Skeletal Muscle Structure QuizOnline version Test your knowledge on the components of skeletal muscle fibers! by Ahmed Elmowafy 1 What are myofibrils primarily composed of? a Nucleic acids b Carbohydrates c Contractile proteins (microfilaments) d Lipids 2 What is the role of the sarcoplasmic reticulum in muscle fibers? a Produces ATP b Transports oxygen c Stores and releases Ca++ for contraction d Synthesizes proteins 3 Where are mitochondria located in skeletal muscle fibers? a In the cytoplasm only b At the cell membrane c Near the nucleus, between myofibrils d In the Golgi apparatus 4 What pigment gives skeletal muscle its red-brown color? a Hemoglobin b Chlorophyll c Carotene d Myoglobin 5 What is a key function of glycogen in skeletal muscle? a Oxygen transport b Energy storage c Protein synthesis d Calcium storage 6 What type of cellular structure is a Golgi associated with in muscle fibers? a One nuclear pole b Myofibrils c Sarcoplasmic reticulum d Mitochondria 7 What is the primary function of the sarcoplasm in muscle fibers? a Stores genetic material b Transports nutrients c Contains organelles and substances for muscle function d Produces hormones 8 What is the shape of myofibrils in skeletal muscle? a Irregular and branched b Short and spherical c Flat and sheet-like d Long, parallel cylindrical structures 9 What does the sarcoplasmic reticulum release during muscle contraction? a Potassium ions b Sodium ions c Chloride ions d Calcium ions (Ca++) 10 Which organelle is responsible for energy production in muscle fibers? a Golgi apparatus b Nucleus c Endoplasmic reticulum d Mitochondria