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EXERCISE
C1
Cat Muscular System
MASTER LIST OF MATERIALS
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Gloves
Safety glasses
Dissecting tools
Dissecting tray
Preserved cat
TIME REQUIREMENT
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Removal of the skin: 30–60 minutes
Identification of muscles: 1–2 hours depending on number of deep muscles
studied
Clean up: 15 minutes
LABORATORY PREPARATION
1. Set preserved cats and large dissecting trays in the lab. Supply heavy tags for
students to identify their cat.
2. Provide preservative in squeeze bottles or spray bottles for students to keep the
specimens moist.
3. Set up a disposal area with a biohazard container for discarding scrap tissue. Also
prep a cleaning station for washing trays and tools.
TEACHING TIPS AND STUDENTS’ MISCONCEPTIONS
Lab Activity 1 – Preparing the Cat for Dissection
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Demonstrate correct dissection technique for each tool, especially the blunt
probe.
Remind students to remove the skin in one piece so it can be wrapped around the
cat during storage.
Lab Activities 2 – 8 – Cat Muscles
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194
Instruct students not to tear tissue during the dissection. Only cut on the
specimen when it is called for in the procedures and it is verified by the
dissection team that the correct structure has been selected to cut.
Remind students not to use water to moisten the specimens, it will promote
bacterial growth and decay. Keep the specimen moist with the preservative.
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Dissection Exercise 1: Cat Muscular System
195
EXERCISE
C1
Answers to Questions
LABORATORY REPORT
A. Matching
1. J
2. I
3. F
4. B
5. H
6. E
7. A
8. C
9. G
10. D
B. Short-Answer Questions
1. The muscles of the cat neck are similar to human neck muscles. A V-shaped
sternomastoid arises from the sternum and inserts on the mastoid process of the
skull. A pair of sternohyoid muscles lie over the larynx and act to depress the
hyoid. The digastric muscles insert on, and depress, the mandible. The
mylohyoid and masseter muscles act to elevate the mandible. Deeper neck
muscles include the sternothyroid and thyrohyoid muscles.
2. The muscles of the cat forelimb are comparable to the forearm muscles in
humans. The biceps brachii and brachialis are on the cat’s ventral surface and,
with assistance from the epitrochlearis, act to flex the forelimb. On the opposite
side of the limb, the triceps brachii and anconeus muscles act to extend the
forearm.
3. The abdominal muscles of the cat are similar to those in humans. The ventral
surface is supported by three layers of muscle: the rectus abdominis is in the
central muscle where the external oblique, internal oblique, and transverse
abdominis muscles insert.
C. Labeling
Figure D1.13
1. sartorius
2. external oblique
3. external jugular vein
4. sternomastoid
5. sternohyoid
6. pectoralis major
7. clavodeltoid
8. pectoantebrachialis
9. pectoralis minor
10. latissimus dorsi
11. xiphihumeralis
12. external oblique
13. transverse abdominis
14. linea alba
15. rectus abdominis
16. internal oblique
D. Analysis and Application
1. The single trapezius in humans occurs as three distinct muscles in cats; the
spinotrapezius, acromiotrapezius, and the clavotrapezius. The prefix of each
muscle describes the insertion. The single deltoid in humans also occurs as three
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196 Instructor’s Manual for Laboratory Manual for Anatomy & Physiology, Fourth Edition
muscles in cats; the spinodeltoid, acromiodeltoid, and clavodeltoid.
2. In cats there are four subdivisions of the pectoralis muscle group, but only two
divisions in humans. The superficial pectoantebrachialis is not found in humans.
Posteriorally, the pectoralis major and pectoralis minor muscles are similar to the
human pectoralis group. A thin xiphihumeralis occurs along the posterior edge
of the pectoralis minor. This muscle does not occur in humans.
3. The muscles of the cat thigh and lower leg are like the muscles of the human leg.
The sartorius, gracilis, tensor fasciae latae, gluteal muscles, adductor group,
pectineus, quadriceps femoris, and hamstring group are alike in cats and humans.
The iliopsoas in cats is a single muscle compared to the two-part iliopsoas in
humans. The caudofemoralis in the cat thigh is not found in humans. The lower
leg muscles are also similar among cats and humans. The gastrocnemius and
soleus muscles extend the foot while the tibialis anterior and peroneus brevis flex
the foot.
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