Grade 8.Unit L.2 Circulation

(Do you know who this man is?? Ask your teacher about him? His name is Ibn Nafis, born 1213 He was born in Damascus, Syria, and worked in Cairo, Egypt)

The Standards

8.8.1 Know the basic structure of the heart and relate this to its function.

.

8.8.2 Know the different valves of the heart and how they function.

.

8.8.3 Know the positions, functions and names of the major blood vessels.

.

8.8.4 Recognize the differences between arteries, veins and capillaries, and relate their structure to their function.

.

8.8.5 Explain blood pressure and why high blood pressure is an indicator of circulatory problems .

.

Information on Ibn Nafis, TEACHERS USE http://www.muslimheritage.com/topics/default.cfm?articleID=209

Ibn al-Nafis is now most famous for being the first physician to describe the pulmonary circulation, or pulmonary transit of blood. His discovery disproved the thousand year-old theory of Galen who suggested invisible pores in the intraventricular septum. Ibn Nafis clearly stated that the "blood in the right ventricle of the heart must reach the left ventricule by way of the lungs alone and not through a passage connecting the ventricle, In addition, he is credited with early insight into capillary and coronary circulations,[2] which in addition to the pulmonary circulation form the basis of the circulatory system, for which he is called the father of circulatory physiology,[3] and "the greatest physiologist of the Middle Ages."[4] His work would not be surpassed until the 17th century, when the theory of the entire circulatory system, i.e. the continuous circular motion of the blood throughout the whole body, was proposed by William Harvey

Objectives:

1-Know the basic structure of the heart and relate this to its function.

2-Know the different valves of the heart and how they function.

3-Know the position, the function and the names of the major blood vessels.

4-Recognize the differences between arteries, veins and capillaries, and relate their structure to their function.

5-Explain blood Pressure and why high blood Pressure is an indicator of circulatory problems.

Key words

Atrium

Ventricles

Capillary

Vein

Artery

Pulmonary Artery

Pulmonary Vein

Aorta

Vena Cava

Fist

Chest

Chamber

Oxygenated

Atrium

Ventricle

Deoxygenated

(Explore ActivityHow Big Is Your Heart? The bigger you are, the bigger your heart is. Your heart is about the size of your fist. Your heart and fist will grow at about the same rate. . . .1. Make a fist. Use string and a ruler to find .its length: ___ its width: ___the distance around your fist: __2. On the basis of the measurements you made, what is the size of your heart is (roughly)? __ . )

The circulatory system works with other body Systems

.

Your circulatory system is made up of your heart, blood vessels, and blood. Blood vessels are tubes that carry blood through the body. The blood vessels form a closed circulatory system. In a closed circulatory system, blood never leaves the blood vessels.

. . .

1-Heart

The heart is a muscular organ that pumps blood throughout the body.

You can think of the heart as a double pump. The right side of your heart pumps blood to your lungs. The left side of your heart pumps blood to all other parts of your body

You can see the structure of the heart in the Figure 1.

. . . . .

(Figure 1)

Notice that the heart is divided into two sides by a thick wall called the septum. The heart also is divided into four parts or chambers. There are upper and lower chambers. Each upper chamber of the heart is called an atrium (the plural of atrium is atria). The lower chambers are called ventricles.

. . . ( ). .

The atria are like receiving rooms. They receive blood returning to the heart. The ventricles are like shipping rooms, they pump blood out of the heart to the rest part of the body.

How does blood flow through the heart? Blood flows from the atria to the ventricles. When the atria fill with blood, they contract and the blood is pushed into the ventricles. The ventricles contract and pump blood to other parts of the body.

. . . . . .

(Heart is a muscular organ which pumps blood around the body .)

(Ventricles: the lower chambers of the heart: )

(Atria: the upper chambers of the heart : )

Valves

(FIGURE 2)A valve is a. strong flap of tissue that acts like a one-way door. The valves keep the blood moving in only one direction. Blood can flow only from the atria to the ventricles. Blood cannot flow backward. Between the atria and ventricles there are valve. If the blood tries to go backwards, the valve shuts. There are also valves between the ventricles and the blood vessels. As the blood leaves the ventricles, it goes through the valves

. . . . . . .

(Valve: is a strong flap of tissue which acts as one-way door. : .)

Heartbeat

Your heartbeat is the rhythm of our heart pumping blood. If you could listen to your heartbeat through a stethoscope (is an instrument a doctor use to listen to heart beats) you would hear a lub-dub sound. The lub-dub sound is made by your valves opening and closing When the valves between the atria and ventricles snap shut, they make the "lub" sound. When the valve between the ventricles and blood vessels snap shut, they make a "dub" sound

. ( ) - . - . "" . "".

Q1: What role does blood play in our bodies?

?

_______________________________________________________

Q2: What materials are transported around our bodies?

______________________________________________________________________________________________________________

Q3: How does blood flow through the heart?

_____________________________________________________________________________________________________________________________________________________________________

Q4: What is the function of the heart?

_______________________________________________

Study the following picture, and then answer the following questions:

:

Describe the structure of heart according to the following:

1. The heart is made up of double pump. Explain the role of these pumps.

.

_________________________________________________________________________________________________________________________________________________________

2. The chambers of heart:

..

3. The system responsible for transportation in the body is __________________________

4. What is the role of septum

_____________________________________________________________________________________________________

5. Why are the valves important to the heart?

_______________________________________________

Complete the sentence: :

The system responsible for transportation in the body is ______________________________________

The human circulatory system made up of___________________and ___________________.

Each side of the heart is made of 2 chambers___________and______________.

(Mini-labMeasuring pulse rate: Materials.Clock or watch Procedure:1-Count your pulse for one minute, and then calculate how many times your heart beats in one hour, one day and one year.2- Jog in your place for two minutes. Then take your pulse for 1 minute. :1 .2 -- . 1 .)

Minor Blood vessels:

There are 3 types of minor blood vessels in the body

3

1-Artery:

The blood goes away from the heart through the arteries. The pressure of blood is high in arteries so to reach all the body. The artery walls are thick and elastic. Thats how you feel the pulse.

(Figure3)1 - : . . . .

2-Capillaries:

Capillaries are very narrow (one cell thick) blood vessels that reach the body cells where exchange of oxygen and nutrients take place in cells and carbon dioxide and other wastes are removed from cells. Capillaries move out to the veins.

FIGURE 4

2 - : ( ). . .

3-Vein:

Carbon dioxide and other wastes go to the heart through the veins. Veins have thinner walls. The pressure inside veins is much lower. The flow of blood in veins is helped by valves. (Valves prevent back flow of blood) The contraction of skeletal muscles helps move the blood back to the heart

3 - : . . . . ( ) .

Figure 5

(FIGURE 5)

Figure 6

( Figure7)

(Arteries: It carries blood away from the heart : )

(Veins: carries blood toward the heart : )

(Capillaries: ar