What is the cytoplasm of a muscle fiber?

What is the cytoplasm of a muscle fiber?

• A. Sarcoplasm
• B. Sarcolemma
• C. Myoglobin
• D. Sarcoplasmic reticulum

Answer: (A)

The term for the cytoplasm of a muscle fiber is sarcoplasm. The sarcoplasm is the fluid and organelles inside the muscle cell, enclosed by the sarcolemma, which is the cell membrane. Within the sarcoplasm lie the myofibrils—the contractile elements—as well as mitochondria, glycogen granules, and myoglobin, which stores oxygen for muscle energy. The sarcoplasmic reticulum is a separate network of tubules that stores and releases calcium to trigger contraction, not the cytoplasm itself. So the cytoplasm of a muscle fiber is the sarcoplasm.

The term for the cytoplasm of a muscle fiber is sarcoplasm. The sarcoplasm is the fluid and organelles inside the muscle cell, enclosed by the sarcolemma, which is the cell membrane. Within the sarcoplasm lie the myofibrils—the contractile elements—as well as mitochondria, glycogen granules, and myoglobin, which stores oxygen for muscle energy. The sarcoplasmic reticulum is a separate network of tubules that stores and releases calcium to trigger contraction, not the cytoplasm itself. So the cytoplasm of a muscle fiber is the sarcoplasm.