1. (a) Biceps brachii
action: flexes forearm at elbow joint, supinates forearm at radioulnar joints, and flexes arm at shoulder joint
innervation: musculocutaneous nerve
(b) Deltoid
action: lateral fibers abduct arm at shoulder joint; anterior fibers flex and medially rotate arm at shoulder joint; posterior fibers extend and laterally rotate arm at shoulder joint
innervation: axillary nerve
2. (a) Tibialis anterior
action: dorsiflexes and inverts foot
innervation: deep fibular (peroneal) nerve
(b) Gastrocnemius
action: plantar flexes foot, flexes leg at knee joint
innervation: tibial nerve
3. (a) Rectus abdominis
action: flexes lumbar region of vertebral column, produce forward bending of waist
innervation: thoracic spinal nerves (T7-T12)
(b) Iliopsoas
action: hip flexor, psoas major and iliacus muscles acting together flex thigh at hip joint, rotate thigh laterally, and flex trunk on hip as in sitting up from supine position
innervation: lumbar spinal nerves (L2-L3)
4. (a) Internal Intercostals
action: contraction draws adjacent ribs together to further decrease anteroposterior and lateral dimensions of thoracic cavity during forced exhalation
innervation: thoracic spinal nerves (T2-T12)
(b) Diaphragm
action: increases and decreases vertical dimension of thoracic cavity by contracting and relaxing (inhaling and exhaling, respectively)
innervation: phrenic nerves containing axons from cervical spinal nerves (C3-C5)
Reference:
Tortora, G. J. & Derrickson, B. (2017). Principles of anatomy & physiology (15th ed.).