What Has The Greatest Effect On Speed Of Blood Flow?


Arterioles have the most increase in resistance and cause the largest decrease in blood pressure. The constriction of arterioles increases resistance, which causes a decrease in blood flow to downstream capillaries and a larger decrease in blood pressure.

Which has the greatest effect on blood viscosity?

The addition of formed elements to plasma (red cells, white cells, and platelets) further increases the viscosity. Of these formed elements, red cells have the greatest effect on viscosity. In the figure, the relative viscosity at 0% hematocrit (plasma without cells) is about 1.8 as shown by the y-intercept.

What has the greatest effect on peripheral resistance?

Radius of the arterioles is the most important factor, affecting vascular resistance, and it is regulated by systemic and local factors: Systemic factors include: Arterial baroreflex control (increased BP leads to a decrease in SVR. Peripheral and central chemoreceptors (hypoxia leads to increased SVR)

What increases vascular resistance?

Vasoconstriction (i.e., decrease in blood vessel diameter) increases SVR, whereas vasodilation (increase in diameter) decreases SVR.

Which is the most important factor that influences local blood flow?

Peripheral resistance is the most important factor influencing local blood flow, because vasoconstriction or vasodilation can dramatically alter local blood flow, while systemic blood pressure remains unchanged.

What increases the viscosity of blood?

Increased blood viscosity can be caused by an increase in red cell mass or increased red cell deformity, increased plasma levels of fibrinogen and coagulation factors, and dehydration.

Does dehydration increase blood viscosity?

Research published in the journal Aviation, Space, and Environmental Medicine demonstrated that dehydration increases systolic blood viscosity by 9.3% and diastolic blood viscosity by 12.5%.

What liquid has the same viscosity as blood?

The main ingredients of your final recipe probably consisted of corn syrup diluted with water and thickened with flour. This particular mixture resembles the flow of blood quite well because it has a similar viscosity, or resistance to flow.

Which blood vessels experience the sharpest decrease in blood pressure?

The greatest drop in blood pressure occurs at the transition from arteries to arterioles. Primary function of each type of blood vessel: Arterioles have a very small diameter (<0.5 mm), a small lumen, and a relatively thick tunica media that is composed almost entirely of smooth muscle, with little elastic tissue.

Which of the following is directly proportional to blood flow?

Which of the following is directly proportional to blood flow? You correctly answered: blood vessel radius and pressure gradient.

How do you increase arterial blood flow?

In addition, trying one or more of the following may help improve circulation:

  1. Maintaining a healthy weight. Maintaining a healthy weight helps promote good circulation. …
  2. Jogging. …
  3. Practicing yoga. …
  4. Eating oily fish. …
  5. Drinking tea. …
  6. Keeping iron levels balanced.

Where is blood flow the fastest?

This value is inversely related to the total cross-sectional area of the blood vessel and also differs per cross-section, because in normal condition the blood flow has laminar characteristics. For this reason, the blood flow velocity is the fastest in the middle of the vessel and slowest at the vessel wall.


What two factors will increase blood flow?

It is by elevation of stroke volume or heart rate or both. This will increase the blood pressure and enhance the flow of blood. Such factors are sympathetic stimulation, the catecholamines norepinephrine and epinephrine, increased levels of calcium ions, and thyroid hormones.

Where is blood pressure the highest?

Blood flows through our body because of a difference in pressure. Our blood pressure is highest at the start of its journey from our heart – when it enters the aorta – and it is lowest at the end of its journey along progressively smaller branches of arteries.

Does water reduce blood viscosity?

Physicians recommend a high water intake to prevent cerebral infarction by decreasing blood viscosity. However, there is no evidence that high water intake decreases viscosity, although it increases urinary frequency.

What affects the viscosity of blood?

Hematocrit values, plasma fibrinogen levels, and erythrocyte deformability are well-recognized factors affecting blood viscosity.

How does dehydration affect blood flow?

When you are dehydrated your blood volume, or the amount of blood circulating through your body, decreases. To compensate, your heart beats faster, increasing your heart rate and your blood pressure.

What happens to blood pressure when blood viscosity increases?

The relationship between BP and viscosity is such that, given a constant systolic BP, if blood viscosity increases, then the total peripheral resistance (TPR) will necessarily increase, thereby reducing blood flow. Conversely, when viscosity decreases, blood flow and perfusion will increase.

What is a normal blood viscosity reading?

Blood is a non-Newtonian, shear thinning fluid with thixotropic and viscoelastic properties. Many cardiovascular handbooks consider blood viscosity values between 3.5 and 5.5 cP to be normal.

What happens to the body when blood flow is interfered?

In a heart attack (or myocardial infarction), the heart muscle becomes damaged by lack of oxygen, and unless blood flow returns within minutes, muscle damage increases and the heart’s ability to pump blood is compromised. If the clot can be dissolved within a few hours, damage to the heart can be reduced.

What are the three important sources of resistance to blood flow?

There are three primary factors that determine the resistance to blood flow within a single vessel: vessel diameter (or radius), vessel length, and viscosity of the blood. Of these three factors, the most important quantitatively and physiologically is vessel diameter.

What is the most significant source of blood flow resistance?

The correct answer is option (c) blood viscosity. Blood viscosity is the most significant source of blood flow resistance.