Bone Structure and Function Quiz

Bone Structure and Function

• Bones protect internal organs like the brain (skull) and spinal cord (vertebral column)
• Bones store and release fats (yellow bone marrow) and minerals (calcium, phosphorus)
• Bones produce blood cells (red bone marrow)
• Bones facilitate movement by providing attachment points for muscles and creating scaffolding for the body
• Bone marrow, a connective tissue, is found inside most bones
• Yellow bone marrow stores fat (adipocytes) and energy (triglycerides)
• Red bone marrow produces blood cells (hematopoiesis) like RBCs (Red Blood Cells), WBCs (White Blood Cells), and platelets.

Bone Marrow

• Yellow bone marrow stores fat for energy.
• Red bone marrow produces blood cells (red blood cells, white blood cells, platelets)

Parts of a Long Bone

• Epiphysis: the end of a long bone, articulates with another bone to form a joint (covered with hyaline cartilage).
• Articular cartilage: covers the epiphysis, allowing smooth joint movement.
• Metaphysis: region where the epiphyseal plate (growth plate) is located
• Diaphysis: the shaft of the long bone
• Periosteum: a tough, vascular covering of tissue
• Medullary cavity: the hollow chamber within the diaphysis (contains bone marrow)

Classification of Bones

• Bones are classified by shape, including long (e.g., femur, humerus), short (e.g., carpals, tarsals), flat (e.g., sternum, ribs), irregular (e.g., vertebrae), and sesamoid (e.g., patella). Each bone type has a specific function related to its shape.

Compact vs. Spongy Bone

• Compact bone: Dense, tightly packed tissue, continuous extracellular matrix. Found in diaphysis of long bones.
• Spongy bone: Irregular thin bony plates (trabeculae), highly developed to resist compressive forces and reduce weight. Found in epiphysis of long bones.

Bone Matrix

• Osseous tissue (bone tissue): connective tissue that supports osteocytes (bone forming cells), providing structure and flexibility.
• The matrix is composed of 1/3rd collagen fibers and 2/3rd calcium and phosphate salt.
• Collagen provides flexibility and framework, while calcium phosphate provides hardness and strength

Bone Cells

• Osteogenic cells: stem cells that differentiate into osteoblasts.
• Osteoblasts: form the bone matrix by secreting collagen that is subsequently mineralized.
• Osteocytes: mature bone cells that maintain bone tissue.
• Osteoclasts: reabsorb (break down) old bone tissue.

Paget's Disease

• Disorder of bone remodeling process
• Patients usually over 40 years old
• Overactive osteoclasts
• Bones are prone to fractures, and symptoms include pain, bone deformities, and frequent fractures

Bone Fractures

• Open fractures: the fractured bone breaks through the skin
• Closed fractures: the fractured bone remains within the skin but out of alignment
• Reduction: manipulating the bone back into alignment
• Open reduction: Requires surgery
• Closed reduction: Does not require surgery

Fracture Repair

• Direct bone healing: osteoblasts and osteoclasts unite broken structures by direct contact, forming new bone
• Indirect bone healing: cartilaginous patches form between broken bones before regeneration begins.

Test your knowledge on the structure and function of bones, including the role of bone marrow in blood cell production and energy storage. This quiz covers key concepts such as epiphysis, cartilage, and the different types of bone marrow.