What is the most important force driving filtration at the arterial end of a capillary quizlet?
The most important force driving filtration at the arterial end of a capillary is blood hydrostatic pressure. Widespread vasodilation does not contribute to venous return.
What is taken up by capillaries at their venous end?
Capillaries connect the arteries to veins. The arteries deliver the oxygen-rich blood to the capillaries, where the actual exchange of oxygen and carbon dioxide occurs. The capillaries then deliver the waste-rich blood to the veins for transport back to the lungs and heart. Veins carry the blood back to the heart.
What is the most important meaning which capillary exchange occurs?
The two principle means of accomplishing this are diffusion and filtration. While simple diffusion is the quantitatively most important form of capillary exchange activity for the respiratory gases, water flux across the blood-brain barrier is facilitated via preformed specialized channels, the aquaporines.
Which of the following would not promote reabsorption from the venous end of the capillary bed?
hydrostatic pressure will rise as blood moves away from the arteriole end of the capillary bed. Which of the following would not promote reabsorption from the venous end of the capillary bed? d. reducing solute concentration in the nearby interstitial fluid.
What decreases capillary filtration rate?
A reduction in the interstitial oncotic pressure increases the net oncotic pressure across the capillary endothelium (πC – πi), which opposes filtration and promotes reabsorption thereby serving as a mechanism to limit capillary filtration.
Why does exercise increase venous return quizlet?
Exercise increases venous return because: the increase in respiratory rate and depth inhibits the action of the thoracic pump. muscle contractions decrease venous return by means of the skeletal muscle pump. blood vessels of the skeletal muscles, lungs, and coronary circulation dilate, increasing flow.
What is hydrostatic pressure in capillaries?
The pressure that blood exerts in the capillaries is known as blood pressure. The force of hydrostatic pressure means that as blood moves along the capillary, fluid moves out through its pores and into the interstitial space.
What happens to the excess fluid that leaves the capillaries at the venous end?
What happens to the excess fluid that leaves the capillaries at the venous end? The excess fluid is collected in the lymphatic capillaries. All veins carry oxygen-poor blood.
What is the main force that causes fluids to enter the venous end of a capillary?
The force of hydrostatic pressure means that as blood moves along the capillary, fluid moves out through its pores and into the interstitial space. This movement means that the pressure exerted by the blood will become lower, as the blood moves along the capillary, from the arterial to the venous end.
What are the two major forces involved in capillary exchange?
hydrostatic pressure: A pressure generated by fluid on the walls of the capillary, usually forcing water out of the circulatory system. net filtration pressure: The balance of the four Starling forces that determines the net flow of fluid across the capillary membrane.
Why does reabsorption occur at the Venule end of a capillary?
2:394:26Capillary Exchange and Edema, Animation – YouTubeYouTube
What is capillary reabsorption?
Reabsorption, the influx of tissue fluid into the capillaries, is driven by the BCOP. Filtration predominates in the arterial end of the capillary; in the middle section, the opposing pressures are virtually identical so there is no net exchange, whereas reabsorption predominates at the venule end of the capillary.
What contributes to venous return?
Venous return is facilitated by a number of factors, including inspiration, increased total blood volume, increased venomotor tone, the cardiac suction effect, the presence of venous valves and the skeletal muscle pump.
What increases venous return?
Respiration – During inspiration, venous return increases as the thoracic cavity's pressure becomes more negative. This reduced intrathoracic pressure draws more blood into the right atrium. This results in greater venous return. Venous Compliance – Increased sympathetic activity will reduce venous compliance.
Why is water reabsorbed at the venous end of the capillary?
Near the venous end of the capillary, the CHP has dwindled to about 18 mm Hg due to loss of fluid. Because the BCOP remains steady at 25 mm Hg, water is drawn into the capillary, that is, reabsorption occurs.
Why is hydrostatic pressure important?
Hydrostatic pressure is one reason (along with the lack of oxygen) why it's not safe for humans to travel unprotected in space. You rely on hydrostatic pressure to keep your lungs at the right inflation and to keep the water in your body from vaporizing.
What pressure causes the water to enter the venous side of the capillary quizlet?
When is the net hydrostatic pressure greater than the net osmotic pressure? More water enters the venous end of a capillary than leaves the arterial end of a capillary. The greater the osmotic pressure of a fluid, the greater the tendency for water to move out of that fluid.
What is reabsorption in capillaries?
Reabsorption, the influx of tissue fluid into the capillaries, is driven by the BCOP. Filtration predominates in the arterial end of the capillary; in the middle section, the opposing pressures are virtually identical so there is no net exchange, whereas reabsorption predominates at the venule end of the capillary.
What factors contribute to venous return to the heart quizlet?
Terms in this set (5)
- Pressure Gradient. most important factor of venous return. …
- Thoracic Pump. respiratory pump. …
- Cardiac Suction. During ventricular systole, a slight suction is created in the atria as the cordae tendinae pull on the AV valve cusps.
- Skeletal Muscle Pump. …
- Gravity.
What vein is responsible for venous return?
0:533:48Mechanisms of Venous Return, Animation – YouTubeYouTube
What is venous hydrostatic pressure?
The force of hydrostatic pressure means that as blood moves along the capillary, fluid moves out through its pores and into the interstitial space. This movement means that the pressure exerted by the blood will become lower, as the blood moves along the capillary, from the arterial to the venous end.
What causes hydrostatic pressure in capillaries?
Hydrostatic pressure in blood vessels is caused by the weight of the blood above it in the vessels. Hydrostatic pressure is the pressure exerted by a fluid at a given point, due to the weight of the fluid above it. Blood is a fluid, so blood has a hydrostatic pressure.
What is the main force that causes fluids to enter the venous end of capillary?
The force of hydrostatic pressure means that as blood moves along the capillary, fluid moves out through its pores and into the interstitial space. This movement means that the pressure exerted by the blood will become lower, as the blood moves along the capillary, from the arterial to the venous end.
Which pressure is highest at the arterial end of any capillary bed?
the net filtration pressure of the blood is higher at the arterial end than it is at the venous end. The fluids reenter the capillaries at the venous end because… the net filtration pressure of the blood is higher at the arterial end than it is at the venous end.
What factor assists venous return to the heart?
Gravity helps the blood return to the heart from the upper body. When muscles contract and relax, they press on nearby veins, causing a pumping effect and squeezing the blood towards the heart. A thin layer of smooth muscle in the veins helps squeeze blood back towards the heart.
What is the force exerted by blood against the wall of a blood vessel?
Pressure is a measure of the force that the blood exerts against the vessel walls as it moves the blood through the vessels. Like all fluids, blood flows from a high pressure area to a region with lower pressure. Blood flows in the same direction as the decreasing pressure gradient: arteries to capillaries to veins.
What influences venous return?
Venous return is facilitated by a number of factors, including inspiration, increased total blood volume, increased venomotor tone, the cardiac suction effect, the presence of venous valves and the skeletal muscle pump.
What causes hydrostatic pressure in the capillaries?
Hydrostatic pressure in blood vessels is caused by the weight of the blood above it in the vessels. Hydrostatic pressure is the pressure exerted by a fluid at a given point, due to the weight of the fluid above it. Blood is a fluid, so blood has a hydrostatic pressure.
Which of the following forces tend to drive water into a capillary?
The primary force driving fluid transport between the capillaries and tissues is hydrostatic pressure, which can be defined as the pressure of any fluid enclosed in a space.
What force drives reabsorption?
The net pressure that drives reabsorption—the movement of fluid from the interstitial fluid back into the capillaries—is called osmotic pressure (sometimes referred to as oncotic pressure). Whereas hydrostatic pressure forces fluid out of the capillary, osmotic pressure draws fluid back in.