Anatomy and Physiology II Practice Test

Which of the following is not an effect of aging?

1. Renal mass decreases

2. Respiratory capacity decreases

3. Cardiac output at rest decreases

4. Nerve conduction speed increases

The correct answer is: Nerve conduction speed increases

The statement that nerve conduction speed increases is indeed not an effect of aging. In fact, research shows that as individuals age, there tends to be a decrease in nerve conduction speed. This decline is attributed to various factors, including changes in myelin sheath integrity and decreases in neuron density, which can impact the efficiency of electrical signal transmission throughout the nervous system. In contrast, aging is commonly associated with a decrease in renal mass, respiratory capacity, and cardiac output at rest. As people age, the kidneys may lose nephrons, leading to a reduction in renal mass and function. Similarly, the lungs experience a decrease in elasticity and airway function, resulting in reduced respiratory capacity. The heart also undergoes structural and functional changes that can lead to decreased cardiac output, particularly during times of increased physical activity or stress. Understanding these age-related changes is crucial for recognizing the potential health impacts in older adults.