Hesi A2 A&P: Bones

What are the main functions of the skeletal system?

protection

support

movement

hemopoiesis

mineral storage

detoxification

hormone regulation

What are the different types of bone cells and their functions?

• Osteoblasts: Form new bone.

• Osteocytes: Mature bone cells that maintain bone tissue.

• Osteoclasts: Break down and reabsorb bone.

What are the different bone types?

• Long: E.g., femur, humerus (shaft is diaphysis, ends are epiphysis).

• Short: E.g., carpals, tarsals.

• Flat: E.g., ribs, scapulae, skull bones.

• Irregular: E.g., vertebrae.

• Sesamoid: E.g., patella.

What is the tough, connective tissue covering the bone called?

Periosteum

What is the dense, hard outer layer of bone called?

Compact Bone

What is the porous inner layer of bone, located in the epiphysis called?

Spongy Bone

What makes up the axial skeleton?

The skull, the vertebral column, the sternum, and 12 pairs of ribs. (80 bones)

What makes up the appendicular skeleton?

Shoulder (pectoral) girdle, pelvic girdle, and upper and lower extremities (126 bones)

What three things regulate calcium in the body? (non-organ)

• Parathyroid Hormone (PTH): Increases blood calcium by activating osteoclasts.

• Calcitonin: Decreases blood calcium by inhibiting osteoclasts and promoting osteoblasts.

  • Vitamin D: Increases absorption of calcium in the small intestine.

The shaft of a long bone is called

Diaphysis

The end of the long bone is called

Epiphysis

What are common disorders of the skeletal system?

• Osteoporosis: A condition characterized by weakened bones and an increased risk of fractures.

• Arthritis: Inflammation of the joints which can cause pain and stiffness.

• Fractures: Breaks in the bone that can be classified as simple or compound.

• Scoliosis: A lateral curvature of the spine.

• Kyphosis: Forward rounding of the back, also known as hunchback.

What are the major ligaments associated with the skeletal system?

• Anterior cruciate ligament (ACL): Helps stabilize the knee joint.

• Posterior cruciate ligament (PCL): Also stabilizes the knee, preventing backward movement of the tibia.

• Collaterals (medial and lateral): Provide stability to the sides of the knee joint.

How do bones heal after a fracture?

• Inflammation: Hematoma forms at the fracture site.

• Soft Callus Formation: Cartilage is formed to bridge the fracture gap.

• Hard Callus Formation: Bone tissue replaces the soft callus.

  • Remodeling: The bone is reshaped and remodeled over time to restore its original structure.

What are the major bones in the chest&torso?

Ribs, sternum, and clavicles

What are the major bones in the arms?

Humerus (upper arm), Radius, Ulna (forearm), the carpals, metacarpals, and phalanges

What are the major bones in the legs

Femur (thigh), Tibia (shin), Fibula (calf), Patella (kneecap), tarsals, metatarsals, and phalanges

Major bones in the back?

Vertebrae, Sacrum, and Coccyx (tailbone)

What are the major bones in the girdles?

Scapula (shoulder blade)

Pelvis (hip bones: ilium, ischium, pubis)

What is the only movable bone in the skull?

The mandible