Question

Give a brief description of the different factors that contribute to blood circulation

Answer 1

The blood circulatory system distributes nutrients and oxygen to all the cells of body.

· It consist of heart and blood vessels.

· Arteries and veins.

· Arteries carry blood away from heart.

· Veins carries blood form he cells to back o he heart.

· The systemic circulatory system circulates oxygenated blood from the heart around the blood to tissues before back to deoxygenated blood to heart.

Three main factors are here hat can influence t blood circulation.

Ø Resistance

Ø Blood pressure

Ø Blood flow

Broadly which influence on blood pressure the factors are

Ø Cardiac output

Ø Peripheral résistance

Ø Volume of circulating blood

Ø Viscosity of blood

Ø Elasticity of blood

Resistance: to flow must be overcome to push blood in to the circulatory system.

If resistance increases, pressure must increase to maintain flow which mainly depends on vessel length, vessel radius, blood viscosity.

With increasing length, increasing viscosity, decreasing radius, so here by increases radius.

The arterioles and capillary networks are main regions for circulatory systems. Which generate resistance, due to small space of the lumen.

Blood pressure: the pressure hat blood exerts on the wall of the blood vessels.

The pressure originates in the contraction of the heart. Which forces blood out from the heart and into the vessels.

If flow is impaired through increased resistance blood pressure must increase, so blood pressure is of en used as a test for circulatory health. Blood pressure can be modulated through altering cardiac activity, vasoconstriction or vasodilatation.

Blood flow: flow the movement of the blood around the circulatory system. A relatively constant flow is required by the body issues, so pressure and resistance are alerted his to maintain consistency. High flow can damage blood vessels, while low flow means tissue no sufficient oxygen supplied to cell.