Answers to Dissection Questions:
The first major difference between the perch and the other phyla is the endoskeleton. Everything else has either no skeleton, some chitin, or an exoskeleton. The fish has the same complexity of organs as an insect from the phylum Arthropoda. Other than that, the fish is similar to the other complex phyla. It has fin propulsion as a form of locomotion, which is a difference.
- The general body shape of a perch is very tapered. The width of the perch is quite small, but it is long and tall. The front tapers off to the mouth, and the back tapers to the rear fin. This adaptive body shape allows for smooth and fast navigation through water. The fins allow turning, propulsion, and control as well.
- One function of the gill rakers might be to filter out alien particles, or non-water particles.
- The pectoral and pelvic fins are used to control the direction of movement; the dorsal fin is used to stabilize the fish and aid in sharp turns; and the caudal fin provides thrust for forward movement.
- The scales of the perch face back for the effect of protection while maintaining fluidity and reducing drag.
- The perch has two nostrils. They are different because they ONLY lead to olfactory organs, and are NOT used for breathing.
- They are present in the organism, and they can filter out the oxygen from the water without water getting in.
- The lateral line is a sense system that runs down the fish. It allows the perch to feel movement and vibrations around it.
- It's protected, and it protects the organs better.
- The guppy produces fewer eggs. For birth, guppies have a higher survival rate (as perch eggs are commonly eaten by predators), but if a higher percentage of perches survive, there is obviously a great increase in survival rate.
- The swim bladder allows the perch to change altitude and float.
- It's darker the farther down you go in the ocean, so the luminescent molecules allow for sight and navigation in the depths.
The first major difference between the perch and the other phyla is the endoskeleton. Everything else has either no skeleton, some chitin, or an exoskeleton. The fish has the same complexity of organs as an insect from the phylum Arthropoda. Other than that, the fish is similar to the other complex phyla. It has fin propulsion as a form of locomotion, which is a difference.