Sept 24 Lecture: The Skeletal System Flashcards
What are the three main components of the skeletal system
Bones, joints, and supporting tissue
Describe the main functions of the skeletal system
Protection- bones like the skull protect organs like our brains, storage - stores calcium which is important for function in every cell in our body, fat storage in yellow bone marrow, blood cell production in red bone marrow, AIDS in movement, and support
Describe the five bone shapes
Long bones are longer than they are wide, short bones are as long as they are wide, flat bones are broad flat and thin, says in my bones are round flat bones found in tendons, and a regular bones don’t fit into any other category
How many bones are there in the body
206
How much does a skeleton weigh
About 25 lb which is 14% of total body weight
What is the middle shaft of the bone called
Diaphysis
What are the two ends of the bone called
Epiphysis
What is the outer layer on bone and what does it do
It is the periosteum and it’s a membrane made of dense irregular connective tissue in which nerves and blood vessels run through.
What is the center of the bone called
The medullary cavity
What are the two textures of Bones
Compact phone which is the hard dense outer region and spongy bone which is the inner honeycomb like framework of trabeculae
What is the cartilage on the end of a bone
It’s called articular cartilage and it’s a thin layer of highline cartilage
What is the structure of flat bones, irregular bones, and sesamoid Bones
They have no diaphysis, epiphysis, or medullary cavities. The outer layers are made of thin compact bone while the middle layer is spongy bone and bone marrow
What is the inner surface of bone called
The endosteum
Describe red bone marrow
Redbone Mount is made of moose connective tissue and it’s a site of hematopoiesis - the production of red and white blood cells and platelets. The amount of red bone marrow reduces with age.
Where is red bone marrow found in the body
The pelvis, the proximal epiphysis of femur and humorous, the vertebrae, ribs, sternum, scapulate, clavicles, and some bones of the skull.
What is yellow bone marrow
Adipose tissue that has limited storage for triglycerides
Describe this microscopic structure of Bones
Bone is a specialized connective tissue that is mostly ECM. The ECM is a ground substance with protein fibers scattered within. There is an inorganic matrix that makes up 65% of the bones weight, and an organic matrix that makes up 35% of the bones weight
What is the inorganic matrix of bone
Is the ground substance of bone that’s made of calcium and phosphorus salts that exist as a large molecule of hydroxyapatite crystal. It makes bones strong and resistant to squishing.
What is the organic matrix of bone like
The organic matrix called osteoid is made of mostly collagen.
What would happen if you remove the inorganic matrix from a bone
It would bend and become really squishy
What would happen if you remove the organic matrix from the bone
It would be brittle and shatter
What are the three main types of bone cells
Osteoblast which build and deposit bone (formation), osteoclast which carved bone. ( Resorption), and osteocytes which are mature bone cells
What is the difference between ossification and remodeling
Ossification is when bones become bones it is the initial process of development, and remodeling is a lifelong process of replacing the skeleton every 10 years
