3.2 The Circulatory System

Text book pages 68-70

Vocabulary:

• Arteries• Veins• Capillaries• Atria• Ventricle

Circulatory system

• Brings every cell oxygen

• No cell is more than 2 cells away from a blood vessel

WOW!!

– We have 60 trillion cells (60, 000, 000, 000, 000)

1, 000, 000

100, 000, 000

1, 000, 000, 000

1, 000, 000, 000, 000

WOW WOW

• We have 96 000 km of blood vessels (the earth is 40, 075.16 km around…. So that is MORE then twice around the earth!!

Circulation

• Blood in vessels carry:– O2 and nutrient fluids to the cells

– CO2 and waste away from cells

• 3 main types of vessels:– Arteries: carry blood away from heart– Veins: carry blood to the heart– Capillaries: smallest vessel (size of 1 RBC)

Our Heart

• 4 chambers– Two atria • Receive blood into heart• Top or heart

– Two ventricles• Pumps blood away from hearth• Bottom of heart• Stronger, more muscular

Flow of blood through the heart:

• Veins (deoxygenated blood from body)• Right atrium (RA)• Right ventricle (RV)• Lungs (get exchange CO2 gas for O2 gas at the

alveoli)• Left atrium (LA)(oxygenated blood form lungs• Left ventricle (LV)• Aorta• Body

Circulation song

• http://www.youtube.com/watch?v=LqhvmUEdOYY&p=9C8E1219DB4742B9&index=21

A one-way flow

• Valves = one way doors– Found between RA and RV, and LA and LV– Ventricles and arteries– In veins

Our heart beat

• “LUBB” “DUBB”• “LUBB” = ventricles contracting and closing

valves between Atria and Ventricles• “DUBB” valves closing between the arteries

and the ventricles

Heart Beat animation: http://www.youtube.com/watch?v=AOiyjNFB0as

Heart video

• http://www.youtube.com/watch?v=S3vY5oyXmeI

Circulation song

• http://www.youtube.com/watch?v=LqhvmUEdOYY&p=9C8E1219DB4742B9&index=21