Factors Affecting Blood Flow

Factors Affecting Blood Flow

SC.912.L.14.36

Describe the factors affecting blood flow through the cardiovascular system. 

Vocab Words

• Cardiovascular Disease: conditions affecting the overall health of the human body due to factors that alter the function of components of the cardiovascular system such as the heart and blood vessels

• Cardiovascular System: heart, lungs, blood, and all blood vessels that transport nutrients and wastes throughout the body

Cardiovascular System

• Blood full of oxygen flows from the heart through

• arteries of decreasing size

  capillaries deliver oxygen to cells

  veins return oxygen-poor blood to the heart and lungs

Cardiovascular System

• Blood pressure - heart ventricle contractions create a force, or blood pressure, on arteries.

• Hypertension – high blood pressure – overworks the heart and puts stress on blood vessels

  Very low blood pressure – your cells do not get enough oxygen 

Blood Viscosity

• The thickness of blood!

• Factors that affect the thickness of blood include diabetes, and certain medications

• It increases blood pressure because your heart has to work twice as hard to get the blood through the body!

Multiple Choice

Which of the following describes high blood viscosity?

• There is a high concentration of blood cells and solutes

• The blood is more thick and the heart has to pump harder

• Blood pressure goes up

• All are correct

Blood Pressure

pressure of circulating blood against the walls of blood vessels. 

Normal blood pressure is 120/80

It is not considered to have blood pressure higher than the average for an extended period of time because of the stress it places on your arteries!

Multiple Choice

Which statement best describes blood pressure?

•  The force applied by the heart and amount of blood pumped determine blood pressure.

•  It’s normal and healthy to have extended periods of high blood pressure.

•  Your blood pressure is higher when you sleep. 

•  Being nervous can decrease your blood pressure.

Resistance

Working against the heart!

Factors include:

Sitting in a position that restricts blood flow

Diseases like arteriosclerosis that builds up plaque in the arteries causing blockages and potential clots.

Multiple Choice

When an individual has high cholesterol, certain substances, such as calcium and fats, form plaque in arteries. How is this plaque, known as arterial plaque, most likely to affect blood flow?

• Arterial plaque clogs the arteries, limiting or stopping blood flow.

• Arterial plaque changes the direction of blood flow, which forces oxygenated blood to the heart.

• Arterial plaque changes the size of blood cells, which prevents blood from flowing in the arteries.

• Arterial plaque clears the arteries, increasing blood flow.

Multiple Choice

What is the most likely affect a blood clot will have on blood flow through the cardiovascular system?

• A blood clot will increase blood flow in other areas, allowing more oxygen to reach tissue in those areas.

• A blood clot will change the direction of blood flow, allowing oxygen to reach tissue in a new area.

• A blood clot will not change blood flow, allowing the same amount of oxygen to reach tissue in a certain area.

• A blood clot will block blood flow, preventing oxygen from reaching tissue in a certain area.

Arterial Elasticity!

• Arteries are flexible so that they can withstand fluctuations in pressure. Flexible arteries mean more blood flow, and decreased blood pressure and resistance.

• Hardened arteries have a harder time dealing with flucations in pressure and this can lead to decreaed blood flow and increased blood pressure

Multiple Choice

Elasticity in blood vessels allows the vessels to stretch and move based on changes in blood volume. A number of factors, including genetic disease, can cause the arteries to harden and lose their elasticity. How would the hardening of the arteries most likely affect blood flow?

• The hardening of the arteries would likely cause blood flow to remain constant.

• The hardening of the arteries would likely increase blood flow.

• The hardening of the arteries would likely cause blood flow to stop completely.

• The hardening of the arteries would likely restrict blood flow.

Multiple Choice

Which of the following statements best describes blood flow in the human body?

• As the thickness of the blood decreases, the rate of blood flow increases.

• As the diameter of a blood vessel decreases, the rate of blood flow increases.

• As the length of a vein decreases, the resistance to blood flow decreases

• As blood pressure increases, the rate of blood flow decreases.

Multiple Choice

Which of the following factors decreases blood flow?

• an increase in blood pressure

• an increase in overall blood volume

• a decrease in the radius of a blood vessel

• a decrease in blood viscosity

Multiple Choice

Arteriosclerosis is a disease which clogs arteries in the human body. In arteriosclerosis, artery walls become thick. Fatty deposits build up on inner walls of arteries. This condition reduces the ability of arteries to perform their function. The diagram above shows a comparison between a healthy artery and one with arteriosclerosis. Which body function is most affected by arteriosclerosis? 

• circulating blood to tissues

• assembling amino acids into proteins

• replacing damaged cells with new cells

• breaking down food particles into molecules

Multiple Choice

A doctor prescribes a blood thinner to a patient with high blood pressure. What impact will this medication have on blood flow and viscosity?

• A doctor prescribes a blood thinner to a patient with high blood pressure. What impact will this medication have on blood flow and viscosity?

• The blood flow will decrease and the viscosity will increase.

• The blood flow will increase and the viscosity will decrease

• The blood flow will increase and the viscosity will increase.