9. Glycolytic skeletal muscle fibers...

A. demonstrate higher resistance to fatigue than oxidative fibers.

B. have a smaller diameter than oxidative fibers

C. have a higher density of mitochondria than oxidative fibers

D. have a lower concentration of myoglobin than oxidative fibers

The correct answer is D.

Explanation:      

Glycolytic skeletal muscle fibers are also called fast glycolytic muscle fibers. The produce Adenosine triphosphate (ATP) very quickly.

ATP refer to the molecule that carries energy inside our cells. It is also known as a high-energy molecule that warehouses energy and supplies the cell with it when it is required.

Because Glycolytic muscle fibers contain larges units of glycogen, they are able to respond very quickly by producing tension fast.

Unlike other skeletal muscle fibres such as the slow and fast oxidative fibres, Glycolytic muscle fibers contain myoglobin and seem to be white in colour. This is because they do not require the anaerobic mechanism to generate the required energy.  

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