Name at least three muscles that actively contract during the following activities and name their action and innervation:
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Turning a door knob
Muscle: Supinator
Action: Supinates forearm at the radioulnar joints.
Innervation: Deep radial nerve.
Muscle: Brachioradialis
Action: Flexes forearm at the elbow joint and supinates and pronates forearm at radioulnar joints to a neutral position.
Innervation: Radial nerve.
Muscle: Biceps Brachii
Action: Flexes forearm at the elbow joint, supinates forearm at radioulnar joints, and flexes the arm at the shoulder joint.
Innervation: Musculocutaneous nerve.
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Throwing a baseball overhead
Muscle: Teres Major
Action: Extends arm at the shoulder joint and assists in adduction and medial rotation of the arm at the shoulder joint.
Innervation: Lower subscapular nerve.
Muscle: Subscapularis
Action: Medially rotates arm at the shoulder joint.
Innervation: Upper and lower subscapular nerve.
Muscle: Deltoid
Action: Lateral fibers abduct the arm at the shoulder joint. Anterior fibers flex and medially rotate the arm at the shoulder joint. Posterior fibers extend and laterally rotate the arm at the shoulder joint.
Innervation: Axillary nerve.
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Kicking a ball
Muscle: Quadriceps
Action: Extend the leg at the knee joint
Innervation: Femoral nerve
Muscle: Iliopsoas
Action: Flex thigh at hip joint, rotate thigh laterally, and flex trunk on hip.
Innervation: Lumbar spinal nerves (L2 - L3)
Muscle: Rectus Femoris
Action: Extend leg at knee joint; flexes thigh at the hip joint.
Innervation: Femoral nerve.
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Doing sit-ups
Muscle: Rectus abdominis
Action: Flexes the vertebral column in addition to compressing the abdominal wall
Innervation: Thoracoabdominal muscles.
Muscle: Transverse abdominis
Action: Compresses the abdomen.
Innervation: Thoracic spinal nerves T8 - T12, iliohypogastric nerve, and ilioinguinal nerve.
Muscle: Internal Obliques
Action: Help rotates the trunk.
Innervation: The internal oblique is innervated by both the lower intercostal nerves as well as branches of the lumbar plexus (iliohypogastric nerve and ilioinguinal nerve).
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Walking
Muscle: Soleus
Action: It is a powerful plantar flexor and is a major postural muscle that stabilizes the body.
Innervation: Tibial nerve
Muscle: Gastrocnemius
Action: Plantar flexes foot at the ankle joint and flexes leg at the knee joint.
Innervation: Tibial Nerve.
Muscle: Quadriceps
Action: Extends and straightens the knee.
Innervation: Femoral nerve.
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Breathing
Muscle: Diaphragm
Action: Contraction of the diaphragm causes it to flatten and this increases the vertical dimension of the thoracic cavity, resulting in inhalation. Relaxation of the diaphragm causes it to move superiorly and decreases the vertical dimension of the thoracic cavity, resulting in exhalation.
Innervation: Phrenic nerve (including axons from cervical spinal nerves C3 - C5.
Muscle: Internal Intercostals
Action: Elevates ribs and increases anteroposterior and lateral dimensions of the thoracic cavity during contraction; depresses ribs and decreases anteroposterior and lateral dimensions of the thoracic cavity during relaxation.
Innervation: Thoracic spinal nerves T2 - T12.
Muscle: External Intercostals
Action: Draws adjacent ribs together to further decrease anteroposterior and lateral dimensions of the thoracic cavity during forced exhalation.
Innervation: Thoracic spinal nerves T2 - T12.