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Vertebrate Transport System

Chapter 9:

1)    Differentiate between transport and circulation.

2)    List and describe the three  components of circulatory system.

3)    Explain how blood flows in a closed circulatory system.

4)    Describe the structure of an artery, a vein, and a capillary.

5)    Describe the structure of a mammalian heart.  Compare this to fish and amphibian hearts.

6)    Explain the diastole and systole periods of the heart cycle.

7)    Describe the heart sounds and how they originate.

8)    Explain how the heartbeat is initiated and controlled in humans.

9)    Compare diastolic and systolic blood pressure and how they affect the flow of blood.

10)    Explain pulmonary, systemic, coronary, hepatic-portal and renal circulations.

11)    What is interstitial (intercellular fluid) and how is it formed?

12)    Briefly describe the structure and function of the lymphatic system.

Chapter 10

13)    List the function of blood.

14)    Briefly describe the origin, structure and function of the following components of blood: plasma, red blood cells, white blood cells (leucocytes and lymphocytes) and platelets.

15)    Outline the process of blood clotting.

Answers

1) Circulation is the movement of materials within a cell or between parts of an organism.
        Transportaion refers to circulation and all other processes by which substances pass into or out of cells and move within the organism.  (page 144)

2) The circulatoy system has three main components:
        1) A fluid in which transported materials are dissolved, ie blood
        2) A network of tubes or body spaces through which the fluid flows, ie arteries, veins, blood cells
        3) A means of driving the fluid through the tubes or spaces, ie heart
(page 144-145)

3) 

4) Ateries are the blood vessels that carry blood away from the heart.  Their walls are thick and elastic so they can snap the blood along.  The snapping together of an artery is the pulse you feel when checking your heart rate.  The blood moves because of the high pressure system created here.  They contain layers of connective tisue, muscle tissue, and epithelial tissue.
        Veins are the blood vessels that return blood from the body tissues to the heart.  Their walls are thin and only slightly elastic.  Veins have a large volume capacity for blood.  They opperate on a lower pressure than the arteries.  There are valves that allow for blood to flow only in one direction so blood can't pool causing the vein to stretch.
        Capillaries connect Arterioles (smallest of the arteries) and venules (smallest of the veins).  The walls of the capillaries is just a single layer of epithelial cells.  Capillaries are so small that red blood cells pass through them in single file. (page 148-149)

5) The outside of the heart is surrounded by a tough protective membrane, the pericardium.  Inside, the heart is divided into four chambers.  (SEE FIG 9-7 p. 150)  The two upper chambers are thin-walled and are called the atriaThe two lower, thick-walled chambers are the ventricles.  Dividing the two sides is a partition called the septum.  There are valves on each entrance to each chamber. (page 149)

6) Diastole and systole are the two main periods of the pumping action of the heart.  Diastole is the period of relaxation.  During this time the atrioventricular valves are open (See Fig 9-8 p.150) and blood flows form the atria into the ventricles.  Systole is the period of contration.  During this time the ventricles contract, opens the semilunar valves and travels to the lungs.  Blood comes back to the other side of the heart and the process occurrs again, but this time blood is pumped to the body. (page 150)

7) The heart beat is a "lub-dup" sound.  The "lub" sound is produced by the closing of the tricuspid and bicuspid valves.  The "dup" sound is made by the closing of the semilunar valves.

8) The heart contracts by an electrical impulse sent by the sinoatrial node, otherwise known as the pacemaker.  The sinoatrial node is located in the right atrium.  The heart rate is sped up by nerve impulses from the cardioaccelerator nerves, and slowed down by impulses coming from vagus nerves.

9) Blood pressure is a measure of the height of a column of mercury in a tube.  During systole the mercury rises to about 120 millimetres, during diastole the mercury drops to about 80 millimetres.  If someone has high blood pressure, they most likely have cholesterol lining the inside of their arteries.  This causes heart attacks.

10) Pulmonary Circulation is the circulation of blood from the heart to the lungs and back to the heart.  In this process blood is reoxygenated.
        Systemic Circulation is the circulation of blood from the heart to the rest of the body and back to the heart.  The blood carries oxygen for the cells in the body to use.
        Coronary Circulation is the circulation of blood throughout the heart.  The heart is living too.  It needs oxygen.  Blood is carried by the coronary arteries.
        Hepatic-portal Circulation is the flow of blood from the digestive tract to the liver.  In the digestive tract nutrients are reabsorbed into the blood stream.  They travel in the blood stream to the liver where they can easily diffuse into storage cells in the liver.
        Renal Circulation is the circulation of blood to and from the kidneys.  The body must dispose of wastes by excretion.  All wastes are sent in the blood stream to a place where it can be excreted.
(page 155-156)

11) Interstitial fluid (intercellular fluid) serves as a medium between the capillaries and body cells.  Any substance exchanged between blood and body cells must diffuse through the intercellular fluid.