Which two aspects of the cardiovascular system are noted to decrease with age?

Which two aspects of the cardiovascular system are noted to decrease with age?

• A. Blood volume and bone marrow activity
• B. Blood volume and heart rate
• C. Bone marrow activity and stroke volume
• D. Blood volume and capillary density

Answer: (A)

As people age, the circulating component of the cardiovascular system and its blood-forming capacity tend to decline, which affects overall circulation and oxygen delivery. Blood volume decreases because plasma volume shrinks with aging, hydration changes, and reduced production of plasma proteins. Bone marrow activity also declines with age, leading to lower production of red cells, white cells, and platelets. That combination means there is less circulating blood and fewer blood cells to carry oxygen and fight infection, contributing to reduced cardiovascular reserve and slower adaptation to stress. Other options involve factors like heart rate or capillary density. While those can change with age in ways that affect cardiovascular function, the most consistently noted decreases linked to aging in this context are blood volume and bone marrow activity.

As people age, the circulating component of the cardiovascular system and its blood-forming capacity tend to decline, which affects overall circulation and oxygen delivery. Blood volume decreases because plasma volume shrinks with aging, hydration changes, and reduced production of plasma proteins. Bone marrow activity also declines with age, leading to lower production of red cells, white cells, and platelets. That combination means there is less circulating blood and fewer blood cells to carry oxygen and fight infection, contributing to reduced cardiovascular reserve and slower adaptation to stress.

Other options involve factors like heart rate or capillary density. While those can change with age in ways that affect cardiovascular function, the most consistently noted decreases linked to aging in this context are blood volume and bone marrow activity.