B5a: Skeletons Flashcards Preview

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Flashcards in B5a: Skeletons Deck (17):

What are the advantages of an internal skeleton compared to an external skeleton(4)

provides internal framework for the body

grows with the rest of the body

flexible as it contains many joints

allows easy attachment of muscles


Describe cartilage and bones(3)

both are living tissues containing living cells
-therefore are susceptible to infection by bacteria and viruses
-are able to grow and repair themselves


Describe the structure of a long bone(2)

at each end there is a head covered with cartilage

consists of a long shaft containing bone marrow with blood vessels


Why are long bones that are hollow advantageous

Stronger and lighter than solid bones


Describe the development of the skeleton(3)

skeleton starts off as cartilage

cartilage is slowly replaced by the addition of calcium and phosphorus (ossification)

whether a person is still growing can be determined by the amount of cartilage present
(-if some cartilage remains between the head and shaft, the bone and the person is still growing)


Bones are _ but can still be broken by _

very strong, sharp knock


Why are elderly people more prone to fractures

The bones of elderlies lack calcium and phosphorus, which can result in osteoporosis, making them prone to fractures


Why can it be dangerous to move a person with a suspected fracture

Broken vertebrae in the backbone can damage the spinal chord, resulting in paralysis or death


Describe the structure of synovial joints

Contains synovial fluid, a synovial membrane, ligaments and cartilage


Describe the movement of a hinge joint

restricted to only an up and down movement


Describe the movement of a ball and socket joint

has a wider range of movement than a hinge joint - can rotate


Describe the function of synovial fluid

acts as a cushion against shock and a lubricant for easy movement


Describe the function of a synovial membrane

holds in the synovial fluid


Describe the function of cartilage

protects the bone head


Describe the function of ligaments

hold the bones in place


Describe how the biceps and triceps muscles operate(3)

they are antagonistic muscles which work together to bend or straighten the arm
-to raise the forearm, biceps contracts and triceps relaxes
-to lower the forearm, biceps relaxes and triceps contracts


How is arm bending and straightening an example of a liver

elbow acts as a pivot(fulcrum)