Ch 38 Circulatory System

AP Lecture

4 chamber heart is double pump = separates oxygen-rich & oxygen-poor blood; maintains high pressure

What’s the adaptive value of a 4 chamber heart?

2 3 4

low pressureto body

low O2

to body

high pressure & high O2

to body

Background Function: transport gases,

hormones, blood, nutrients, ect.

Parts Heart- muscular pump Blood – fluid Blood vessels – conduits of fluid

Open Circulatory System Fluid leaves the vessels and bathes the tissues then returns back to the heart Ex: arthropods and mollusks

Closed Circulatory System

Blood vessels keep fluids contained Ex: annelids and vertebrates

Mammal Heart Arteries- carry blood away from

the heart Stronger; endure more pressure

Veins – carry blood back to heart Assisted by gravity and skeletal

muscle Capillaries- thin walled;

exchange between blood and interstitial fluid

Blood vesselsarteries

arterioles

capillaries

venules

veins

artery

arteriolesvenules

veins

4 chambered heart Pulmonary – lungs Systemic – body

Movement in mammal heart

1. Blood from the body enters the right atrium via vena cavae (oxygen poor)

2. Blood enters the right ventricle through the atrioventicular (AV) valve (oxygen poor)

3. Right ventricle pumps blood through pulmonary artery to the lung (poor oxygen)

4. Bloods moves from lung to left atrium via pulmonary vein (oxygen rich)

5. Blood moves into the left ventricle via the AV valve (oxygen rich)

6. Left ventricle pumps blood to body through aorta (oxygen rich)

Mammaliancirculation

What do blue vs. red areas represent?What do blue vs. red areas represent?

pulmonary

systemic

systemic

http://bio-animations.blogspot.com/2008/04/human-heart-how-it-pumps.html

Cardiac Cycle Systole – ventricle contracts

Which means the AV valves close “lub”

Diastole – ventricle relaxes

Which means the aortic and pulmonary valves close “dub”

Measurement of blood pressure

High Blood Pressure (hypertension) if top number (systolic pumping) > 120 if bottom number (diastolic filling) > 80

AV

SL

AV

Blood Cells suspended in plasma

RBC (erythrocytes) WBC (leukocytes) Platelets- blood clotting

Lymphatic System Collects excess fluid and returns it to the blood Lymph nodes- produce and house lymphocytes that fight pathogens in the lymph fluid

Lymph system

Production & transport of WBCs

Traps foreign invaders

lymph node

lymph vessels(intertwined amongst blood vessels)