Bones Flashcards
What is osseous tissue?
another word for bone
What is part of the skeletal system?
bones, cartilages, ligaments
What is cartilage?
dense connective tissue made to reduce friction where bones articulate
What are ligaments
tough fibrous connective tissue that connect bones to other bones where joints are located
Functions of the skeleton
-support
-protection- skull, rib cage
-movement
-blood cell- red marrow
production
-mineral storage
homeostatis (normal calcium and phosphorus)
Name the parts the bone
-supporting connective tissue
-specialized cells
-solid matrix (bone itself)
-bone linings (line the bone)
periosteum (outer)
endosteum (inner)
What is osteogenic connective tissue? Can bone be added here?
periosteum and endosteum (bone can be added here)
What is fascia?
type of connective tissue that is an muscle attachment site and its part of the presidium
How thick is the endosteum?
one cell thick
What does the endosteum line?
the medullary cavity
What makes bone hard?
the mineral component does. aka the calcium phosphate (calcium phosphate becomes hydroxyapatite crystals)
What makes bone flexible?
collagen fibers (so that bone is not brittle)
What are osteocyte?
live inside the bone matrix, provide nutrients and keep bone tissue alive
What are osteoBlast?
bone building, secrete osteoid, one nucleus
what minerals do we need to build bone?
calcium and phosphorus
What do osteoblast become?
Osteoblast become osteocyte’s
What are osteoclast?
multiple nuclei, involved in bone removal
How is bone replacement called?
bone remodeling
What is bone remodeling?
COORDINATED removal and replacement of bone tissue by osteoclasts and osteoblast
When do we need to go through bone remodeling?
when we are
changing bone shape (exercise)
replacing old/damaged bone (over time)
releasing mineral stores
What are the steps of bone remodeling?
Resting phase –> RESORPTION osteoclast eats bone –> reversal –> DEPOSITION (osteoblasts) –> some of the osteoblasts get stuck become mineralize
What is resorption?
Osteoclast eating away at bone
What is deposition?
building bone by osteoblasts
What do you need to go through bone remodeling?
essential nutrients, vitamins, hormones
What hormone is involved with osteoclasts?
parathyroid
What hormone is involved with osteoblast?
calcitonin
Calcium level drops what do we do?
- Parathyroid release parathyroid hormone
- Bones release calcium via osteoclasts that eat the bone and release the calcium
- kidneys will retain more calcium
- intestine will absorb more calcium from food
Calcium levels are too high what do we do?
- Thyroid releases calcitonin
- Osteoblasts make bone
- Kidneys retain less calcium aka less uptake and release more of it in the urine
What are the two types of bone?
Compact bone (cortical bone) (denser less spaces) Spongy bone (cacellous, tradecular bone) (lots of spaces)
How is bone different?
Bone is made of the same things just organized differently
What is the basic functional unit of bone?
osteon (long tubes of bones)
What is compact bone out of?
osteon
What are osteons made out of?
lamellae, osteons have a central canal to get nutrients,
What is trabeculae?
makes spongy bone lightweight, tabeculae are branching plates
Where is spongy bone found? where is compact bone fund?
Cortical bone is on the outside, spongy bone is on the inside
Where is bone marrow located?
located in the spaces of the spongy bone
Long bones have two ends. What is that called?
epiphysis (spongy bone)
What is the body or shaft of the bone called?
diaphysis (cortical bone)
What is metaphysics?
wide part of the diaphysis, where we add bone
What is the Epiphyseal plate?
Line separating the diaphysis and epiphysis, made of cartilage
What do you have on the surface of the epiphysis?
articular cartilage to decrease friction
What is ossification/osteogenesis?
replacing the hyaline cartilage with bone (fetus)
When calcium is deposited into the bone what is that called?
ossification (2 types) intramembranous ossification or endochrondral ossification (limb development)
What is Step 1 of bone development?
- chondrocytes increase in size and some die
- cavities form
What is Step 2 of bone development?
- blood vessels bring nutrients
- perichondrium converts to periosteum & into osteoblasts
- osteods form bone collar
What is Step 3 of bone development?
- capillaries and osteoblasts go to the center
- spongy bone starts forming in the center
What is step 4? of bone development?
- increase in size
- diameter enlargement
Step 5 of bone development?
- secondary ossification changes start aka epiphysis changes
- osteoblasts come to allow bone building to happen after
Step 6 of bone development?
- epiphyseal plate forms
- epiphyses fills with spongy bone
- osteoblasts invade shaft and build bone as the cartilage is getting larger too
Step 7 of bone development
-bone matures
-rate of epiphyseal cartilage enlargement decreases
-rate of osteoblasts activity increase
both things cause epiphyseal closure and only a epiphyseal line is left
What is the articular cartilage made of?
remaining from all the cartilage in the epiphysis
What are the 7 bone types?
flat bones- ex occipital bone
short bone- carpals (short bones are almost all spongy bone)
irregular bones- vertebrae
long bones- ex femur don’t forget the clavicle is a long bone (only long bone not in the limbs)
sesamoid bones- found at joints and form inside of TENDONS, reduce friction at a joint
