Chapter 13 Bones and Muscles Table of Contents Chapter Preview 13.1 Organ Systems and Homeostasis 13.2 The Skeletal System 13.3 The Muscular System 13.4 Machines and the Body
Chapter 13 Bones and Muscles
Table of ContentsChapter Preview
13.1 Organ Systems and Homeostasis
13.2 The Skeletal System
13.3 The Muscular System
13.4 Machines and the Body
Chapter 13 Bones and Muscles
Chapter Preview Questions
1. The position of an object can be changed by
a. pushing on the object.
b. pulling on the object.
c. pushing or pulling on the object.
d. measuring the object’s weight.
Chapter 13 Bones and Muscles
Chapter Preview Questions
1. The position of an object can be changed by
a. pushing on the object.
b. pulling on the object.
c. pushing or pulling on the object.
d. measuring the object’s weight.
Chapter 13 Bones and Muscles
Chapter Preview Questions
2. The magnitude of a force is the same as
a. its strength.
b. its direction.
c. the distance the force moves an object.
d. friction produced by the force.
Chapter 13 Bones and Muscles
Chapter Preview Questions
2. The magnitude of a force is the same as
a. its strength.
b. its direction.
c. the distance the force moves an object.
d. friction produced by the force.
Chapter 13 Bones and Muscles
Chapter Preview Questions
3. The bigger the change in an object’s motion, the
a. smaller the push or pull required.
b. bigger the push or pull required.
c. more likely the object will move in more than
one direction.
d. more likely the object will stop moving.
Chapter 13 Bones and Muscles
Chapter Preview Questions
3. The bigger the change in an object’s motion, the
a. smaller the push or pull required.
b. bigger the push or pull required.
c. more likely the object will move in more than
one direction.
d. more likely the object will stop moving.
Chapter 13 Bones and Muscles
Chapter Preview Questions
4. When you use your foot to stop a rolling ball, you are
a. pulling on the ball.
b. pushing on the ball.
c. changing the direction in which the ball rolls.
d. changing the force that started the ball rolling.
Chapter 13 Bones and Muscles
Chapter Preview Questions
4. When you use your foot to stop a rolling ball, you are
a. pulling on the ball.
b. pushing on the ball.
c. changing the direction in which the ball rolls.
d. changing the force that started the ball rolling.
Chapter 13 Bones and Muscles
A cat sleeps on one end of a seesaw, while a mouse crouches on the other end. The cat wakes up and walks away. How will the forces acting on the ends
change? How will the forces change if the cat runs across the board toward the mouse?
How do the physical principles of forces and machines relate to the functions of your muscles and skeleton?
Chapter 13 Bones and Muscles
Latin Word Origins
Latin Word Meaning of Latin Word Key Term
in- notinvoluntary muscle Type of muscle that is not under a person’s conscious control
Chapter 13 Bones and Muscles
Latin Word Meaning of Latin Word Key Term
ligare to tieligament Connective tissue that holds bones together
Latin Word Origins
Chapter 13 Bones and Muscles
Latin Word Meaning of Latin Word Key Term
porus a tiny opening or hole
osteoporosis A condition in which bones lose minerals, develop larger openings than normal bones, and become weak
Latin Word Origins
Chapter 13 Bones and Muscles
Latin Word Meaning of Latin Word Key Term
resistere to place againstresistance force The force that a lever exerts against an object
Latin Word Origins
Chapter 13 Bones and Muscles
Latin Word Meaning of Latin Word Key Term
voluntas free willvoluntary muscle Type of muscle that is under a person’s conscious control
Latin Word Origins
Chapter 13 Bones and Muscles
Apply It!
1. How does the meaning of the Latin word ligere help you to
understand what a ligament is?
Ligare means to tie and a ligament holds bones together.
2. What two key terms in the table come from the Latin word
voluntas? What does this Latin word mean?
Voluntary muscle and involuntary muscle. It means free will.
Chapter 13 Bones and Muscles
End of Chapter Preview
Chapter 13 Bones and Muscles
Section 1: Organ Systems
and HomeostasisWhat are the levels of organization in the body?What systems are in the human body, and what are their functions?What is homeostasis?
Chapter 13 Bones and Muscles
The Epidermis
In some ways, the skin is the body’s largest organ.
Chapter 13 Bones and Muscles
Organs and Organ Systems
Each organ in your body is part of an organ system, which is a group of organs that work together to perform a major function.
Chapter 13 Bones and Muscles
Cell Specialization
Click the Video button to watch a movieabout cell specialization.
Chapter 13 Bones and Muscles
Links on Body Systems
Click the SciLinks button for links on body systems.
Chapter 13 Bones and Muscles
End of Section: Organ Systems
and Homeostasis
Chapter 13 Bones and Muscles
Section 2: The Skeletal System
What are the functions of the skeleton?What role do joints play in the body?What are the characteristics of bone, and how can you keep your bones strong and healthy?
Chapter 13 Bones and Muscles
What the Skeletal System Does
Your skeleton has five major functions. It provides shape and support, enables you to move, protects your organs, produces blood cells, and stores minerals and other materials until your body needs them.
Chapter 13 Bones and Muscles
Joints of the Skeleton
A joint is a place in the body where two bones come together. Joints allow bones to move in different ways.
Chapter 13 Bones and Muscles
Movable Joints Activity
Click the Active Art button to open a browser window and access Active Art about movable joints.
Chapter 13 Bones and Muscles
Bones—Strong and Living
Bones are complex living structures that undergo growth and development.
Chapter 13 Bones and Muscles
End of Section: The Skeletal System
Chapter 13 Bones and Muscles
Section 3: The Muscular System
What types of muscles are found in the body?Why do skeletal muscles work in groups?
Chapter 13 Bones and Muscles
Types of Muscles
Your body has three types of muscle tissue: skeletal muscle, smooth muscle, and cardiac muscle.
Chapter 13 Bones and Muscles
Muscles at Work
Because muscle cells can only contract, not extend, skeletal muscles must work in pairs. While one muscle contracts, the other muscle in the pair relaxes to its original length.
Chapter 13 Bones and Muscles
More on Muscle Types
Click the PHSchool.com button for an activityabout muscle types.
Chapter 13 Bones and Muscles
Skeletal Muscles
Click the Video button to watch a movieabout skeletal muscles.
Chapter 13 Bones and Muscles
End of Section: The Muscular System
Chapter 13 Bones and Muscles
Section 4: Machines and the Body
How are force and work related?How does a lever make work easier?How do bones and muscles function as levers in the body?
Chapter 13 Bones and Muscles
Force and Work
A lever is a simple machine that makes lifting heavy objects easier.
Chapter 13 Bones and Muscles
Levers
A lever is a ridged bar that is free to pivot, or rotate, on a fixed point.
Chapter 13 Bones and Muscles
Levers
Levers are classified according to the location of the fulcrum relative to the input and output forces.
Chapter 13 Bones and Muscles
Mechanical Advantage
The input force and output force for three different ramps are shown in the graph.
Chapter 13 Bones and Muscles
Mechanical Advantage
Input force
Reading Graphs:
What variable is plotted on the horizontal axis?
Chapter 13 Bones and Muscles
Mechanical Advantage
400 N
Interpreting Data:
If an 80-N input force is exerted on Ramp 2, what is the output force?
Chapter 13 Bones and Muscles
Mechanical Advantage
5
Calculating:
Calculate the mechanical advantage of Lever 2.
Chapter 13 Bones and Muscles
Mechanical Advantage
Lever 1 produces the greatest resistance force in each case because it has the greatest mechanical advantage.
Drawing Conclusions:
Which lever produces the greatest resistance force when an effort force of 20N is exerted? Which lever has the greatest mechanical advantage?
Chapter 13 Bones and Muscles
Simple Machines in the Body
Most of the machines in your body are levers that consist of bones and muscles.
Chapter 13 Bones and Muscles
Links on Work
Click the SciLinks button for links on work.
Chapter 13 Bones and Muscles
Levers
Click the Video button to watch a movie about levers.
Chapter 13 Bones and Muscles
End of Section: Machines and
the Body
Chapter 13 Bones and Muscles
QuickTake Quiz
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