Bone Anatomy and Structure Terms

Cheese hehehe

epiphysis

the end of a long bone; proximal or distal depending on where it is attached to the body

diaphysis

the shaft of a long bone

osteocytes

mature bone cells that are found in the web of the bone matrix

endosteum

lines the medullary cavity

hyaline cartilage

Forms much of the fetal skeleton and covers the articular surfaces of long bones

articular cartilage

padding between bones; at the ends of the bones

periosteum

membrane that covers entire bone

spongy bone

type of bone found in the epiphysis; also called cancellous bone

Hematopoeisis

formation of blood cells and occurs in the bone marrow

Compact bone

dense, hard layers of bone tissue that lie underneath the periosteum membrane; contains calcium and phosphorus minerals

Yellow marrow

soft, fatty material found in the medullary cavity of long bones

Osteoblasts

Bone building cells; lay the bone matrix

Erythropoietin (EPO)

hormone secreted by the kidney to stimulate the production of red blood cells by bone marrow

osteoclasts

break down bone to release calcium into the bloodstream

epiphyseal line/plate

between diaphysis and epiphysis of an adult bone. A disc of hyaline cartilage that grows during childhood to lengthen bone.

Red marrow

found in the epiphysis of long bones; where red blood cells are produced.

What are the inorganic and organic components of bone? Which one provides strength and which provides flexibility?

Organic: Collagen fibers- provide flexibility
Inorganic: Calcium salts- provide strength

Rickets (osteomalacia of children)

during bone development (usually seen in kids), a lack of calcium and/or vitamin D can lead to a deficiency in calcium in the bone. Osteomalacia is the general term for soft bones.

Purpose of bone marrow

Hematopoiesis - blood cell production (RBC, WBC, Platelets) occurs in the red bone marrow. Also serves as
Fat storage (yellow bone marrow)

Hormone that stimulates red blood cell formation

erythropoietin

Hormone that stimulates growth plate to divide and bones to lengthen?

Growth Hormone

What is another name for the growth plate?

epiphyseal plate

What type of tissue is the growth plate made of?

hyaline cartilage

What is the growth plate called after the tissue ossifies (hardens) and lengthens when adult height is reached?

Epiphyseal line

Where do osteoblasts originate?

osteoprogenitor (stem) cells in the periosteum

How do osteoblasts become osteocytes?

osteoblasts get trapped in the bone matrix they secrete (or lay down)

Why do osteoclasts break down bone?

to reabsorb bone and release calcium minerals back in the bloodstream

Name the hormone that stimulates osteoclasts.

Parathyroid hormone (PTH) stimulates osteoclasts to break down bone when the body senses blood calcium levels are too low.

What type of feedback mechanism is the regulation of blood calcium levels?

Negative Feedback

What happens to the bone matrix, over time, if blood calcium levels are always low? Name the condition.

The body will stimulate osteoclasts to break down the compact bone to release calcium leading to osteoporosis (porous bone).

The joint capsule is continuous with which membrane?

periosteum