BIOL 114
Ch 20: How Animals Move
20.1 Bulking Up Muscles
I.
Explain if you have increased the number of muscles cells since birth.
II.
Name two hormones that stimulate muscle cells to build proteins.
III.
Explain how myostatin plays a role in muscle protein production. That is, if an animal
has normal levels of myostatin, how do the muscles look? If an animal lacks myostatin,
how do the muscles look?
20.2 Skeletal System
I.
Types of Skeletons
A. Hydrostatic skeleton
1. Describe this type of skeleton.
2. Name a common animal found in soil that possesses a hydrostatic skeleton.
B. Exoskeleton
1. Name a noticeable characteristic of this type of skeleton.
2. Name a common animal with an exoskeleton.
C. Endoskeleton
1. Compare exoskeleton and endoskeleton.
2. Name a common animal with an endoskeleton.
II.
The Human Skeleton
A. Where are cranial bones found? Facial bones?
B. What material makes up intervertebral disks? As we age, what may happen to these
disks?
C. The rib cage is made of sternum and ribs. How many pairs of ribs do you have?
Which organs do the rib cage protect?
D. Name the bones of the pectoral girdle.
E. Upper Limb Bones
1. Where is the humerus?
2. Of radius or ulna, which one forms the elbow?
3. Name the bones in the wrist.
4. Name the bones in the palm.
5. Name the bones in the fingers.
F. Describe the purpose of the pelvic girdle.
G. Lower Limb Bones
1. Name the largest bone in the body.
2. Name the kneecap.
3. Of fibula or tibia, which one is not necessary for normal function?
4. Name the ankle bones.
5. Name the sole bones.
6. Name the bones in the toes.
III.
Bone Structure and Function
A. Bone tissue is made of bone cells that are within an extracellular matrix. Name the
main minerals that may be found in this matrix.
B. Where in a femur would compact bone be located?
C. Where in a femur would spongy bone be located?
D. Is red marrow found in compact bone or spongy bone? What is the purpose of red
marrow?
E. Where is yellow marrow found in limb bones? Yellow marrow is made of mostly
____________ cells.
F. Explain what osteoporosis is and how to prevent this disorder.
IV.
Where Bones Meet – Skeletal Joints
A. Fibrous joints
1. What type of tissue holds fibrous joints (such as those found in cranial bones)
together?
B. Cartilaginous joints
1. Where are cartilaginous joints found in the body?
C. Synovial joints
1. What type of dense connective tissue holds the bones in place in a synovial joint
such as the knee?
2. Using Figure 20.4 as a guide, what is are menisci in this joint?
D. Explain what a sprain is. Name the most common type of sprain.
E. Explain what a cruciate ligament is. What happens if these are torn? For the
equivalent sport, do men or women have more cruciate ligament injuries?
F. Why would dislocation cause pain?
G. Differentiate between osteoarthritis and rheumatoid arthritis.
20.3 How Bones and Muscles Interact
I.
Which type of tissue connects muscles to bones?
II.
Biceps as example muscle
A. The biceps muscle is attached at a fixed, immovable point to which bone?
B. At the other end, the biceps connect to which bone? As a result, when the biceps
contracts, how does your arm move?
III.
Are smooth muscle and cardiac muscle attached to the skeleton?
20.4 Skeletal Muscle Structure and Function
I.
Explain the relationship between muscle, muscle bundles, muscle fibers, myofibrils, and
sarcomeres.
II.
The regions that mark the ends of a sarcomere are called ___ lines.
III.
Differentiate between actin and myosin.
IV.
How a Muscle Contracts
A. In general, when a sarcomere contracts, which protein filaments are moving closer
together, thus moving the Z lines closer together, thus causing the shortening of the
sarcomere?
B. Steps in muscle contraction
1. When a sarcomere is relaxed, are the myosin heads and acting filaments touching
each other?
2. What happens to ATP molecules that are attached to myosin heads?
3. What happens to the levels of calcium within the muscle fiber? This calcium
allows the binding of the myosin head to the __________ filament. Note the
ADP and phosphate are attached to the myosin heads.
4. As the ADP and phosphate are released, how does the myosin head interact with
the actin filament?
5. How does the myosin head restore its original position?
V.
Getting Energy for Contraction
A. ATP is necessary for muscle contraction. Name the three ways that the body supplies
ATP.
B. How long should you exercise before fatty acids become the main source of fuel
during aerobic respiration?
20.5 Properties of Whole Muscles
I.
Muscle Tension
A. Describe a motor unit.
B. When nervous stimulation is sent to a motor unit, how many fibers in the motor unit
contract?
C. Do all motor units have the same number of muscle fibers?
D. When the muscle tension is greater than the load, does the muscle shorten and move
that load?
E. When the muscle tension is less than the load, does the muscle shorten and move that
load?
F. How can muscle fatigue be reversed?
G. What type of exercise helps increase a muscle’s ability to ward off muscle fatigue?
H. List some benefits of aerobic exercise.
II.
Impaired Muscle Contraction
A. Explain why males are more affected by Duchenne muscular dystrophy than females.
B. Poliovirus destroys motor neurons. How are skeletal muscles affected as a result?
C. The bacterium Clostridium tetani produces a toxin that continually stimulates motor
neurons. Describe some symptoms.
D. How does an individual usually die from ALS?