Human Body Systems

An increase in blood volume will cause a decrease in blood pressure.

• true

• false

• both

Answer explanation

An increase in blood volume typically raises blood pressure due to more fluid exerting pressure on blood vessel walls. Therefore, the statement is false.

A decrease in blood pressure will cause a decrease in blood flow.

• true

• false

Answer explanation

True. A decrease in blood pressure reduces the pressure gradient driving blood flow, leading to decreased blood flow to tissues and organs.

An increase in blood viscosity will cause a decrease in blood flow.

• true

• false

Answer explanation

True. An increase in blood viscosity makes it thicker, which increases resistance to flow. This resistance reduces blood flow, confirming that higher viscosity leads to decreased blood flow.

An increase in blood vessel diameter will cause a decrease in blood flow.

• true

• false

Answer explanation

An increase in blood vessel diameter (vasodilation) actually leads to increased blood flow due to reduced resistance. Therefore, the statement is false.

A decrease in viscosity will cause an increase in blood flow.

• true

• false

Answer explanation

True. A decrease in viscosity means blood flows more easily, reducing resistance in the vessels, which leads to an increase in blood flow.

Patient A has a higher cholesterol than patient B, patient A is at a lower risk of heart disease.

• true

• false

Answer explanation

Higher cholesterol levels typically indicate a greater risk of heart disease. Therefore, the statement that Patient A, with higher cholesterol, is at a lower risk is false.

Patient A has been diagnosed with cardiovascular disease caused by plaque. Patient A's arteries have a decreased flow of blood.

• true

• false

Answer explanation

True is correct because cardiovascular disease caused by plaque leads to narrowed arteries, which decreases blood flow.

Cardiovascular disease runs in Jim’s mother’s family. Jim is only 17 but knows that his mom and grandparents all have high blood pressure. Which of the following best describes the connection between cardiovascular disease and age?

• As people age, plaque builds up in the arteries increasing vessel resistance, which leads to disease.

• As people age, their blood vessels become more elastic leading to less cardiovascular disease.

• As people age, the heart becomes more efficient with each pump, increasing cardiac output.

• As people age, blood pressure decreases leading to more cardiovascular disease.

Answer explanation

As people age, plaque builds up in the arteries, increasing vessel resistance and leading to cardiovascular disease. This explains the connection between age and the risk of developing such diseases.

The rate at which blood flows through the human body changes in response to many factors. Which statement describes one of these factors and its effect on blood flow?

• A high viscosity of blood causes an increased resistance in the blood vessels and leads to slow blood flow.

• A low blood pH decreases the rate of diffusion through the blood vessels and leads to slow blood flow.

• The changing of the shape of red blood cells to a crescent shape decreases resistance and lead to a faster blood flow.

• The narrowing of blood vessels increases pressure and leads to a faster blood flow.

Answer explanation

A high viscosity of blood increases resistance in blood vessels, which slows down blood flow. This is the correct choice as it accurately describes how blood viscosity affects circulation.

The illustration below shows four lobes of the human brain. What lobe is designated by label 1?

• occipital

• temporal

• parietal

• frontal

Answer explanation

Label 1 designates the occipital lobe, which is located at the back of the brain and is primarily responsible for visual processing.