Muscles of the Upper Lip, Back, and Buttocks Anatomy Quiz

Muscles of the Face

• The zygomaticus major muscle elevates the angle of the mouth and exposes the maxillary teeth.
• The buccinator muscle compresses the cheek and raises the jaw.

Muscles of the Back and Buttocks

• The trapezius muscle extends the head and scapula, and raises the scapula.
• The levator scapula muscle retracts the scapula.
• The rhomboid muscle retracts the scapula.
• The erector spinae muscle maintains the erect posture of the vertebral column.
• The gluteus medius muscle abducts the thigh and medially rotates it.
• The gluteus maximus muscle extends the hip joint.

Muscles of the Thorax and Abdomen

• The pectoralis major muscle controls the movement of the arms, adducts and medially rotates the arm, depresses the scapula, and protracts the scapula.
• The pectoralis minor muscle compresses the abdomen.
• The serratus anterior muscle compresses the abdomen.
• The external abdominal obliques muscle compresses the abdomen.
• The internal abdominal obliques muscle compresses the abdomen.
• The rectus abdominis muscle compresses the abdomen.
• The transverse abdominal muscle compresses the abdomen.
• The scalene muscle raises the ribs and expands the thorax.
• The external intercostal muscle expands the thorax.

Muscles of the Arm

• The deltoid muscle abducts the arm.
• The biceps brachii muscle flexes the elbow and supinates the arm.
• The brachialis muscle flexes the elbow.
• The brachioradialis muscle flexes the arm.
• The supraspinatus muscle extends the shoulder.
• The infraspinatus muscle rotates the arm.

Muscles of the Thigh (Anterior)

• The iliopsoas muscle flexes the hip.
• The sartorius muscle flexes the thigh and laterally rotates it.
• The quadriceps femoris muscle extends the knee.
• The rectus femoris muscle extends the knee.
• The vastus lateralis muscle extends the knee.
• The vastus intermedius muscle extends the knee.
• The vastus medialis muscle extends the knee.

Muscles of the Leg

• The gastrocnemius muscle plantar flexes the foot.
• The soleus muscle plantar flexes the foot.
• The peroneus/fibularis muscle plantar flexes and everts the foot.
• The tibialis anterior muscle dorsiflexes the foot and inverts the foot.

Muscles of the Thigh (Posterior)

• The hamstrings muscle (biceps femoris, semitendinosus, and semimembranosus) extends the thigh and flexes the knee.

Muscles of the Pelvic Floor and Perineum

• The levator ani muscle constricts the anus, urethra, and vagina.
• The ischiocavernosus muscle resists increased erection.
• The bulbospongiosus muscle aids in urine and semen expulsion.

Muscular System

• Major organs and structures: muscles.
• Accessory structures: tendons.
• Functions: movement, maintain posture, respiration, production of body heat, communication, heart beat, and contraction of organs and vessels.

Properties of Muscles

• Control: voluntary or involuntary.
• Location: skeletal or cardiac.
• Striated or non-striated.

Anatomical Terms

• Intrinsic muscle: origin and insertion located in the same body region.
• Extrinsic muscle: origin in a different body region and insertion.
• Fixator: holds an origin stable for another muscle.
• Synergists: muscles with the same action.
• Prime mover: main muscle of the synergists.
• Antagonist: muscle with an opposing action.

Muscle Actions

• Flexion: bends a part of the body anteriorly.
• Extension: bends a part of the body posteriorly.
• Abduction: moves a part of the body away from the midline.
• Adduction: moves a part of the body towards the midline.
• Protraction: brings a part of the body forward.
• Retraction: brings a part of the body backward.
• Circumduction: makes a circle with part of the body.
• Lateral excursion: moves the jaw laterally to either side.
• Medial excursion: moves the jaw medially.