anatomy and physiology skeleton quiz

bone

rigid organ made up of all 4 types of tissue

connective tissue

the majority is bone (osseous) tissue but cartilage and dense connective tissue cover the bone’s external surface

nervous tissue

in its nerves

epithelial tissue

in its blood vessels, which provide nourishment

muscle tissue

skeletal muscle tissue

how many bones do we have?

206

how much of our weight does our bones make up?

1/5

how many years do we get a whole new skeleton?

7-10 years

what are the functions of the skeletal system?

support, protection, movement, storage, blood cell formation, hormone production

support

Framework holding up the entire body

protection

Guards the body’s most vital organs, like the skull protecting the brain and the rib cage protecting the heart

movement

Skeletal muscles are connected to bones via tendons and use bones at joints to produce movements

storage

Stores minerals like calcium and phosphate, which can be released into the blood when needed. Stores energy in the form of fat in yellow bone marrow

hormone production

Critical for helping to maintain homeostasis

what are the 4 main types of bones?

long, short, flat, irregular

long bone

longer than they are wide, tend to have a long shaft with either end being a bit wider, mostly located in the limbs, act as levers to aid in movement

short bone

more cube shaped, tend to be as wide as they are long, provide support and stability with little movement

sesamoid bone

special type of short bone, means to be shaped like a sesame seed, are embedded within tendons

flat bone

thin and flat bones, often have a bit of a curve, large surface area, attaching to muscles

irregular bone

everything else, have a highly specialized shape and structure

compact bone

primary duty of supporting the body, protects our organs, provides attachment points for muscles and tendons used for movement

spongy bone (cancellous / trabecular bone)

less dense, contains lots of blood vessels, contains red bone marrow where blood cells are made

what are the 3 types of bone marking?

projections, surfaces, depressions & opening

projections

where muscle and ligaments attach

surfaces

that form joints

depressions and openings

for blood vessels and nerves to run through

what are compact bones made out of?

osteons

osteon

the basic structural unit; long cylinders that act as tiny weight-bearing pillars in the bone.

what are osteons made out of?

lamella

lamella

hollow tubes, filled with tiny salts and collagen fibers that allow the bone to resist torsion stress

haversian canal (central canal)

runs through the middle of each osteon and contains small blood vessels for nourishment and nerve fibers for signaling.

structure of spongy bone

Less organized than compact bone, no osteons, have trabeculae

trabeculae

tiny bone struts that are key for helping the bone to resist stress; also where bone marrow is

red bone marrow

makes blood cells

yellow bone marrow

stores energy in the form of fat

osteocytes

maintain healthy bone structure, housed in the lacunae = gaps between the lamellae

osteoclasts

critical in the regeneration of bone through bone remodeling by absorbing bone tissue wherever it is not needed or is degenerating

osteoblasts

build and construct bones by calcifying bone as it forms

ossification (osteogenesis)

the process of bone tissue formation

what are the two types of ossification

intramembranous and endochondral

intramembranous

bone develops from a fibrous membrane to membranous bone; Ex. Clavicle and skull bones

endochondral ossification

bone develops by replacing cartilage to endochondral bone; Ex. all other bones

first step of bone remodeling process

Osteocytes release chemical signals to tell osteoclasts to go to the damage.

second step of bone remodeling process

Osteoclasts release enzymes there that allow them to digest the calcium phosphate, putting the calcium and phosphate back into the blood = resorption

third step of bone modeling process

macrophages promote bone tissue remodeling

fourth step of bone remodeling process

osteoblasts come in and build new bone before they undergo apoptosis

fracture

break

how to treat

reduction (realignment of the broken bone ends) and immobilization (keeping bone stable so it has time to heal itself)

first step of bone repair process

hematoma forms due to hemorrhaged blood clots (from where blood vessels in the bone were torn during the break)

second step of bone repair process

fibrocartilaginous callus forms that spans the break and connects the broken ends

third step of bone repair process

osteoblasts begin forming spongy bone and replacing the cartilaginous callus

fourth step of bone repair process

bone remodeling occurs