The innermost layer of blood vessel walls made up of one layer of endothelium and in direct contact with the blood is:
1. tunica adventitia | 2. tunica intima |
3. tunica media | 4. tunica muscularis |
Blood vessels have smooth muscles in their walls that are innervated by:
1. myelinated motor neurons.
2. unmyelinated sympathetic neurons.
3. unmyelinated motor neurons.
4. unmyelinated parasympathetic neurons.
The build-up of fats, cholesterol and other substances in and on the artery walls is known as:
1. | arteriosclerosis | 2. | atherosclerosis |
3. | aneurysm | 4. | anastomosis |
The smoothness of endothelium is a very important factor that prevents thrombus formation. The endothelial cells:
1. increase cardiac output.
2. decrease heart rate.
3. inhibit platelet aggregation and control blood vessel diameter.
4. nourish the cells in the outer half of the blood vessel wall.
Capillary walls are different from the walls of veins and arteries as they are composed of:
1. endothelium only.
2. endothelium and smooth muscle.
3. a tunica interna and a tunica media.
4. smooth muscle and elastic connective tissue.
The right ventricle pumps the blood into the pulmonary trunk that next enters the:
1. pulmonary veins.
2. left and right pulmonary arteries.
3. pulmonary capillaries.
4. left atrium
Branch of aorta that supplies the oxygenated blood to the muscles of the heart is:
1. coronary arteries.
2. common carotid arteries.
3. coronary sinus.
4. great cardiac veins.
Identify the incorrect statement regarding the hepatic portal system:
1. It includes two capillary beds separated by a portal vein.
2. The first capillary bed picks up nutrients from the liver.
3. The second capillary bed delivers nutrients to the liver.
4. Blood leaving the hepatic portal vein flows into the second capillary bed.
What factor is responsible for the movement of the blood in the vascular system?
1. valves in the walls of the blood vessels.
2. peristalsis caused by the smooth muscle in the blood vessel walls.
3. pressure gradients created by the heart.
4. osmotic pressure.
Venous return to the heart would be increased when there is:
1. dilation of the veins.
2. loss of the venous valves.
3. increased skeletal muscle activity.
4. decreased respiratory rate