Ib Blood, Vessels, And Cardiovascular Disease

Front 1

What is transported by the blood?

Back 1

nutrients, carbon dioxide, oxygen, hormones, antibodies, urea, heat

Front 2

What is the blood composed of?

Back 2

plasma, erythrocytes, leucocytes (phagocytes and lymphocytes) and platlets

Front 3

Describe the relationship between structure and function in capillaries.

Back 3

1. Between arterioles and venules. Blood here is under low pressure (because the total volume of blood has been split into many, many capillaries) . The capillaries’ job is to exchange substances with interstitial fluid surrounding all of the body’s cells 2. Wall made of endothelium: A. Endothelium is smooth to reduce resistance to blood flow B. Only a single layer of cells so that the diffusion distance in or out is very small C. Pores (small openings) between some of the cells allow some of the plasma to leak out to form tissue fluid (interstitial fluid). Phagocytes can also squeeze through to look for bacteria, etc. of cells that have been infected by a virus. D. The opening (lumen) is very narrow, making the diameter of the capillary very small so it can fit in tiny spaces. E. By having many, many smaller capillaries rather than a few larger ones, there is a larger surface area of capillaries in the body…this makes exchange of oxygen, nutrients, etc. more efficient E. No valves

Front 4

Describe the relationship between structure and function in arteries.

Back 4

1. Move blood away from heart. Blood here is under a 3x higher pressure than in the vein (due to the high pressure caused by pumping by the heart) 2. Wall made of endothelium, muscle and connective tissue A. Endothelium (inner layer) is smooth to reduce resistance to blood flow B. The muscle + connective tissue wall is thicker than in veins, which makes it strong....important since the blood going through arteries is under higher pressure C. Thick muscular wall (which can be controlled by the nervous system and hormones) can control blood flow to different parts of your body…for instance towards/away from your skin depending on the outside temperature. It also helps move the blood on after a heart beat D. Thick layer of connective tissue (with elastic fibers) allows the artery to stretch and recoil. The ability to recoil between contractions helps maintain blood pressure and avoid damage to blood vessels E. Narrow diameter to help maintain blood pressure 3. No valves (unlike veins)

Front 5

Describe the relationship between structure and function in veins.

Back 5

1. Move blood toward the heart. Blood here is under a 3x lower pressure than in the vein 2. Wall made of endothelium, muscle and connective tissue: A. Endothelium (inner layer) is smooth to reduce resistance to blood flow B. The muscle + connective tissue layer (with elastic fibers) is thinner than in arteries, which makes it less strong. The vein does not need to be as strong because the blood it carries is under lower pressure. Also, the thin wall can be pressed flat by adjacent skeletal muscles to help move the blood. C. Muscular wall (thinner than in arteries) contracts rhythmically to help move low-pressure blood through the veins, even if the direction of blood flow is against gravity. However, the skeletal muscles , like your leg muscles, are even more important for this. The study guide even claims that the veins can’t help pump, athough the book disagrees. D. Layer of connective tissue which allows the vein to stretch and recoil. However, this layer is thin because there is little danger o

Front 6

What is atherosclerosis? How does it occur?

Back 6

Disease in which arteries become partially or completely blocked. If the artery is partially blocked, blood flow is reduced so blood pressure is increased. It happens like this… 1. Arteries are damaged 2. Phagocytes travel to the damaged area and release chemical that stimulate the muscles and fibrous tissues in the artery to thicken 3. LDL may enter the damaged cells, causing them to release cholesterol 4. Cholesterol (a lipid) forms a deposit on the inside of the artery (in the lumen)…this is what reduces blood flow. The deposit has a rough surface. 5. The artery becomes less elastic and may harden due to the deposition of calcium salts.

Front 7

What are the possible results of atherosclerosis?

Back 7

1) The rough inner surface of the artery makes blood clots form…this process of forming a clot in a blood vessel is called thrombosis 2) If the clot blocks an artery, blood can’t flow to its normal destination, so part of the body does not get oxygen. This part of the body will become weakened and then die (within 5 minutes). If this happens in the heart it is called a coronary thrombosis (aka heart attack); if it happens in the brain it is called a stroke.

Front 8

What is a thrombosis?

Back 8

A clot in a blood vessel…can block the passage of blood to a part of the body

Front 9

What is a coronary thrombosis? Why is it dangerous?

Back 9

Thrombosis of a coronary artery (artery which supplies blood to the heart). The part of the cardiac muscle heart normally supplied by that artery weakens and stops contracting. This is called a myocardial infarction (or heart attack)

Front 10

What is coronary heart disease?

Back 10

atherosclerosis + coronary thrombosis

Front 11

Discuss the factors that effect the incidence of coronary heart disease

Back 11

Risk factors & explanations: 1. genetic – some people predisposed for high cholesterol levels / high blood pressure; 2. age – older people greater risk / less elasticity in arteries; 3. sex – males at great risk than females; 4. smoking – constricts blood vessels / increases blood pressure/heart-rate / decreases 5. oxygenation of heart muscle; 6. diet – increases fat/cholesterol/LDL in blood / leads to plaque formation in arteries; 7. exercise – lack of exercise increases risk; 8. obesity – increase in blood pressure / leads to plaque formation in arteries

Front 12

Which number on the diagram are arteries? How do you know?

Back 12

1, thick muscular wall, lots of connectiive tissue, no valves, etc

Front 13

Which number on the diagram are veins? How do you know?

Back 13

2, valves present, thinner muscular and connective tissue walls, etc

Front 14

Which number on the diagram are capillaries? How do you know?

Back 14

13, single layer of cells in endothelium, lacks thick muscular and connective tissue wall

Front 15

Which number on the diagram are arterioles?

Back 15

11

Front 16

Which number on the diagram are venules?

Back 16

12

Front 17

Which numbers on the diagram are endothelium?

Back 17

3, 6, 7

Front 18

Which numbers on the diagram are smooth muscle?

Back 18

4, 8

Front 19

Which numbers on the diagram are connective tissue (with elastic fibers)?

Back 19

5, 9

Front 20

Which number on the diagram is a valve?

Back 20

10