part 2 of skeleton Flashcards
Which type of cartilage is found in the intervertebral discs?
c) Fibrocartilage
Which bone cell is responsible for breaking down bone tissue?
c) Osteoclasts
The diaphysis of a long bone contains:
c) Medullary cavity
What hormone stimulates osteoclasts to release calcium into the bloodstream?
c) Parathyroid hormone
Explain the difference between compact bone and spongy bone.
Compact bone is dense and forms the outer layer of bones, while spongy bone is lighter and contains trabeculae.
What are the four stages of fracture healing?
- Hematoma formation 2. Fibrocartilaginous callus formation 3. Bony callus formation 4. Bone remodeling
Why is osteoporosis more common in older adults?
Due to decreased osteoblast activity and hormonal changes.
How do osteoblasts and osteoclasts work together in bone remodeling?
Osteoblasts build new bone while osteoclasts break down old bone.
What is the function of red vs. yellow bone marrow?
Red bone marrow produces blood cells, while yellow bone marrow stores fat.
Name the three types of cartilage and provide an example of where each is found in the body.
Hyaline cartilage – Found in joints, ribs, nose. Elastic cartilage – Found in the ear, epiglottis. Fibrocartilage – Found in intervertebral discs, pubic symphysis.
What are the five major types of bones based on shape? Give an example of each.
Long bones (e.g., femur), Short bones (e.g., carpals), Flat bones (e.g., skull), Irregular bones (e.g., vertebrae), Sesamoid bones (e.g., patella).
Identify the three major parts of a long bone and describe their functions.
Diaphysis – The shaft, provides strength. Epiphysis – The ends, contain spongy bone and red marrow. Metaphysis – Between diaphysis & epiphysis, contains the growth plate.
What is the difference between the axial skeleton and the appendicular skeleton?
Axial Skeleton – Includes the skull, vertebral column, rib cage. Appendicular Skeleton – Includes limbs and girdles.
What are fontanelles, and why are they important in infants?
Soft spots on a baby’s skull that allow for brain growth and easier birth.
Which type of bone cell is found in lacunae and is responsible for maintaining bone health?
Osteocytes
What are trabeculae, and where are they found?
Trabeculae are the network of thin, bony structures in spongy bone, found in epiphyses of long bones.
Which bone in the human body is the largest and strongest?
The femur.
What is the difference between the epiphyseal plate and the epiphyseal line?
Epiphyseal plate – Found in children; allows for bone growth. Epiphyseal line – Found in adults after growth has stopped.
What are the three types of joints in the human body, and how do they differ in mobility?
Fibrous joints – Immovable. Cartilaginous joints – Slightly movable. Synovial joints – Freely movable.
What role does parathyroid hormone (PTH) play in calcium regulation?
PTH increases blood calcium by stimulating osteoclasts to break down bone.
How does calcitonin affect bone remodeling?
Calcitonin lowers blood calcium by inhibiting osteoclast activity and promoting bone deposition.
Explain the process of bone remodeling and why it is important.
Osteoblasts build new bone, while osteoclasts break down old bone. Importance: Prevents fractures, adapts bones to stress.
What is the difference between intramembranous and endochondral ossification?
Intramembranous ossification – Forms flat bones directly from mesenchyme. Endochondral ossification – Forms most bones by replacing cartilage.
Why does bone loss occur with aging, and how can it be prevented?
Cause: Reduced osteoblast activity. Prevention: Weight-bearing exercise, calcium & vitamin D intake.
What happens when calcium levels in the blood become too low?
Parathyroid hormone (PTH) is released, stimulating osteoclasts to break down bone and release calcium.
What type of bone marrow is responsible for hematopoiesis, and where is it primarily found?
Red bone marrow – Found in flat bones and epiphyses of long bones.
What happens during osteoporosis, and which bones are most affected?
Osteoporosis: Bone resorption exceeds deposition. Most affected: Spine, hip, and wrist.
What is the relationship between vitamin D and calcium absorption in bones?
Vitamin D helps the intestines absorb calcium, which is needed for strong bones.
