Objective: You will be able to name and give the function of the blood components.

Do Now:• Read all of p. 943

• Compare the circulatory system with a city

Transport

• Transport involves absorbing substances in the blood and circulating it through the body

• Materials that the blood carries includes dissolved and suspended materials

Blood Vessels

• Arteries transport blood away from the heart– They have thick, muscular walls

• Veins transport blood to the heart– They have thin walls– Contain valves to prevent the backflow of

blood

• Capillaries have walls that are only one cell thick– The exchange material with the blood and the

intercellular fluid (ICF)

Figure 42.8 The structure of blood vessels

Intercellular Fluid (ICF)

• ICF surrounds all of the cells of the body and exchanges materials with the blood and the cells– It is mostly made up of water

• The ICF is picked up by lymph vessels and is now called lymph– Lymph vessels are one cell thick and contain

valves

Tissue cell INTERSTITIAL FLUID

CapillaryNet fluidmovement out

Net fluidmovement in

Direction of blood flow

Capillary Redbloodcell

15 m

Blood

• Blood consists of the liquid plasma and a variety of cells

• Plasma is the liquid part of the blood– Mostly consists of water

– Carries everything including wastes, CO2, antibodies, etc…

• Does NOT carry O2

Red Blood Cells (RBC)• Carry oxygen

– Hemoglobin on the RBC’s carry the O2

– An RBC does not have a nucleus– It is anaerobic

Platelets• Platelets are involved with clotting

– Platelets near an injury rupture and release a chemical

– This chemical causes an enzyme-controlled series of reactions to form a clot

Platelets

White Blood Cells (WBC)

• White blood cells have a nucleus

• They fight off bacteria and viruses– These “bad things” are called antigens

• There are two types of WBC’s– Phagocytic WBC’s engulf the antigens– Lymphocytes make antibodies that attack the

antigens

Phagocyte

Lymph

• The lymph vessels bring the lymph to lymph nodes

• Phagocytic WBC there, clean the lymph of bacteria and dead cells

• Once the lymph is cleaned, it is returned to the blood

RBC

WBC

Figure 42.5 The mammalian heart: a closer look

Right Atrium

Left Atrium

The Heart• It is a pump that sends blood throughout

the body• It is made of muscle we call cardiac

muscle• It is separated into left and right halves by

the septum• It has four chambers

– Two atria receive the blood coming back to the heart

– Two ventricles pump the blood out to the body

Figure 42.4 The mammalian cardiovascular system: an overview

Circulation types

• Pulmonary circulation is the flow of blood from the heart to the lungs and back to the heart

• Systemic circulation is the flow of blood from the heart to the rest of the body and back to the heart– Coronary circulation is a PART of systemic– Coronary supplies blood to the heart through

coronary arteries

Back to the Heart

• The two atria receive blood returning to the heart– They are thin walled

• The ventricles pump blood out of the heart– They have very thick walls

Figure 42.5 The mammalian heart: a closer look

Right Atrium

Left Atrium

Figure 42.4 The mammalian cardiovascular system: an overview

Heart Dissection

• Find the four chambers of the heart• Identify the flowing structures

– Valves– Vena cava– Pulmonary artery– Pulmonary vein– Aorta

• You find these structures by using your fingers

Blood pressure• Refers to the pressure on the arteries

when the ventricles contract.• The contraction period is called systole

– Greatest pressure on the arteries

• The non-contraction period is called diastole– Lowest pressure on the arteries

• A blood pressure of 120/70 means:– Systolic number is 120– Diastolic number is 70

Figure 42.12 Measurement of blood pressure (layer 1)

Artery

Figure 42.12 Measurement of blood pressure (layer 2)

Artery

Rubber cuffinflatedwith air

Arteryclosed

120

Pressurein cuff above120

Figure 42.12 Measurement of blood pressure (layer 3)

Artery

Rubber cuffinflatedwith air

Arteryclosed

120 120

Pressurein cuff above120

Pressurein cuff below 120

Sounds audible instethoscope

Figure 42.12 Measurement of blood pressure (layer 4)

Artery

Rubber cuffinflatedwith air

Arteryclosed

120 120

70

Pressurein cuff above120

Pressurein cuff below 120

Pressurein cuff below 70

Sounds audible instethoscope

Sounds stop

Blood pressureReading: 120/170

Circulatory Malfunctions

• Cardiovascular diseases are malfunctions that affect the heart and blood vessels– High blood pressure is characterized by

having high pressure on the arteries. It damages the arteries and weakens the heart

– Heart attacks include• Angina pectoris which is a partial blockage of a

coronary artery• Coronary thrombosis which is a complete

blockage of a coronary artery

Malfunctions continued

• Blood conditions– Anemia is the inability of the blood to

transport enough oxygen• May be caused by low amount of hemoglobin or

low amount of RBC’s

– Leukemia is a cancer that affects the bone marrow.

• Blood is produced in the bone marrow. So this cancer is the uncontrolled production of nonfunctional WBC’s