ACTIVITY 2

VILLARUEL, Keith Jacob E. – Activity 2

VILLARUEL, Keith Jacob E. – Activity 2

by Keith Jacob Villaruel -
Number of replies: 0

1. Throwing baseball overhead

  • Muscle: Pectoralis Major

    • Action: as a whole adducts and medially rotates arm at shoulder joint; clavicular head flexes arm and sternocostal head extends flexed arm to side of trunk

    • Innervation: medial and lateral pectoral nerves

  • Muscle: Deltoid

    • Action: lateral fibers abduct arm at shoulder joint; anterior fibers flex and medial rotate arm at shoulder joint; posterior fibers extend and laterally rotate arm at shoulder joint

    • Innervation: axillary nerve

 2. Kicking a Ball

  • Muscle: Rectus Femoris

    • Action: all four heads extend leg at knee joint; rectus femoris muscle acting alone also flexes thigh at hip joint

    • Innervation: femoral nerve

  • Muscle: Biceps femoris

    • Action: flexes leg at knee joint and extends thigh at hip joint

    • Innervation: tibial and fibular nerves from sciatic nerve

3. Doing Sit ups 

  • Muscle: Rectus abdominis

    • Action: Flexes vertebral column, especially lumbar portion, and compresses abdomen to aid in defecation, urination, forced exhalation, and childbirth; RMA: flexes pelvis on the vertebral column

    • Innervation: Thoracic spinal nerves T7-T12

  • Muscle: External obliques

    • Action: Acting together (bilaterally), compress abdomen and flex vertebral column, acting singly (unilaterally) , laterally flex vertebral column, especially lumbar portion, and rotate vertebral column

    • Innervation: Thoracic spinal nerves T7-T12 and iliohypogastric nerve 

4. Breathing

  • Muscle: Diaphragm

    • Action: contraction of diaphragm causes it to flatten and increases vertical dimension of thoracic cavity resulting in inhalation; relaxation of diaphragm causes it to move superiorly and decreases vertical dimension of thoracic cavity, resulting in exhalation

    • Innervation: phrenic nerve, which contains axons from cervical spinal nerves C3-C5

 

  • Muscle: External intercostal

    • Action: Contraction elevates ribs and increases anteroposterior and lateral dimensions of thoracic cavity, resulting in inhalation; relaxation depresses ribs and decreases anteroposterior and lateral dimensions of thoracic cavity, resulting in exhalation.

    • Innervation: Thoracic spinal nerves T2–T12.

 

REFERENCE:
Tortora, G. J., & Derrickson, B. (2017). Principles of anatomy & physiology. Fifteenth edition; Wiley Loose-Leaf Print Companion. Hoboken, New Jersey, John Wiley & Sons, Inc.