11 Physio Muscle Joint

What is the role of mitochondria in muscle fibers?

• To store calcium

• To produce ATP

• To contract the muscle

• To generate nerve impulses

How many nuclei do skeletal muscle fibers typically have?

• One

• Two

• Multiple

• None

What do bones and exoskeletons provide for muscles?

• Elasticity

• Anchorage and leverage

• Nutrients

• Oxygen supply

Which proteins control muscle contractions?

• Hemoglobin and myoglobin

• Actin and myosin

• Tropomyosin and troponin

• Keratin and elastin

Which joints allow movement in multiple directions?

• Fixed joints

• Hinge joints

• Ball and socket joints

• Pivot joints

What is the primary component of myofibrils?

• Lipids

• Contractile sarcomeres

• Glycogen

• ATP

What is necessary for the sliding of filaments in muscle contraction?

• Glucose breakdown

• ATP hydrolysis and cross-bridge formation

• Oxygen intake

• Carbon dioxide release

In what arrangement do muscles work in the body?

• In parallel pairs

• In antagonistic pairs

• Independently

• In identical pairs

What is the main function of the fulcrum in a lever system?

• To provide a pivot point

• To apply force

• To resist movement

• To act as a counterweight

What happens to the Z-lines during muscle contraction?

• They move apart

• They move closer together

• They disappear

• They stay the same distance apart