Exploring the Muscular System

What is the main function of the muscular system?

• To produce hormones

• To protect internal organs

• To store energy

• To produce movement

Which muscle group is responsible for opposing the action of the prime movers?

• Fixators

• Agonists

• Antagonists

• Synergists

What type of muscle tissue is striated and contracts involuntarily?

• Visceral muscle

• Skeletal muscle

• Smooth muscle

• Cardiac muscle

What is the role of myofibrils in muscle cells?

• To contract the muscle

• To store calcium

• To produce ATP

• To transport oxygen

Which protein blocks the binding sites on actin in a relaxed muscle?

• Tropomyosin

• Troponin

• Myosin

• Actin

What triggers the release of calcium ions from the sarcoplasmic reticulum?

• Muscle relaxation

• ATP binding

• Myosin head movement

• Action potential

What is the role of acetylcholine in muscle contraction?

• To block actin binding sites

• To release calcium ions

• To transmit nerve signals

• To provide energy

Where are the somatic motor neurons that activate skeletal muscle fibers mainly located?

• Brain

• Muscles

• Heart

• Spinal cord

What is a lever in the context of the human body?

• A muscle

• A type of bone

• A joint

• A rigid bar that moves on a fixed point

Which type of lever has the fulcrum between the effort and the load?

• Fourth class lever

• Third class lever

• Second class lever

• First class lever