Muscles

Muscle Fiber: What is a muscle fiber?

• A. A connective tissue that binds muscles together

• B. An individual muscle cell

• C. The outer covering of a muscle

• D. A protein that helps in muscle contraction

Motor End Plate: The motor end plate is found:

• A. At the junction between a motor neuron and a muscle fiber

• B. Inside the nucleus of a muscle cell

• C. Within the sarcoplasmic reticulum

• D. At the end of a myofibril

Myofibril: Myofibrils are:

• A. The connective tissues surrounding muscles

• B. The contractile elements within muscle cells

• C. Nerve cells that stimulate muscles

• D. The membranes surrounding muscle fibers

Myosin: Myosin is a:

• A. Thin filament protein involved in muscle contraction

• B. Thick filament protein involved in muscle contraction

• C. Type of motor neuron

• D. Type of muscle cell

Actin: Actin is a:

• Thick filament protein involved in muscle contraction

• Type of connective Tissue

• Thin Filament protein involved in muscle contraction

• Structural component of motor neurons

Sarcolemma: The sarcolemma is:

• The cytoplasm of a muscle cell

• A protein involved in muscle contraction

• 
  

  The membrane surrounding a muscle fiber

  
  

• The connective tissue around muscle bundles

. A-band: The A-band in a sarcomere:

• - A. Contains only actin filaments

• - B. Contains only myosin filaments

• - C. Contains both actin and myosin filaments

• - D. Is the light band in a sarcomere

I-band: The I-band in a sarcomere:

• - A. Contains only myosin filaments

• - B. Contains only actin filaments

• - C. Contains both actin and myosin filaments

• - D. Is the dark band in a sarcomere

Z-line: The Z-line in a sarcomere:

• - A. Marks the boundary between adjacent sarcomeres

• - B. Is the center of the A-band

• - C. Contains only myosin filaments

• - D. Is the region where actin overlaps myosin

M-line: The M-line in a sarcomere:

• - A. Is the center of the I-band

• - B. Contains only actin filaments

• - C. Is the center of the A-band and contains proteins that hold myosin filaments in place

• - D. Marks the boundary between adjacent sarcomeres