A personalized and smart learning plan
Take a test on your terms and definitions
Scientifically backed study method
See how quickly you can match all your cards
Study terms and definitions
Name the parts of the skeletal system
Looks like no one added any tags here yet for you.
View all (179)
New cards (179)
bones, joints, cartilages, ligaments, tendons
What are the 2 divisions of the skeletal system?
axial and appendicular
What are the 5 functions of the skeletal system?
Mineral and Triglyceride Storage
Blood Cell Production
Matrix always contains _____, _____, ____, _____, ____.
Collagen, ground substance, organic molecules, water, and minerals
T/F: proteoglycans make up a large amount of ground substance
Proteoglycans attract _______.
Proteoglycans help tissue _____________.
Muscle to bone
Bone to bone
Pad/cushion areas around bone
Cells embedded with cartilage are called _____.
What is an osteoblast?
Formation of bone matrix; repair/remodel of bone tissue; produce collagen and proteoglycans (ossification)
What is an osteocyte?
Mature cells that maintain bone matrix
What is an osteoclast?
Cells that break down matrix; bone cells release minerals through osteolysis
Most minerals are in a form of _________.
T/F: mineral component gives weight-bearing strength and is responsible for 3/4 of the weight of the 206 bones in an adult.
False- it's responsible for 2/3 of the weight
Osteocytes are located in spaces called ______, in the _________.
Lacunae; lamellar matrix
Small channels that run through the matrix to transport nutrients and remove waste
Compact bone is made of a repeating functional unit called_____.
Osteon is made up of concentric circles of ________.
Lamella w/ embedded lacunae; and surrounds the central canal
What are perforating canals?
They allow for blood vessels in the central canals to linked to other vessels
Spongy bone is located @ the ______ of ______ & at the center of other bones.
Epiphysis; long bones
Spongy bone contains _____ interconnecting rods and spaces that contain ______.
Trabiculae; bone marrow
T/F: spongy bone has no osteons
Spongy bone is found in locations w/ ______ arriving from many different directions.
______ bone is much lighter than ______ bone and reduces weight of skeleton and makes it easier for muscles to move.
What are the 4 general shapes of bones?
Long, short, irregular, flat
What is an example of a long bone?
What is an example of a short bone?
carpals and tarsals
What is an example of a flat bone?
Sternum, cranial bones
What is an example of an irregular bone?
Vertebrae, hip bones, facial bones
Which bone shape has compact bone on the inside w/ hollow central marrow cavity?
The epiphysis are wider portions at each end, made up of _____.
What is an epiphyseal plate?
Site of growth between diaphysis & epiphysis; solidifies into epiphyseal line when full adult height is reached
What is a medullary cavity?
Center of diaphysis; holds red/yellow marrow
What is periosteum?
Membrane around bone's outer surface; contains blood vessels/nerves; tendons/ligaments attach here
What is endosperm?
Membrane that lines the medullary cavity; contains osteoblasts & osteoclasts; involved in growth & repair
Ossification is _______.
Formation of bone by osteoblasts
Intramembranous ossification is_______.
Bone formation occurs within connective tissue membranes
Endochondral ossification is________.
Bone formation that occurs inside hyaline cartilage
Both intramembranous and endochondral bone formation result in ______ and _____ bone.
Intramembranous ossification occurs primarily in the ______ when osteoblasts begin to produce bone within connective tissue, known as mesenchyme.
In intramembranous ossification, osteoblasts line up ________, & begin depositing bone matrix to form trabiculae, which radiate out from centers of the ossification centers.
On the surface
____ or more _________ exist in each flat skull bone and mature skull bones result from fusion of these centers as they enlarge.
2, ossification centers
Intramembranous ossification generally occurs during the ________ of fetal development, & forms the bones of the skull, mandible, and the clavicle.
First 2 months
Endochondral ossification is initially formed is a ________, which is bone formation in the diaphysis of a long bone.
Primary ossification center
__________ is bone formation in the epiphysis.
Secondary ossification center
What are the steps in endochondral ossification?
Chondroblasts build a cartilage model, then become chondrocytes
Cartilage model hardens (calcifies)
Osteoblasts invade calcified cartilage and a primary ossification center forms the diaphysis
Secondary ossification centers form the epiphysis
Original cartilage model is almost completely ossified; remaining cartilage is known as articular cartilage
During bone growth, when cartilage is broken down, the enclosed cartilage is digested away which opens up a _______.
Bone replaces _____ through the action of _____.
Dying chondrocytes are replaced by ______.
Bones grow in width by the periosteum & the existing matrix _______.
What are the requirements for bone growth?
Mineral supply, vitamin D3, hormones, & vitamins A, B, C, D, K
T/F: timing of epiphyseal closure varies from bone-bone and from person-person
Bones are remodeled in response to what 2 factors?
Free calcium levels in the blood
Pull of gravity & muscles on the skeleton
Bone remodeling involves:
-removal of existing bones by osteoclasts
-deposition of new bones by osteoblasts
In young adults ____ of the skeletal mass is replaced each year.
T/F: spongy bone is replaced more often than compact
In adults, osteocytes in lacunae continuously _____ & _____ surrounding calcium salts.
Remodeling bone (esp. spongy bone) is based on:
Appropriate stress & exercise
T/F: muscle is a major storage site for calcium
False- bone is major storage site
Calcium homeostasis is maintained by _____ & ______.
Parathyroid hormone, calcitonin
Parathyroid hormone (increase or decrease) formation/activation of osteoclasts.
A closed fracture is
Simple; completely internal and only seen on x-rays
An open fracture is
Compound; project through the skin and are at most risk for infection
What are the steps in bone repair?
Broken bone causes bleeding and a fracture hematoma forms
Cells of periosteum/endosteum divide to form a callus(internal/external)
Cartilage model forms first, then osteoblasts enter the callus and form spongy bone; continues for 4-6 weeks after injury
Cancellous bone is slowly remodeled to form compact & cancellous bone
When placed under stress, tissue becomes stronger through ________ & production of collagen fibers.
Increased decomposition of mineral salts
Without mechanical stress, bone does not remodel normally because ________.
Resorption out-spaces bone formation
When there's an absence of mechanical stress, bone weakens through decreased # of ______ and demineralization (loss of bone minerals).
What is osteopenia?
Inadequate ossification that naturally occurs in aging as early as 30-40 years old
What is osteoporosis?
Loss of bone mass that impairs normal function and can lead to more fractures
T/F: osteoporosis is more severe that osteopenia
Osteoporosis is more common in what gender?
For women, osteoporosis usually accelerates after _____ due to decline in circulating estrogen.
A large hole/opening
Smooth, round ended
Lump of bone