Observe a cross-section of spongy bone. Draw and label the following structures as they appear using the 10X objective, or by viewing an image from the internet. Label the bone marrow and the bony trabeculae.
A network of irregularly shaped sheets of bone (trabeculae). The trabeculae are only a few cell layers thick. The spaces between the trabeculae contain the bone marrow.
Conclusion Questions Matt was playing football when he was tacked, knocked to the ground, and piled upon, knocking him unconscious. What properties of bone prevented Matt from breaks and damage to internal organs?
Bones are hard so that they form a sturdy protection around internal organs. When the body is hit or under pressure the bones absorb the shock or break instead of the internal organs that would be more severely damaged.
What role did Matt being knocked unconscious play in his body’s ability to resist damage? (Ie, why might being knocked unconscious be beneficial in this case?)
When unconscious the muscles relax and are not tense. If Matt was unconscious before falling his relaxed muscles would allow him to fall more gently and not hit the ground so hard. Also, being unconscious reduces the panic and anxiety that go along with getting injured, calming the body systems and allowing them to rest and heal.
What type of fibers or minerals do you find in the extracellular matrix of bone? How does this composition relate to the properties of bone?
Calcium makes them strong.
What aspects of bone’s structure make it stronger than concrete? Think about the engineering design of bone. Use the terms tensile strength and compressional strength in your answer.
Bone structure is somewhat similar to reinforced concrete that contains structural metal reinforcement rods or bars. These metal reinforcements are commonly called rebar. Protein strands make up the rebar of bone. Calcium and phosphorus mineral crystals deposited around the protein strands are somewhat like the concrete poured around the rebar in reinforced concrete. The protein strands provide the tensile strength that holds everything together and the minerals provide the solid structure. If bones were made only of protein, they would be too flexible. If bones were made solely from minerals, the skeleton would be too brittle. How do red bone marrow and yellow bone marrow differ in function?
Red bone marrow makes red blood cells, platelets and most white blood cells. Yellow bone marrow makes some white blood cells but is mostly adipose tissue (fat.)
Explain how the structure of spongy bone helps reduce the overall weight of bone.