bl213 exam 2 (bones terms and cells)

feedback loop for high blood calcium?

feedback loop for low blood calcium?

What is average balance range of calcium in the body?

9-11 mg / 100 mL blood

How much of calcium is in blood?

99%

below 9 mg of calcium is

hypocalcemia *Seizures, spasms

above 11 mg of calcium is

hypercalcemia *Vomiting, kidney stones

traits of cartilage?

Avascular & no nerves, terrible at healing, strong but flexible

3 types of cartilage

hyaline, fibro, elastic

Mesenchymal stem cells

stem cells that copies itself through mitosis, a copy, and an original.

They can become osteoblasts, chondrocytes, adipocytes,

Found in cartilage

OSTEOGENIC CELLS 

Created by mesenchymal cells, the osteogenic cells create new bone associated cells. 

OSTEOBLASTS

Osteoblasts secrete osteoid, the building blocks of bone. 

OSTEOCYTES 

Osteoblasts that got stuck, they live in mature bone. They serve a maintenance function where they help maintain mineralized matrix from inside the bone. (LIVE INSIDE BONE)

 mesenchymal cells -> become osteogenic cells (osteoprogeniter) (produce other bone cell types) -> osteoblasts bone builders that secrete osteoid, if they become trapped they become osteocytes -> osteocytes maintain the bone and function, and maintain matrix from inside the bone (where they are trapped) -> Osteoclasts are another cell, they chew bone and break it down for repair or growth or maintaining. 

process of bone cells lol

appositional

interstitial

two types of bone

compact and spongy

traits of compact bone

Filled tightly with mineralized extracellular matrix leaving very little open space, save for microscopic channels and cell spaces.

traits of spongy bone

made of trabeculae tissue, the hollow spaces are for red marrow, a very vascular substance where blood is produced.

microscopic compact bone anatomy

• Basic building unit (osteon) 

• Osteon look like circles, each having a central canal where blood vessels use (Haversian canals)

• Haversian’s are connected by Volkmann’s (perforating canals) 

osteon

(Haversian systems): Organized into functional cylindrical columns that run parallel to the long axis of the bone to handle stress.

lacunae

Tiny cavities within the solid matrix that house mature bone cells called osteocytes.

canaliculi

Miniature canals that connect lacunae together, allowing nutrient and waste transport through the dense matrix

Hematopoiesis

production of blood, only done by spongy bone. 

lamellae

(individual rings,) the collagen fibers making up these tissue run in the opposite direction (slanted and opposing each layer) in order to resist twisting forces

Inorganic resists?

 compression (heavy weight)

organic material in bone resists?

tension (moreso pulling on the bone)