A&P - Bone Tissue
Intramembranous, endochondrial
Two types of ossification.
Trabeculae
What does spongy bone contain instead of osteons?
Triglycerides
Yellow marrow stores this form of energy storage.
chondroblasts
mesenchymal cells form a model of _____________ or cartilage matrix
Linear
Compact bones have this kind of strength.
Vitamin C
... deficiency can cause scurvy or loss of bone mass and strength.
decreased protein synthesis
2nd effect of aging on skeletal system, results in decreased production of matrix components and making bones more susceptible to fracture (more brittle).
osteoporosis (loss of bone mass)
Aging effect: loss of calcium and other minerals from the bone matrix, which may result in ...
ossification
An ______________ forms from mesenchymal cells as they convert to osteoblasts and lay down osteoid matrix.
Fracture
Any break in a bone.
mesoderm, ectoderm
Around the 5th week of embryonic life, extremities develop from limb buds, which consist of .... and ....
Hematopoiesis
Blood cell formation, occurs in red marrow of bones.
appositional
Bone can grow in thickness or diameter only by ... growth matrix deposition.
7th
Bone formation begins when the mesenchymal cells provide the template for subsequent ossification, which usually occurs in the ____ week of life.
Osteogenesis (or ossification)
Bone formation is called ...
intramembranous, endochondrial
Bone forms from mesoderm by __________________ or _________________ ossification.
Appositional
Bone grows in diameter as a result of _________________ addition.
25, 25, 50
Bone matrix is: ___% H2O ___% Protein ___% Mineral salts
Blood
Bone releases or absorbs Ca++ depending on _______ Ca++ levels.
osteoblasts
Bone-building cells, deposition, secrete collagen, and other organic components, build matrix
Support
Bones ___________ the soft tissues and provide attachment sites for muscles.
movement
Bones assist skeletal muscles to produce ___________.
hand and foot plates (which become hands and feet)
By the 6th week, a constriction around the middle portion of the limb buds produces ...
Osteons (or Haversian systems)
Compact bone is arranged in units called ...
80
Compact bone makes up ___% of the bone in our bodies.
Epiphyseal artery
Continues into the medullae to supply blood for the marrow and osteocells.
minerals, vitamins D, C, K, B12, calcitriol, hormones
Factors that affect bone growth.
Resting cartilage, proliferation cartilage, hypertrophic cartilage, calcified cartilage
Four zones of the epiphyseal plate.
support, protection, movement, storage and release of minerals, hematopoiesis, energy storage
Functions of the skeletal system
when the ephiphyseal plate closes and is replaced by bone (no more epiphyseal line)
How do we know when the bone has completed its growth in length?
6-8hrs to weeks
How long the fracture hematoma lasts for.
Every 2-4 months
How often bone remodeling occurs.
insulin-like growth factors (IGFs)
Important hormones for stimulating growth during childhood are the ....
Protected
Many of the body's internal organs are _________ by bony coverings.
osteoblasts
New bone is constructed by __________, a process called "deposition:
osteoclasts
Old bone is constantly destroyed by _________, called "resporption"
Bone remodeling
Ongoing replacement of old bone tissue by new bone tissue.
Osteoclasts
Osteo(clasts/blasts) break down bone tissue.
Osteoblasts
Osteo(clasts/blasts) build bone tissue.
Same
Osteons are aligned in the ________ (same/different) direction along lines of stress.
blood vessels, lymphatic vessels, nerves, and osteocytes
Osteons contain ...
thyroxine, insulin, estrogen, testosterone, calcitonin, parathyroid hormone
Other hormones that stimulate bone growth
Periosteal arteries
Pass through Volkmans' canals to a multitude of vessels that supply the outer compact bone region.
Spongy
Pelvis, vertebrae, skull, ribs, and the ends of long bones are example of this type of bone.
Hematopoiesis
Red marrow is the site of this function.
True
True or false: the process of calcification occurs only in the presence of collagen fibers.
Bone remodeling (the final step)
Resorption of bony callus and fracture fragments, compact bone replaces spongy bones
3-4 months
Soft callus turns into bony callus
Hematopoiesis
Spongy bone is also the site of ...
20
Spongy bone makes up ___% of the bone in our bodies.
Vitamin A
Stimulates osteoblastic activity
Epiphyseal artery
Supplies marrow and osteocells with blood.
Nutrient artery
Supplies osteocytes with blood.
Periosteal arteries
Supplies outer compact bone region with blood.
notochord
The --- is a flexible rod of tissue that lies in a position where the future vertebral column will develop.
epiphyseal plate
The activity of the ... is the only means by which the diaphysis can increase in length.
Intramembranous
The flat bones of the skull, mandible, clavicle are the result of this type of ossification.
Protect the red bone marrow
The main function of spongy bone.
calcium phosphate, calcium carbonate
The main inorganic salts found in the matrix of bone tissue.
compact, spongy
The periosteum first forms a collar of spongy bone, that is then replaced by _________ bone, while the __________ bone stays in the center.
calcification (or mineralization)
The process of depositing salts in a framework of collagen fibers.
Ca++ and phosphorus
The two main minerals stored and released by bones.
True
True or false: a lot of repetitive stress can lead to a changed shape along the lines of mechanical stress.
True
True or false: basement membrane is only on the epiphyseal side.
False (it is highly vascular)
True or false: bone has a low blood supply.
True (bone, cartilage, dense connective tissue, epithelium, blood forming tissues, adipose tissue, nervous tissue)
True or false: bone is made up of several types of tissues.
True
True or false: each individual bone is an organ.
False (osteoclasts do)
True or false: osteoblasts have multiple nuclei.
False (osteoblasts do)
True or false: osteoclasts have one cell, one nucleus.
True
True or false: spongy bone does not contain osteons.
Compact bone
Very hard and dense bone is called ...
V12 K
Vitamins ... and ... deal with the synthesis of proteins in normal bone.
human growth hormone (hGH)
What IGFs are stimulated by.
inflammatory response, swelling
What accompanies the fracture hematoma
homeostatic control of calcium and phophate
What calcitonin and parathyroid hormone aid in.
The bone has completed its growth in length
What do we know has happened when the epiphyseal line disappears?
Pro callus (fibrocartilaginous callus or "soft callus")
What forms 3 weeks after a fracture
bony callus (or "hard callus")
What forms 3-4 months after a fracture
Collagen fibers
What gives the matrix of bone some flexibility.
pituitary gland
What hGH is produced by
Spongy
What kind of bone is found in areas of less stress?
At birth
When do we develop secondary ossification centers?
En Utero
When do we develop the primary ossification center?
Yellow marrow
Where energy is stored in adult bones.
Endosteum, periosteum
Where osteoblasts are found
cardiac and muscle contraction, nerve conduction, enzyme function, blood clotting
Why Ca++ is important
To renew bone tissue before it deteriorates and breaks down
Why do we have bone remodeling?
Proliferation cartilage
Zone of the epiphyseal plate: chondrocyes divide and move toward the diaphysis to replace old cells.
hypertrophic cartilage
Zone of the epiphyseal plate: maturation of chondrocytes
Resting cartilage
Zone of the epiphyseal plate: nearest epiphysis, no growth, chondrocytes anchor epiphysis to plate.
calcified cartilage
Zone of the epiphyseal plate: osteoblastic vs. osteoclastic activity
Nerves
_________ follow vessels into bone tissue and the periosteum where they sense damage and transmit pain messages.
thyroid, parathyroid
__________ comes from the thyroid gland _______________________ comes from the parathyroid gland .
spongy
________________ (compact/spongy) bone forms most of the structure of short, flat, and irregular bones, and the ends of long bones.
mineral salts, collagen fibers
________________ (mineral salts/collagen fibers) confer hardness of bone while _____________ (mineral salts/collagen fibers) give bone its great tensile strength.
periosteum
a connective tissue covering of the surface of the bone which contains osteogenic cells, protects bone, assists in fracture repair, helps nourish bone tissue, and serves as an attachment point for ligaments and tendons.
epiphyseal and metaphyseal veins
accompany epiphyseal and metaphyseal arteries in the epiphysis
hyaline cartilage
at the ends of the bones to reduce friction and absorb shock at freely moveable joints
Vitamin A
calcitriol synthesis is dependent on the availability of ...
interstitial growth
cartilage/bone that grows from within itself, causes bones to lengthen
Osteoclasts
derived from white blood cells, secrete acids and enzymes and serve to BREAK DOWN bone tissue, destroy matrix, osteolysis, resporption.
periosteal veins
exit with their periosteal arteries in the periosteum
Fracture hematoma
formation of a blood clot or blood tumor from broken blood vessels.
appositional growth
growth at the outer surface of a bone during endochondral ossification, resulting in an increase in the bone's thickness
negative
homeostasis of calcium and phosphate are controlled by a ___________(positive/negative) feedback system.
Calcitriol
hormone from kidneys that promotes calcium and phosphate ion absorption along the digestive tract.
epiphyseal plate
in growing bones
Osteocytes
mature bone cells and the principal cells of bone tissue, live in the matrix.
pro callus (which then is transformed into a soft callus)
organization of the fracture hematoma into granulation tissue, called a ....
Nutrient artery
passes through the nutrient canal and sends branches into the central Haversian canals to provide for osteocytes.
Periosteal bud
primary ossification center, vascularization, cartilage matrix replaced with bony matrix and osteocytes
osteogenic cells
process of ossification: _________________ --> osteoblast --> lay down organic matrix --> becomes osteocyte once matrix formed
endochondrial ossification
replacement of cartilage by bone
metaphyses
the areas between the epiphysis and diaphysis
epiphyses
the ends of the bone
intramembranous ossification
the formation of bone directly from or within fibrous connective tissue membranes.
endochondrial ossification
the formation of bone from hyaline cartilage models (most bones of the body)
endosteum
the lining of the marrow cavity, contains osteogenic cells
diaphysis
the shaft of the long bone
marrow cavity
the space within the diaphysis, fatty yellow bone marrow
osteogenic
these types of cells undergo cell division and develop into osteoblasts
nutrient veins
vein: follow the nutrient artery in the diaphysis
