What is a noted age-dependent change in the cardiovascular system?

The loss of elasticity in the aorta is a well-documented age-dependent change in the cardiovascular system. As individuals age, the structural proteins within the aorta, primarily elastin and collagen, undergo alterations. The increase in collagen, along with a decrease in elastin, leads to decreased compliance or elasticity of the aortic walls. This results in stiffer arteries, which can contribute to increased systolic blood pressure and a higher workload on the heart.

As other options are considered, increased arterial elasticity would be contrary to well-established findings, as aging typically results in stiffer arteries rather than increased elasticity. Increased cardiac output is also generally not the case; cardiac output may decline or remain unchanged in older adults due to decreased heart rate and other factors, rather than an increase. Decreased heart rate, while it does occur in some aged individuals, is more variable and not a defining characteristic of aging across all populations. Therefore, the noted age-dependent change in the cardiovascular system leading to the correct answer is the loss of elasticity in the aorta, highlighting the important shift in vascular compliance that occurs with aging.