Perch Dissection

by Liz LaRosa

www.middleschoolscience.com

Objectives:

• to observe the external and internal anatomy of a perch.
• to determine the sex of a perch using internal anatomy.
• to collect statistical data on perch length

External Anatomy:

1. Draw a lateral view of your perch in Figure 1 : Find and label the five different types of fins: Caudal fin, Dorsal fin, Anal fin, Pelvic and Pectoral fins.  Be sure to label the operculum, dorsal, ventral, anterior and posterior!
2. Measure the length of your perch in cm from head to tail.  Record in Table 1
3. Make an incision along the ventral surface. Make a vertical incision behind the head, and another vertical incision before the tail.  Flip the skin upward.

Internal Anatomy:

1. Draw the internal anatomy in Figure 2 .  Label the following : stomach, air bladder,  liver, gills, heart, and any other structures you can identify. Be sure to label dorsal, ventral, anterior and posterior!
2. Determine the sex of your fish by looking for the gonads.

Table 1: Perch Data
 

Length of perch	cm
Sex of Fish	male/female

 

Figure 1: External anatomy diagram of the Perch. Lateral View.   Label all fins .
               Label the anterior, posterior, dorsal, & ventral.

Figure 2: Internal Anatomy of Perch. Lateral View.  Label all parts.

Figure 3: Stem and Leaf of Perch Length in cm (for all classes)

Table 2: Summary Data Table of Perch Length
 
 

n
max
min
range
sum
avg
med
Q3
Q1
IQR

 

1. What was the sex of your fish? How did you know?
2. What is the function of the air bladder?
3. Are fish warm blooded or cold blooded?
4. Where is the operculum? What is it's purpose?
5. How does the shape of the fish help it maneuver through the water?

Conclusion: 2-3 sentences on what you learned