Rock Cycle - Past Life (4)
Post Lab 

  • Recognizing bones.
  • Comparing chicken and cow bones.
  • bone
  • cross section
  • preserved
  • chicken bone and steak bone
  • Swift-GH microscopes

Students compare chicken and cow bones.

A fossilized dinosaur bone


The bones of different animals are very unique and can be distinguished easily. For example, a larger animal has proportionately larger bones than a small animal. The larger the animal, the greater the bone diameter needed to support the weight of the animal. Larger bones usually correspond to a lack of agility; a mouse is much quicker in its movements than is an elephant.

Students sometimes do not realize that bones are living parts of organisms. For example, the interior of a bone is porous. Some of these openings host blood vessels.

  1. Ask the students to bring a chicken bone and a steak bone to school. Make sure the bones have been cleaned.
  2. Instruct the students to carefully draw the bones. Make sure they look at cross-sections, not just the surfaces. They should discover that both types of bones have something in common - a porous interior. After they have discovered this, explain that the holes hosted blood vessels that nourished the bones when they were part of a living organism.
  3. Ask the students to list differences between the bones. They should note that the steak bone is more dense than the chicken bone; use this to lead a discussion about how the two organisms live. Bird bones tend to be light and hollow, because birds are small, and because they need lightweight bones to be able to fly.

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