Anatomy & Physiology Study Guide: Skeletal and Muscular Systems

Axial Skeleton

Skull

The skull is composed of several bones that protect the brain and form the structure of the face. Students should be able to identify the listed bones and features on an articulated skull, excluding the auditory ossicles and mandible.

• Frontal bone

• Parietal bone (2)

• Temporal bone (2)

  • Zygomatic process

  • Mastoid process

  • External acoustic meatus

  • Styloid process

  • Petrous part

  • Internal acoustic meatus

  • Jugular foramen

  • Carotid canal

• Occipital bone

  • Foramen magnum

  • Occipital condyle (bilateral)

  • External occipital protuberance

• Sphenoid bone

  • Sella turcica

  • Greater wing (bilateral)

  • Lesser wing (bilateral)

  • Optic canal (bilateral)

  • Pterygoid process (bilateral)

• Ethmoid bone

  • Cribriform plate (bilateral) with cribriform foramina

  • Crista galli

  • Perpendicular plate

  • Middle nasal concha (bilateral)

Cranial Sutures

• Coronal suture

• Sagittal suture

• Squamous suture (bilateral)

• Lambdoid suture

Facial Bones

• Maxilla (2)

  • Alveolar process

  • Dental alveolus (8)

  • Palatine process

  • Temporal process

• Mandible

  • Mandibular body

  • Mandibular ramus (bilateral)

  • Mandibular angle (bilateral)

  • Condyloid process (bilateral)

  • Mandibular notch (bilateral)

  • Coronoid process (bilateral)

  • Alveolar process

  • Dental alveolus (16)

  • Mandibular foramen (bilateral)

  • Mental foramen (bilateral)

• Lacrimal (2)

• Palatine (2)

• Inferior nasal concha (2)

• Vomer (1)

Other Skull Structures

• Temporomandibular joint

• Zygomatic arch (bilateral)

• Orbit (bilateral)

• Hard palate (bilateral)

• Nasal septum

• Auditory ossicles (3 sets of 2)

• Paranasal sinuses: Frontal sinus, Ethmoid sinus, Maxillary sinus, Sphenoid sinus

• Hyoid bone (1)

Vertebral Column

Vertebrae

The vertebral column consists of cervical, thoracic, lumbar, sacral, and coccygeal vertebrae. Each vertebra has distinct features for identification.

• Cervical vertebrae (7)

  • Atlas (C1) and Axis (C2) with dens

  • Body

  • Vertebral foramen

  • Transverse process (bilateral)

  • Spinous process (not on atlas)

  • Superior/inferior articular processes and facets

• Thoracic vertebrae (12)

  • Superior/inferior costal facets

  • Body

  • Vertebral foramen

  • Transverse process (bilateral)

  • Spinous process

  • Superior/inferior articular processes and facets

• Lumbar vertebrae (5)

  • Body

  • Vertebral foramen

  • Transverse process (bilateral)

  • Spinous process

  • Superior/inferior articular processes and facets

• Sacrum (1)

• Coccyx (1)

Thoracic Cage

• Thoracic vertebrae (12)

• Sternum (1): Manubrium, Body, Xiphoid process

• Ribs (12 pairs): True ribs (1-7), False ribs (8-12), Floating ribs (11-12)

• Costal cartilage

Appendicular Skeleton

Shoulder Girdle

• Scapula (2): Spine, Acromion, Coracoid process, Glenoid cavity, Supraspinous fossa, Infraspinous fossa, Subscapular fossa

• Clavicle (2): Sternal end, Acromial end

Upper Limb

• Humerus (2): Head, Anatomical neck, Greater tubercle, Lesser tubercle, Intertubercular sulcus, Surgical neck, Deltoid tuberosity, Olecranon fossa, Trochlea, Capitulum, Medial/lateral epicondyle

• Ulna (2): Olecranon process, Trochlear notch, Coronoid process, Radial notch, Styloid process

• Radius (2): Head, Neck, Radial tuberosity, Styloid process

• Carpals (2 sets of 8)

• Metacarpals (2 sets of 5)

• Phalanges (2 sets of 14)

Pelvic Girdle

• Coxal bone (2): Ilium, Ischium, Pubis, Acetabulum, Obturator foramen, Iliac crest, Anterior superior iliac spine, Greater sciatic notch, Ischial tuberosity, Ischial spine, Pubic symphysis

• Pelvis: Coxal bones, Sacrum, Coccyx

Lower Limb

• Femur (2): Head, Neck, Greater/lesser trochanter, Gluteal tuberosity, Lateral/medial condyle, Lateral/medial epicondyle

• Patella (2)

• Tibia (2): Tibial tuberosity, Medial/lateral condyle, Medial malleolus

• Fibula (2): Lateral malleolus

• Tarsals (2 sets of 7)

• Metatarsals (2 sets of 5)

• Phalanges (2 sets of 14)

Joints and Ligaments

• Patellar ligament

• Medial/lateral collateral ligament

• Anterior cruciate ligament

• Posterior cruciate ligament

Muscular System

Muscles of Mastication (Chewing)

• Masseter: Elevates the mandible

• Temporalis: Elevates and retracts the mandible

• Medial pterygoid: Synergist with masseter and temporalis; side-to-side grinding movement; protracts mandible

• Buccinator: Compresses cheek (whistling/sucking)

• Sternocleidomastoid: Origin: Manubrium of sternum and medial clavicle; Insertion: Mastoid process of temporal bone; Action: Flexes and laterally rotates the head

Muscles of the Thorax and Shoulder

• Pectoralis Major: Origin: Sternum, clavicle, and costal cartilages; Insertion: Greater tubercle of humerus; Action: Flexes, adducts, and medially rotates arm

• Deltoid: Origin: Clavicle and upper limb model; Action: Abducts arm

• Trapezius: Origin: Occipital bone, spines of thoracic vertebrae; Insertion: Lateral third of clavicle, acromion, spine of scapula; Action: Stabilizes, elevates, depresses, and retracts scapula; extends head

• Latissimus Dorsi: Origin: Spines of lower six thoracic vertebrae, lumbar vertebrae, lower four ribs, iliac crest; Insertion: Intertubercular sulcus of humerus; Action: Extends, adducts, and medially rotates arm

Muscles of the Abdominal Wall

• Rectus Abdominis: Not responsible for origin, insertion, or action

• External Oblique: Not responsible for origin, insertion, or action

Rotator Cuff Muscles

• Supraspinatus

• Infraspinatus

• Subscapularis

• Teres minor

• Group action: Holds head of humerus in glenoid cavity, stabilizing shoulder joint

Muscles of the Upper Limb

• Biceps Brachii: Use Helga and upper limb model

• Brachialis: Use Helga and upper limb model

• Triceps Brachii: Use Helga and upper limb model

• Brachioradialis: Use Helga and upper limb model

Muscles of the Lower Limb

• Gluteus Maximus: Origin: Dorsal ilium, sacrum, coccyx; Insertion: Gluteal tuberosity of femur, iliotibial tract; Action: Extends thigh, laterally rotates and abducts thigh

• Adductor group: Know as a group only

• Sartorius: Origin: Anterior superior iliac spine; Insertion: Medial surface of proximal tibia; Action: Flexes thigh, rotates thigh laterally

• Quadriceps femoris group: Know as a group only; Action: Extends leg

• Hamstring group: Know as a group only; Action: Flexes leg, extends thigh

• Tibialis anterior: Origin: Proximal two-thirds of tibia; Insertion: Tarsal and metatarsal; Action: Dorsiflexion of foot

• Gastrocnemius: Origin: Lateral and medial condyles of femur; Insertion: Posterior calcaneus via calcaneal tendon; Action: Plantar flexes foot, flexes leg

• Calcaneal tendon: Use Helga and lower limb model

Key Terms and Definitions

• Foramen: An opening or hole in a bone for passage of nerves and blood vessels

• Process: A projection or outgrowth of bone

• Condyle: A rounded articular projection

• Fossa: A shallow depression in bone

• Suture: An immovable joint between skull bones

• Facet: A smooth, flat surface for articulation

Summary Table: Major Bone Groups and Features

Bone Group	Key Features
Skull	Frontal, Parietal, Temporal, Occipital, Sphenoid, Ethmoid, Mandible, Maxilla, Zygomatic, Nasal, Lacrimal, Palatine, Vomer, Inferior nasal concha
Vertebral Column	Cervical (7), Thoracic (12), Lumbar (5), Sacrum, Coccyx
Thoracic Cage	Sternum, Ribs (True, False, Floating), Costal cartilage
Shoulder Girdle	Scapula, Clavicle
Upper Limb	Humerus, Ulna, Radius, Carpals, Metacarpals, Phalanges
Pelvic Girdle	Ilium, Ischium, Pubis, Acetabulum, Obturator foramen
Lower Limb	Femur, Patella, Tibia, Fibula, Tarsals, Metatarsals, Phalanges

Additional info:

• Some muscle origins, insertions, and actions are not required for memorization; refer to models as indicated.

• Use anatomical models (Helga, PAL) for practical identification.

• Paranasal sinuses include frontal, ethmoid, maxillary, and sphenoid sinuses.

• Auditory ossicles are the malleus, incus, and stapes (3 sets of 2).

• For muscle groups (e.g., quadriceps, hamstrings, adductors), know the group action rather than individual muscle details unless specified.