fascicles

Examples of fascicles in the following topics:

• Arrangement of Fascicles

  • Skeletal muscles are grouped into fascicles, which are bunches of muscle fibers surrounded by a perimysium.
  • It extends inwards and becomes the perimysium, then into the muscle separating muscle fibers into small bundles termed fascicles.
  • Fascicles can be arranged in a variety of anatomical positions within a muscle, producing different movements.
  • Within this is a layer termed the epimysium which splits inwards into the muscle as the perimysium dividing muscle fibers into groups termed fascicle.
  • Each fascicle is surrounded by another layer of connective tissue termed the endomysium.

• How Skeletal Muscles Are Named

  • The anatomical arrangement of skeletal muscle fascicles can be described as parallel, convergent, pennate, or sphincter.
  • Because the fascicles pull on the tendons at an angle, they do not move the tendon as far as their parallel muscle counterparts.
  • Fascicles pull on the tendon at an angle, thus not moving as far at the parallel muscles during a contraction.
  • If all the fascicles of a pennate muscle are on the same side of the tendon, the pennate muscle is called unipennate.
  • If the fascicles lie to either side of the tendon the muscle is called bipennate.

• Axon Bundles

  • Each nerve consisting  of many fascicles is covered externally by a dense sheath of connective tissue, the epineurium.
  • Underlying this layer of flat cells, the perineurium, forms a complete sleeve around a bundle of axons called fascicles.

• Blood Flow in Skeletal Muscle

  • Blood vessels are closely intertwined with skeletal muscle tissues lying between the fascicles, or bundles of muscle fibers, with each muscle supplied by many capillaries.
  • Skeletal muscle: 1] Bone, 2] Perimysium, 3] Blood vessel, 4] Muscle fiber, 5] Fascicle, 6] Endomysium, and 7] Epimysium Tendon.

• Structure of a Nerve

  • The axons are bundled together into groups called fascicles.
  • Each fascicle is wrapped in a layer of connective tissue called the perineurium.

• Skeletal Muscle Fibers

  • They are bound together by perimysium, a sheath of connective tissue, into bundles called fascicles, which are in turn bundled together to form muscle tissue.

• Muscle Development

  • These cells remain adjacent to a muscle fiber, situated between the sarcolemma and the endomysium (the connective tissue investment that divides the muscle fascicles into individual fibers).