Question

Which of the following are NOT the age-related physiological changes?

• A. Reduction in size of slow twitch Type I fibres
• B. Loss of motor neurons
• C. Reduction in size of fast twitch Type II fibres
• D. Increase in non-contractile tissue
• E.

Hint:

Age-related changes in muscle fibers and neurons contribute to reduced strength and coordination as we get older.

Answer 1

The Correct Option is D

Step 1: Understanding age-related physiological changes.
As we age, several physiological changes occur in muscle fibers, motor neurons, and connective tissues, including a reduction in muscle mass, fiber size, and the number of motor neurons.
Step 2: Analyzing each option.
- (1) Reduction in size of slow twitch Type I fibres: Correct. As people age, Type I fibers, which are responsible for endurance and low-intensity activities, reduce in size.
- (2) Loss of motor neurons: Correct. Aging leads to a loss of motor neurons, which affects muscle function and coordination.
- (3) Reduction in size of fast twitch Type II fibres: Correct. Fast twitch fibers, which are responsible for quick, powerful movements, also reduce in size with age.
- (4) Increase in non-contractile tissue: Incorrect. Non-contractile tissue, such as fat and connective tissue, increases with age, but this is not typically considered a normal physiological change related to aging in the same sense as muscle and neuron changes.
Step 3: Conclusion.
The correct answer is (4), as the increase in non-contractile tissue is not typically considered a physiological change related to aging in muscle function.