Presentation on theme: "C IRCULATORY S YSTEM Life function: Transport- The process by which materials such as(nutrients,O 2,CO 2,waste, hormones and immune factors) are moved."— Presentation transcript:
C IRCULATORY S YSTEM Life function: Transport- The process by which materials such as(nutrients,O 2,CO 2,waste, hormones and immune factors) are moved between cells=circulatory system
T HINK P AIR S HARE We just finished digestion. What is the relationship between digestion and transport? Digested materials enter the bloodstream through the villi in the small intestine.
T RANSPORT AND C IRCULATION In order for material to enter cells and move between cells, a transport system is needed. This system is called the circulatory system.
H UMAN HAVE A CLOSED CIRCULATORY SYSTEM Includes 3 parts 1) A fluid (blood)to carry material. 2) A network (system) of tubes (blood vessels) to carry fluid. 3) A pump (heart) to push fluid along.
W HILE OTHER O RGANISM ’ S HAVE AN OPEN CIRCULATORY SYSTEM The fluid flows freely throughout the body and is not contained in tubes.
B LOOD V ESSELS 3 kinds of vessels=arteries, veins, capillaries. All together the vessels are thousands of kilometers long. Carry blood through heart, lungs and body.
A RTERIES Have thick muscular walls that expand and contract as blood is pumped. This accounts for your pulse.
A RTERIES Carry blood away from the heart to the organs of the body. Elasticity of the walls exert pressure on the blood inside =blood pressure. Can be blocked with fatty deposits. Large arteries branch, forming smaller vessels eventually dividing into arterioles (small arteries) and then capillaries.
Why are capillaries important parts of the circulatory system?
C APILLARIES Smallest vessels one cell thick. Near everybody cell. Exchange of materials between blood and cells. they connect the smallest arterioles with the smallest veins (venules)
Capillaries are where important materials are exchanged between the blood and your cells
BLOOD (in capillary) CELLS IN BODY Oxygen, nutrients, hormones 2 – hormones, metabolic wastes including Carbon dioxide
The capillaries “do business” with the cells
Capillaries readily exchange dissolved materials by diffusion between the blood and the ICF surrounding all body cells.
V EINS Carry blood from the body to the heart. Walls are thinner than those of the arteries.
V EINS Contain valves that allow blood to flow in only one direction. If your valves fail to work,blood builds up, veins loose elasticity, and varicose veins form.
S PIDER V EINS
L YMPHATIC SYSTEM Fluid from the bloodstream is constantly leaking from the capillaries into surrounding tissues.
L YMPHATIC SYSTEM This fluid helps bring nutrients to cells that need them, It also helps cells fight off infectious disease.
W HAT HAPPENS TO ALL THIS FLUID ? A network of vessels called the lymphatic system collected the fluid (lymph), and returns it to the circulatory system.
L YMPH NODES Lymph nodes exist at various places in the body. 1.These are glands filter foreign matter from the lymph. 2. and prevent disease causing organism from entering the bloodstream.