeling? What causes the blood to pulse?
12. Why is the arterial blood pressurized? Are veins pressurized? Explain what the problem is for these low pressure
vessels. How do the vessels solve this problem? - how does blood get back to the heart from the legs?
13. What is hypertension? What are some of the problems associated with hypertension? What are some things you can
do to reduce your risk of hypertension? What is the blood pressure measurement for someone that is just beginning to be
hypertensive?
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