Anatomy Exam 2 (02/22/24 update)
Canaliculi Transfer
-Mineralized matrix- NO diffusion through the matrix. -Protoplasmic (arm) extension of adjacent cells connect within Canaliculi. -Waste, nutrients, gases etc. diffuse from cell to cell.
At what age do our bones stop growing in length?
15-20
At what age do our bones stop growing in width?
15-20, but will continue to form new bone for life
When does the growth of cartilage end?
18-20 years
How many types of osseous tissue does every bone have?
2
What percent of cartilage is water?
60-80%
What percent of calcium is held in the bone?
98%
What percent of the body's calcium is found in bones?
98%
Rickets Syndrome
A lack of vitamin D or calcium can cause a child to have frail bones or an unstable figure
Does cartilage heal in adulthood?
A little bit :)
What is bone? LMAO
A supporting connective tissue that has specialized cells within a matrix
What is an example of adipose CT?
Adipocytes
Where does interstitial growth occur?
Along epiphyseal (growth) plates
Where does bone develop in intramembranous ossification?
Between layers of fibrous membrane
What is an example of fluid CT in bone?
Blood
What is an example of fluid connective tissue in the skeleton?
Blood
What does every bone have?
Blood vessels, nerves, & lymphatic vessels
What is osseous tissue?
Bone
What happens in appositional growth? (specific)
Bone cells lay down new bone tissue along outside of bone (deep to periosteum)
What is ossification?
Bone development
What happens in interstitial growth?
Bone replaces cartilage, where cartilage cells have died
Osteoclasts
Break down old matrix (osteoids) & releases calcium and phosphate
What inorganic compounds are found in bone?
Calcium & Phosphate
What is the skeleton made of?
Calcium/phosphate
What is formed first in endochondral ossification?
Cartilage model (like rubber dog bone)
What is an example of cartilage supporting CT?
Chondroblasts & chondrocytes
What structures are primarily composed of organic compounds?
Collagen fibers
Osteon
Concentric rings of matrix in compact bone
What are the three main connective tissues of the skin?
Connective tissue proper, supporting connective tissue, fluid connective tissue
What types of CT proper are in the skeleton?
Dense regular & adipose
What do inorganic compounds help with?
Durability & hardness
In intramembranous ossification, what is the process to form bone?
Embryonic connective tissue cells change into osteoblasts --> forms bone
What is the membrane on the inside of a bone called?
Endosteum
What structure is trabeculae surrounded by?
Endosteum
Where does some cartilage remain after endochondral ossification?
Epiphyseal (growth) plate
Where is spongy bone found?
Epiphysis & center of bone organ
How often is compact bone replaced?
Every 10 years
How often is spongy bone replaced?
Every 4 years
True or false: collagen does NOT resist tension.
False
What are examples of dense regular CT?
Fibroblasts & fibrocytes
Which bones are formed with intramembranous ossification?
Fontanels (baby's soft spots)
Interstitial growth
Growth of bone in length
Appositional growth
Growth of bone in width
What does spongy (cancellous) bone look like?
Honeycomb-like network
Which cartilage type is the most abundant?
Hyaline cartilage
Osteoblast
Immature bone cells that secrete new matrix (osteoid)
Where is fibrocartilage located?
Intervertebral discs, menisci
What are the two types of ossification?
Intramembranous and endochondral
Which type of ossification forms mainly flat bones of skull + the patella?
Intramembranous ossification
Why does the perichondrium act as a water balloon in cartilage?
It helps with cushioning movement
Where is cartilage found in the body?
Joint discs, intervertebral discs, symphysis pubis
Which structures in bones are made up of dense regular CT proper?
Ligaments, bone sheaths, tendons
Which bones are formed by endochondral ossification?
Mainly long bones of body, especially appendages
Osteocyte
Mature bone cells that are trapped in lacunae
What general type of tissue do all connective tissues start as?
Mesenchyme
Does fibrocartilage have perichondrium?
No
Where is hyaline cartilage located?
On end of bone growth plate, coastal cartilage
What type of compounds are osteoids made up of?
Organic & inorganic
What are osteoids made up of?
Organic & inorganic compounds
What does compact bone look like?
Organized "nested rings" in periphery of bone
What is an example of bone supporting CT?
Osteoblasts & osteocytes
What is another name for the non-cellular matrix of a bone?
Osteoid
What cells/structures are found in compact bone? (2)
Osteon & lacunae
What is cartilage surrounded by?
Perichondrium
What do organic compounds do?
Provide flexibility
What are spongy bone cavities filled with?
Red bone marrow
Where is blood formed?
Red bone marrow
Where are blood cells produced?
Red bone marrow in cavities of spongy bone
What does the water in cartilage help with?
Resisting compression
What is fibrocartilage good at?
Resisting twisting and compression
What is the most common type of injury seen in cartilage?
Shearing forces in injury (cartilage cannot sustain it)
What is osseous tissue made up of?
Spongy bone & compact bone
What happens down the lateral diaphysis of a compact bone?
Tension
Lacunae
The cavities that bone cells are trapped within in compact bone
Why does the spongy bone form trabeculae (beams)?
To help resist directional stresses
What is elastic cartilage good at?
Tolerating repeated bending & recoil
What do beams of compact bones help with?
Transmitting weight within the bone
True or false: bone replaced cartilage over time
True
True or false: chondrocytes have adapted to the low oxygen in cartilage
True
True or false: spongy bone and compact bone have the same matrix and bone cells
True
What forces do organic compounds resist?
Twisting & tension
When can bone change from spongy bone to compact bone and back again?
When there are different body signals
Osteoprogenitor Cells
Will form all new bone cells, can divide
Where is elastic cartilage located?
Within ears & epiglottis
Where is adipose tissue stored?
Yellow bone marrow
What type of bone marrow is used for energy storage?
Yellow marrow
Does cartilage have blood vessels/nerves?
Yes
Does hyaline cartilage have fibers?
Yes, but they are too little to see
Does elastic cartilage have fibers?
Yes, many
Are there blood vessels in the perichondrium?
Yes- they help with growth & repair as well as provide gas + nutrients to cartilage cells
short bones
carpals and tarsals
What happens down the medial diaphysis of a compact bone?
compression
pneumatized bones
face bones
Chondroblasts
immature cartilage cells
Chondrocytes
mature cartilage cells, dividing cells trapped in lacunae
sesamoid bones
patella
flat bones
scapula, sternum, skull
Functions of the skeleton
support soft tissues of body, mineral reservoir, energy storage, blood cell production, protection of vital organs, leverage & movement
sutural (wormian) bones
sutures (skull)
long bones
tibia, fibula, phalanges, metacarpals, etc