Pre-Lab: Comparing Bird and Mammal Bones
Problem Is the density of an animal's bones related to the way the animal moves?
Materials cross-sections of chicken, duck, and cow bones; hand lens; small chicken, duck, and cow bones; balance
Lab Manual Chapter 28 Lab
Skills Focus Form a Hypothesis, Design an Experiment, Measure
Connect to the In order to move, an animal must generate physical force and apply this force against the air, the water, or the ground. The force is generated by the contraction of muscles. In vertebrates, the muscles are attached to bones. The joints that connect bones bend or straighten when groups of muscles contract. There is a close link between the structure of an animal's skeletal and muscular systems and how the animal moves. In this lab, you will investigate whether there is a similar link between the density of bones and how an animal moves.
Review What type of skeleton do vertebrates have? List one advantage of this type of skeleton.
Explain Why are pairs of muscles or two different groups of muscles needed to bend and straighten a joint?
Apply Concepts Why do you think humans have only 4 bones in each arm and shoulder, but 27 bones in each wrist and hand? Hint: Compare the movement of your arm and your hand when you button a shirt?
Preview the procedure in the lab manual.
Compare and Contrast Compare the type of data you will collect in Part A to the type of data you will collect in Part B.
Predict How might looking at cross-sections of bones help you form a hypothesis about the relative density of the bones?
Design an Experiment Will you need to use samples with the same mass in Part B? Why or why not?
Visit Chapter 28 online to test yourself on chapter content and to find activities to help you learn.
Untamed Science Video Join the Untamed Science crew as they interview experts to learn more about how the sex of offspring is determined in some animals.
Art in Motion Watch an animation that shows the motion of joints in both exoskeletons and endoskeletons.
Art Review Review your understanding of vertebrate brains.
InterActive Art Look at the structure and function of the water vascular system in a sea star.
Data Analysis Investigate some of the ways mammals survive in cold temperatures.