Download 13 Musculoskeletal System

Laboratory
13
Musculoskeletal System
(LM pages 173–186)
Time Estimate for Entire Lab: 2.5 hours
Special Requirements
1. Living material (order in advance for timely delivery): ATP muscle kit
2. Fresh material (obtain locally): long bone cut longitudinally (optional)
Seventh Edition Changes
This was lab 12 in the previous edition. The chapter was reorganized and presents the material more clearly. Section 13.3 The Skeletal Muscles replaces Macroscopic Anatomy of Muscles and Physiology of Whole
Muscles. The introduction to skeletal muscles has been rewritten. Observation: Joint Movements was
revised and includes three additional joint movements shown in a new illustration.
New or revised figures: 13.2 Anatomy of a bone; 13.5 Human superficial skeletal muscles; 13.6 Joint movements
MATERIALS AND PREPARATIONS1
13.1 Anatomy of a Long Bone (LM pages 175-176)
_____
fresh long bone, cut longitudinally; or model, long bone (Carolina 56-7375)
_____
slide, prepared: compact bone (Carolina 31-2952 to -2976 )
_____
slide, prepared: spongy bone (Carolina 31-2946)
_____
slide, prepared: hyaline cartilage (Carolina 31-2898)
_____
microscopes, compound light
_____
lens paper
13.2 The Skeleton (LM pages 177-179)
_____
adult human skeleton (or model)
Adult human skeleton. A number of articulated human skeletons are listed in the Carolina Biological
Supply Company catalog, as well as in other similar publications. The skeletons come in plastic and natural
bone, with and without cabinets and rod supports.
13.4 Mechanism of Muscle Fiber Contraction (LM pages 184-185)
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adult human musculature model (entire or torso)
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slide, prepared: skeletal muscle, l.s. (Carolina 31-3316 to -3328)
_____
microscopes, compound light
_____
lens paper
_____
rulers, plastic millimeter
_____
slides
_____
ATP muscle kit (Carolina 20-3525)
Adult human musculature models. A number of human musculature models are listed in the Carolina
Biological Supply Company catalog, as well as in other similar publications.
ATP muscle kit. The kit contains glycerinated muscle, ATP solution, KCl and MgCl2 solution, and ATP plus
KCl and MgCl2. These solutions are perishable and must be ordered for date of use.
1
Note: “Materials and Preparations” instructions are grouped by exercise. Some materials may be used in more than one exercise.
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EXERCISE QUESTIONS
13.3 The Skeletal Muscles (LM pages 179-183)
Observation: Antagonistic Pairs (LM page 182)
1. The biceps brachii flexes the lower arm.
The triceps brachii extends the lower arm.
2. The sternocleidomastoid flexes the head.
The trapezius extends the head.
3. The sartorius rotates the thigh.
The adductor longus adducts the thigh.
4. The iliopsoas flexes the thigh.
The gluteus maximus extends the thigh.
5. The quadriceps femoris group extends the lower leg.
The hamstring group flexes the lower leg.
Isometric and Isotonic Contractions (LM page 183)
Experimental Procedure: Isometric and Isotonic Contractions (LM page 183)
Isometric Contraction (LM page 183)
2. Is the biceps brachii or the triceps brachii located on the anterior surface of the upper arm?
biceps brachii
3. What change did you notice in the firmness of this muscle as it contracted? It becomes firmer.
4. Did your hand or forearm move as you pushed up against the table? no
5. Given your answer to question 4, did this muscle’s fibers shorten as you pushed up against the
tabletop? no
Isotonic Contraction (LM page 183)
2. If a muscle contraction produces movement, is this an isometric or isotonic contraction? isotonic
13.4 Mechanism of Muscle Fiber Contraction (LM pages 184-185)
Experimental Procedure: Muscle Fiber Contraction (LM page 185)
Table 13.3 Glycerinated Muscle Contraction
Solution
Length (mm)
Slide1
Slide 2
Glycerol alone
K+/Mg2+ salt solution alone
e.g., 15 mm
no change
e.g., 15 mm
—
ATP alone
Both salt solution and ATP
—
shorter length
no change
shorter lengrh
Table 13.4 Summary of Muscle Fiber Contraction
Substance
Function
Myosin
Actin
Thick filaments that pull actin filaments
Thin filaments that slide
K+/Mg2+ salt solution
Cofactors needed for myosin to breakdown ATP
ATP
Supplies the energy for muscle contraction
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LABORATORY REVIEW 13 (LM page 186)
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Is compact bone located in the diaphysis or in the epiphyses? diaphysis
Does compact bone or spongy bone contain red bone marrow? spongy bone
What are bone cells called? osteocytes
What are the vertebrae in the neck region called? cervical
Name the larger bone in the lower leg. tibia
What bones are part of a pectoral girdle? clavicle and scapula
Skeletal muscle is voluntary and striated because of the placement of actin and myosin
filaments.
Glycerinated muscle requires the addition of what molecule to supply the energy for muscle
contraction? ATP
What type of molecule are actin and myosin? protein
Does the quadriceps femoris group flex or extend the lower leg? extend
Does the biceps brachii flex or extend the lower arm? flex
What muscle forms the buttocks? gluteus maximus
Thought Questions
13. What bones protect the thoracic cavity? the thoracic vertebrae, the ribs, and the sternum
14. When you see glycerinated muscle shorten, what is happening microscopically? Actin filaments are
sliding past myosin filaments.