During exercise, venous return is enhanced by?

Question

a.the operation of carotid arterialand femoral arterial valves.
b. the operation of the respiratory muscle/ventilation pump.
c. skeletal muscle pump operation.
d. all of the above.
e. only b & c.
I'm torn between D and E. help me out a little?

Answer 1

The correct answer is E, only b & c.

During exercise, venous return is enhanced by the operation of the respiratory muscle/ventilation pump and the skeletal muscle pump.

The respiratory muscle/ventilation pump works by creating negative pressure in the thoracic cavity during inhalation, which helps to pull venous blood back towards the heart. During exhalation, the pressure in the thoracic cavity increases, which helps to push blood out of the veins and towards the heart.

The skeletal muscle pump works by the rhythmic contraction and relaxation of skeletal muscles, which helps to squeeze blood in the veins towards the heart. As the muscles contract, they compress the veins, which increases the pressure and helps to push blood towards the heart. As the muscles relax, the veins are allowed to fill with blood, which reduces pressure and creates a vacuum that helps to pull more blood towards the heart.

The operation of carotid arterial and femoral arterial valves is not directly involved in enhancing venous return during exercise.

Answer 2

The answer is C because when our veins reach our feet, and lower limbs, their ability to get the blood ALLLLLL the way back to the heart is aided by pumping those muscles! That is why it is so important when a patient is in the hospital for example that they have sequential compression on their lower limbs, that is doing the squeezing that our muscles normally would be doing. Our calf muscle, for example, is surrounded by a tough sheath (called fasica) and when it presses against this, the pressure helps move fluid back up the veins. The veins have valves, so the blood can't leak back down, but we need to be contracting or feet and legs, preferably weight bearing, or on the ground with our body weight, like walking, to really help the muscles work harder to push and squeeze the blood back up the veins to the heart.

Answer 3

D. venous pressure is about 3-5mmHg. Venous blood circulates by 2 mechanism, compression by skeletal muscle, and the negative pressure created in the thoracic cavity on inspiration.

(valves only exist in the venous system and are isolated to the legs, these are one-way valves, and there are more in the left leg

Dr. George Boyd

Answer 4

the answer is "e". During exercise the skeletal muscles contract and compress the veins which pusses blood from the veins towards the heart and the valves inside the veins prevent the back flow during relaxation of the muscles. Also the ventilation increases during exercise and the respiratory muscles work more.

Answer 5

As the question is presented, the correct answer is "e" as there are not valves in the arterial system to prevent back-flow of blood. The answer, however, would become "all of the above" had the question been proposed as "femoral and arterial veins" as these are operated by muscle pumping and pressure gradients to improve blood flow back towards the heart.

Answer 6

The best answer is "D" with a little editing, the valves are found in veins, not arteries , but to complete the answer all the systems work together to increase blood flow during exercise, the answer "e" is most correct since there are valves in veins only. A hint from an experienced test WRITER, always read the question carefully, test writers include inaccuracies to test your knowledge of the topic, example valves found in arteries your knowledge is being tested to see if you "fall for the answer "D", when you should realize that there aren't valves in arteries, now ask yourself why aren't there valves in arteries, the answer lie in the anatomy of the artery versus the vein . Arteries have a smooth muscle layer inside them and veins lack the muscle layer. The venous valves help to prevent back flow of the blood. This is just a partial explanation , to find out more you will need to explore the anatomy and physiology of the circulatory system. From your question it sounds as though you already have. Remember , read test questions carefully

Answer 7

the venous return enhanced by contraction off lower limb muscles and valves in the veins not arteries 

Answer 8

I want to say E because I know there are valves in veins that prevent backflow, not arteries.