1. Human Biology Circulatory/Respiratory/ Excretory System
Ch. 37

2. Circulatory System Function
1. Delivers food & oxygen to cells.
2. Carries CO2 & wastes away from cells.

3. Blood _______ (_______________) – carry oxygen w/ hemoglobin
________(_______________) – fight diseases.
________ – liquid portion of blood containing nutrients
________ – clots blood

4. Blood Vessels
1. ________ – thick, elastic; carries __________________ blood away from the heart
2. ________ – thin, not elastic; carries _________________ blood back to the heart
3. _________ – smallest & thinnest blood vessels; connect arteries to veins; where _______________ occurs

5. Muscle Pumps (for veins)
_______ in veins prevent the backflow of the blood.
When muscles contract, they squeeze the veins allowing the blood to move up to the heart.

6. Heart Made of ________ muscles Has ___ chambers.
Right/left _______ = collecting chambers
Right/left __________ = pumping chambers
________ between atrium and ventricle prevent the backflow of blood

7. Pathway of blood flow Superior/inferior ____________ (biggest vein)
 ___________
 _____________
 ___________ artery
 to the lungs (pick up O2)
 ___________ vein
 _________ (biggest artery)
 to the rest of the body

8. Heartbeat Average heartbeat of an adult at rest = _____ beats/min
- Sounds of a heartbeat “lubb” “dubb” come from the _______ opening and closing in the heart.

9. Blood Pressure
Measure of the pressure that the blood exerts on the blood vessels
Systolic/Diastolic
= ave. adult ____ mm Hg/____ mm Hg
_________ pressure = ventricles contract; high
_________ pressure = ventricles relax; low

10. How is the heart beat regulated?
___________ – generates electrical signals to regulate heartbeat
________ _________ – part of the nervous system in the brain that controls the pacemakers.

11. Respiratory System Function 1. Obtain oxygen for metabolism.
(cellular respiration)
2. Eliminate _______ ____ and water.

12. Respiratory System Structures
Nasal Cavity (nose) -cilia trap dusts and purify the air
___________(throat) -helps air to pass through and traps microorganisms
___________ (voice box) -Makes the vocal cord vibrate and produce sounds.
__________ - Prevents food from going into respiratory tract
__________ (windpipe) - Main trunk of the respiratory system.
Located in the center of the chest cavity
_________/__________ (left & right) -Two branches at the bottom of trachea; branches into smaller bronchioles.
__________ – air sacs at the end of bronchioles; gas exchange occurs.

14. Mechanism of Breathing
Breathing results from the movement of rib muscles and ___________.
___________ = a layer of muscle tissue that helps in breathing by contracting or relaxing
Inhalation – rib muscles ________ & diaphragm ________; increases volume of chest cavity; air rushes in
Exhalation – rib muscles _______ & diaphragm ________; decreases volume of chest cavity; air rushes out.

15. Effect of Smoking
When someone smokes, their cilia are paralyzed, allowing particles to irritate the lungs.

16. Excretory System
Kidney -> _______ -> ________ -> ________

17. Nephron
A basic unit of ________