Laboratory #11 Circulatory system
By the end of this lab, you should understand the basics of the circulatory system including function of blood cells, blood pressure, heart anatomy, and strucure blood vessels.

KEY WORDS

Heart                                   Capillary

Blood                                   Plasma

White Blood Cell(WBC) or Leukocyte      Blood Pressure

Red Blood Cell(RBC) or Erythrocyte      Systolic Blood Pressure

Artery				        Diastolic Blood Pressure
 
Vein			          	Pulse

A. The Heart
The human heart is composed of a right and left atrium as well as a right and left ventricle. The heart is the organ responsible for pumping blood throughout the human body. The pathway of blood goes like this:

Right Atrium--Right Ventricle--Lungs--Left Atrium--Left Ventricle--Body (via Aorta and Branches)--Right Atrium(via Vena Cava)

Can you identify the regions of the heart labeled in the following pictures?

A = left ventricle
B = left atrium

A = right ventricle
B = left ventricle
C = right atrium

B. Blood
We will discuss three basic components of blood. The first is plasma, which is the straw-colored fluid that makes up roughly 55% of the blood. The plasma contains erythrocytes and leukocytes. Erythrocytes lack nuclei and carry oxygen to other cells of the body. Leukocytes contain nuclei and function in the immune response.

Most of the cells in the following picture are erythrocytes. What type of cell is being pointed to?

white blood cell C. Blood Vessels
There are three main types of blood vessels that are found in the human body- arteries, veins, and capillaries. Arteries carry blood away from the heart and have an extremely thick smooth muscle layer. Veins carry blood back to the heart and have less smooth muscle within their walls. Capillaries connect arteries and veins and are roughly one erythrocyte in diameter.

Can you identify the artery and vein in the picture below?

A = artery
B = vein

D. Pulse
Pulse can be defined as the number of contractions of the heart muscle per minute. Find the pulse on your wrist. Place left index and middle finger on your right wrist. You should now feel your pulse and count the number of beats per minute to determine your own pulse.

5. Would exercise increase or decrease you pulse rate?
increase
E. Blood Pressure
Blood pressure can be defined as the amount of pressure on the surface of the vessels caused by flowing blood. Systolic blood pressure is measured as blood is leaving the heart and is usually written as the top number. Diastolic blood pressure is measured as the heart relaxes and is the bottom number.

                      Systolic Blood Pressure(100-140 mm Hg)

                      Diastolic Blood Pressure(70-85 mm Hg)

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