Final Exam Chapter 15 review Flashcards
Which is more elastic, veins or arteries? WHY???
Arteries are because they need to withstand the high pressure of blood pumped directly from the heart. THEY ARE ALWAYS UNDER CONSTANT PRESSURE.
Veins are less elastic so they can hold a very high percentage of the blood in circulation
Explain elastic rebound in the large arteries
When the ventricle pushes the blood out the artery walls stretch because of the pressure (cushions the pressure during ventricular systole). Then when the ventricle relaxes (ventricular diastole) and there is no more pressure. Then it causes the artery walls to snap back (un stretch) and it sends a huge force in the artery to get the blood to the rest of the body.
How does elastic rebound affect systolic blood pressure?
It lowers systolic blood pressure
How does elastic rebound affect diastolic blood pressure?
It raises diastolic pressure
What would happen to the systolic and diastolic pressure if there was less elastic rebound in the arteries? (the walls are stiffer)
Systolic pressure would be increased and the diastolic pressure would be decreased
What causes varicose veins? (4) And what is it?
Sitting and standing in one place for long periods of time, pregnancy, obesity pressures or it is heredity
It is where blood pools in the leg veins stretching the walls and the valves no longer work
How do the skeletal muscle pump and the respiratory pump work?
Skeletal muscle pump: you push blood up to the heart when your muscle contracts. Then when it is relaxed the blood comes back down but the valves in the veins close so it doesn’t go down farther and negate the work it made getting it up to the heart. So it goes from valve to valve every time a muscle contracts and relaxes until it reaches the heart. (same thing with respiratory pump)
Respiratory pump: Same thing as the skeletal muscle pump but when you inhale and exhale
How does erythropoietin affect blood pressure?
It causes vasoconstriction and production of red blood cells and it causes an INCREASES BLOOD PRESSURE
Explain what blood colloid osmotic pressure (BCOP) is.
An attracting pressure caused by Albumin in the capillaries that attracts Na+ ions and water back into the capillary REABSORBS (-25mmHg)
What is the role of albumin with regards to net filtration pressure?
It attracts Na+ ions which attracts water and reabsorbs it back into the capillaries
What blood vessels are most responsible for vascular resistance? WHY?
Arterioles, because they are so small
How does vascular resistance affect blood pressure in the largest arteries?
Basically arteries are wide, then the blood flows to the distribution arteries which are narrower and slow down (back pressure increases, and resistance), and then you get to the arterioles which are even narrower and increases back pressure and resistance.
More resistance = higher blood pressure
How does aldosterone affect blood pressure?
INCREASES BLOOD PRESSURE by keeping sodium in the kidneys and constricts arterioles
How does ADH hormone affect blood pressure?
It does vasoconstriction by reabsorbing water from the kidneys and INCREASES BLOOD PRESSURE
What role does nitric oxide have in autoregulation of blood flow?
It dilates the blood vessels
