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HW/ ch 20
Anatomy and Physiology = Bio 2020; CH 20
Term | Definition |
---|---|
The two pairs of major veins that drain the blood from the head and neck are the external and internal jugular veins. | True |
The cephalic, cystic, and brachial veins are responsible for draining most of the blood from the upper limbs. | False |
The median cubital vein is often used as a site for drawing blood from a patient. | True |
Capillary exchange is the process by which cells receive everything they need to survive and to eliminate metabolic waste. | True |
By far the most important means by which capillary exchange occurs is filtration. | False |
A small amount of fluid moves out of capillaries at their venous ends, and most of that fluid reenters the capillaries at their arterial ends | False |
Filtration pressure is the force responsible for moving fluid across capillary walls. | True |
Edema can be caused a result of which event(s)? | Hypertension, causing an increase in tissue fluid at the arteriolar ends of capillaries. Increased tissue protein concentration, causing a decrease in osmosis of interstitial fluid into capillaries. |
Edema can be caused a result of which event(s)? cont. | Decreased plasma protein concentration, causing a decrease in osmosis of interstitial fluid into capillaries. Obstruction of lymphatic vessels, blocking lymphatic drainage. |
In both pulmonary and systemic circulation, gas exchange occurs at the | capillaries |
Blood pressure is highest in the ___________ and lowest in the _____________. | arteries closest to the heart, veins |
Capillaries have only a | tunica intima |
The vessels that are responsible for carrying blood away from the heart are | arteries. |
Under the microscope, the wall of a blood vessel is observed to contain only a tunica intima. This must be a(n) | capillary. |
During exercise, blood is shifted from the __________ into systemic circulation. | veins |
Under the microscope, a blood vessel is observed to have a relatively thin wall, a large lumen, is collapsed, and contains a thick tunica externa. This is probably a(n) | vein. |
Four main arterial branches emerge from the aortic arch. | False |
If blood flow in the capillaries was too fast, there might not be sufficient time for exchange of nutrients and waste between tissues and blood. | True |
Hyaline cartilage has a low degree of vascularization. This means that | blood delivery to this tissue is limited. |
The thyroid gland is highly perfused. Therefore, it has a ______ degree of vascularization. | high |
When a vessel is damaged, local prostaglandins may be released and cause vasodilation to help prevent further blood loss. | False |
Local control of blood flow is achieved by the periodic relaxation and contraction of precapillary sphincters regulating blood flow through the tissues | True |
Precapillary sphincters relax as the tissue concentration of nutrients, such as oxygen, glucose, amino acids, and fatty acids, increases. | False |
Vasodilator substances are produced in the extracellular fluid as the rate of metabolism increases. | True |
During inflammation, __________ may be released and act as a vasodilator. | histamine |
Which vessel drains capillaries? | Postcapillary venules |
Deoxygenated blood from the heart myocardium drains into the right atrium via the | coronary sinus. |
Vasodilation | increases blood flow and decreases blood pressure. |