Muscle Anatomy and Basic Contraction Questions

What is a myogram?

• A chart that shows the number of muscle fibers in a motor unit

• A recording of the events of a muscle twitch

• A measurement of muscle tone

• A recording of the amount of movement resulting from a skeletal muscle contraction

What causes the striated appearance of skeletal muscle fibers?

• Arrangement of transverse tubules

• Position of the sarcoplasmic reticulum network

• Organization of components of the sarcomeres

• Location of the cisternae

What term describes the more movable end of a muscle?

• Origin

• Fulcrum

• Insertion

• Source

What is the linea alba?

• A muscle extending from the ischial spine to the coccyx and sacrum

• A curved, broad muscle on the side of the chest

• A strip of tough connective tissue covering the top of the cranium

• A band of tough connective tissue on the midline of the abdomen

Which connective tissue layer is comprised of loose connective tissue?

• Perimysium

• Fascia

• Epimysium

• Endomysium

What neurotransmitter(s) can stimulate smooth muscle cells?

• Both norepinephrine and acetylcholine

• Only norepinephrine

• Only acetylcholine

• Only calcium

During a muscle contraction, why is ATP required?

• To synthesize creatine phosphate

• To breakdown glycogen into glucose for fuel

• To allow myofilament movement

• To stimulate enzyme activity

What binds to the exposed cross-bridges on actin?

• ATP

• Myosin

• Calcium

• Acetylcholine

What features are not present in smooth muscle?

• Actin and myosin

• Transverse tubules and striations

• Myofibrils

• Nuclei and mitochondria

What type of muscle cells lack transverse tubules, have a single nucleus, and are under involuntary control?

• Skeletal muscle

• Smooth muscle

• Cardiac muscle