Musculoskeletal System Flashcards
what are the three basic skeletons found in organisms
- hydrostatic skeleton
- exoskeleton
- endoskeleton
what is the function of the hydrostatic skeleton and an example
a volume of fluid enclosed within body of an organism that acts as a skeleton
- provides support and shape to organsim
eg. in amoeba
what is the function of the exoskeleton and an example
hard external covering that protects and supports the organism eg. in insects and molluscs
what is the function of the endoskeleton and an example
internal skeleton that supports the organism from the inside eg. in trees and vertebrates
the musculoskeletal system is comprised of the (…) and (…) systems of the body. the systems are independent but they work together to perform many functions
the musculoskeletal system is comprised of the skeletal and muscular systems of the body. the systems are independent but they work together to perform many functions
the skeletal system comprises the (…) and (…) of the organism
the skeletal system comprises the bones and cartilage of the organism
what are the functions of the skeletal system
- attachment
- framework
- haematopoiesis (RBC development from bones with red bone marrow)
- mineral homeostasis (strength and mineral balance)
- movement
- protection
- lipid storage (yellow bone marrow)
what is bone made of?
1/4 water
1/4 bone cells (osteoid) - organic
1.2 calcium phosphate- inorganic
what are the two types of bone? and an example
- long bones- have shaft eg. tibia
2. short/irregular/flat/sesamoid bones- no shaft eg. sternum
outline the structure of a long bone
- shaft/diaphysis contains compact bone with a marrow cavity containing yellow bone marrow
- 2 ends/epiphyses have an outer covering of compact bone with cancellous bone inside
- metaphases area: in mature bones, area between diaphyses and epiphyses vs in a growing bone, epiphyseal cartilage/plate separates diaphysis from epiphyses (ossifies at end of growth)
how does a long bone thicken?
- new bone tissue is deposited under the periosteum (vascular connective tissue membrane covering bone) which has osteoclasts and osteoblasts
- hyaline cartilage covers the epiphysis where bone forms joint with other bone
outline the structure of short/irregular/flat and sesamoid bones
- thin outer layer of compact bone
- inside contains cancellous bone which contains red bone marrow
- except cranial bones(has non adherent dura matter), the rest are covered by periosteum
what are the four types of cells found in bone
- osteogenic (undifferentiated stem cells)
- osteoblasts (bone forming or bone building cells)
- osteocytes (cells formed by the trapping of osteoblasts in a developing bone matrix)
- osteoclasts (cells responsible for the reabsorption of bone to achieve or maintain optimal shape
what would bone tissue contain
- bone cells
- compact bone and Haversian system
- cancellous bone
- blood vessels
- nerve supply
what is compact/cortical bone
bone with very few spaces between its compartments and can look solid to the naked eye
- many Haversian systems/osteons found in compact bone
what is the function of cortical bone
form the external layer of all bone and is the main component of diaphyses of long bones
- provide protection, support, resistance to stress by weight and movement
what is the Haversian system composed of
- central Haversian canal contains lymph, nerve and blood vessels which are surrounded by calcified plates of bone (lamellae)
- between lamellae are lacunae (tiny spaces) containing osteocytes and extracellular fluid
- canaliculi connect lacuna to each other and to central Haversian canal
where is cancellous bone found
where there is little stress or where stress comes from many directions (light, so moves easily by muscle)
2. ribs, backbone, breastbone, hips, ends of longbows
what is the structure of cancellous bone
- not contain Haversian canals, looks like honeycomb
- contains trabecular of few lamellae (calcified plates of bone) and osteocytes interconnected by canaliculi
- spaces between trabeculae contain red bone marrow that produces blood cells
what is the function of cancellous bone
protects and supports the red bone marrow
