1. Mammalian Transport System
Ch. 8 Part 1

2. Cardiovascular System
Transport system of the body
Carries nutrients (Glucose!) and oxygen TO the cells of the body
Carries waste products and carbon dioxide (CO2) AWAY from the cells
Transports chemical messages between cells (HORMONES)
Fights Disease (White blood cells)
Contains a variety of proteins

3. Members of the Cardiovascular System
Heart (pump)
Blood Vessels
Arteries
arterioles
Veins
venuoles
Capillaries
Blood
Members of the Cardiovascular System

4. Closed, double circulation
Closed= b/c blood travels inside vessels
Double circulation
Systematic circulation
Vessels taking blood from left ventricle in heart to cells in tissue throughout the body and back to right atrium
Pulmonary circulation
Blood taken from right ventricle to lungs and back to left atrium

5. Click here to see it in action!
The Heart
Muscular (cardiac muscle) organ in chest
2 pumps (Right and left side)
Work together to move blood all around your body
Each side has a top (Atrium) and a bottom (ventricle)
4 chambers of heart
Heart muscles contract push blood from the heart to the blood vessels

6. Overview of Heart (more next week)
Right Atrium RA
Right Ventricle RV
Left Atrium LA
Left Ventricle LV
Aorta
Superior/Inferior Vena Cava
Pulmonary Artery PA
Pulmonary Vein PV

7. Things to Know ATRIUM Blood is ALWAYS ENTERS atrium VENTRICALS
Blood ALWAYS LEAVES the ventricles
ARTERY
ALWAYS carries blood AWAY from heart
VEIN
ALWAYS carries blood TOWARDS the heart

13. Anatomy of a Blood vessel
Endothelium
Squamous epithelium
Single layer
Smooth, no friction
Rests on elastic fibers
Tunica Media
Middle layer
THICKEST
Contains:
Smooth muscle
Collagen
Elastic fibers (tunica intima)
Tunica Externa
Outermost layer
Elastic fibers

15. Blood Vessels Arteries Veins Capillaries Carry blood AWAY from heart
Carry blood back TO the heart
Capillaries
Teeny, tiny blood vessels that connect to arteries and veins
Nutrients and gas can pass through the capillaries from the blood to the cells that need them

16. Arteries Elasticity important Arteries close to heart
Many elastic fibers in tunica media
Arteries farthest from heart
Less elastic fibers in tunica media
More muscle fibers
Highest pressure is in arteries
Aorta (most pressure)
Diameter= 2.5 cm
Thickness of wall = 2 mm
Arteries have mechanisms to alleviate drastic changes in pressure
Ventricle contracts (HP in artery)
Arteries widen a HP
Helps decrease pressure
Ventricle relaxes (LP in artery)
Arteries recoil (narrow) at LP
Helps increase pressure slightly

17. Capillaries Tiny vessels
Just enough space for Red blood cells to squeeze through
Walls are one cell thick
Endothelial cells
Gaps in walls allow PLASMA to leak out into tissue spaces
Function:
deliver nutrients, hormones, and other body requirements to cells that make up tissues
remove waste products from those cells
Small size and thin walls minimize diffusion distance, enabling rapid exchange

18. Veins Carry low pressure blood back to the heart
Walls do NOT need to be tough or elastic
Lumen is larger than arteries, reduces friction that would slow down movement of blood
Have SEMILUNAR VALVES
One way valves that only allow blood into vein (not out)
Moves due to contractions in skeletal muscle, pushes blood up against gravity

21. Pressure Highest pressure in vessels when blood is leaving the heart
120 mmHg or 16kPa
1 mmHg = 0.13 kPa
Pressure changes in Circ. Sys.
Arteries highest blood pressure
Pressure oscillates with heart beat
Stretching & recoiling of artery walls helps smooth oscillations so pressure becomes gradually steadier the further the blood moves along the arteries (pressure slowly decreases)
Capillaries Total cross-sect. area greater than arteries that supply them
Blood pressure is less inside capillaries
Veins very low pressure
Long way from pumping effect of heart