Understanding the Muscular System

What is the primary function of tendons in the muscular system?

• Connect muscle to muscle

• Connect muscle to bone

• Connect bone to bone

• Connect skin to muscle

Which of the following best describes fascia in the muscular system?

• A type of muscle fiber

• A neurotransmitter

• A sheet of densely packed collagen fibers

• A type of bone tissue

What type of muscle is responsible for voluntary movements and is striated?

• Cardiac muscle

• Smooth muscle

• Skeletal muscle

• Involuntary muscle

What are the two main types of filaments that make up myofibrils in skeletal muscle fibers?

• Actin and myosin

• Collagen and elastin

• Keratin and fibrin

• Tropomyosin and troponin

What is the functional unit of a skeletal muscle called?

• Myofibril

• Sarcomere

• Sarcoplasmic reticulum

• Myosin head

Which neurotransmitter is responsible for creating an action potential on the muscle?

• Dopamine

• Serotonin

• Acetylcholine

• Norepinephrine

• They bind to myosin heads

• They bind to troponin on the thin actin filament

• They provide energy for ATP synthesis

• They break down acetylcholine

What happens when calcium ions bind to troponin during muscle contraction?

• Troponin releases calcium ions

• Tropomyosin moves to make space for myosin head attachment

• Myosin heads detach from actin filaments

• ATP is synthesized

What is the role of ATP in muscle contraction?

• It binds to actin filaments

• It provides energy for myosin heads to bind to actin filaments

• It stores calcium ions

• It breaks down acetylcholine

Which structure in the muscle fiber stores and releases calcium ions during muscle contraction?

• Myofibril

• Sarcomere

• Sarcoplasmic reticulum

• Tropomyosin