Page 14 - 新思维科学学生用书4 样章
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1.2 Why we need a skeleton
can move because there are muscles joined to bones of the skeleton.
Muscles are parts of the body that help us to move.
Questions
1 How does the skeleton protect the brain?
2 Which organs does the rib cage protect?
3 Why do we need strong bones?
4 Explain how our skeleton helps us to move.
Skeletons help us grow
We grow and get bigger because our skeleton
grows. An adult’s skeleton is much bigger than a child’s skeleton. An
adult’s skeleton has stopped growing.
Think like a scientist
Measuring bone lengths
Work with a partner. You will need: a tape measure
Use the tape measure to measure the length, from end to end, of each
other’s:
• upper arm bone • upper leg bone • lower leg bone.
Record the measurements in a table like the one shown here.
Length in cm
Bone
Me Partner
Upper arm bone
Lower arm bone
Lower leg bone
1 Whose bones are longer?
2 Predict what you think the length of a
teenager’s bones would be. Say why.
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