ALAG, Alithea Digna M.PAREJA, Sheena Grace L. TAN, Jullienee Kristie A.RECONES, Vincent G.

Operculum Movement

“Determining the Effect of

temperature on the Operculum Movement of

Fishes”

Introduction:

Fish obtain their oxygen from water by ventilating their gills. These breathing apparatus are highly vascularized out pocketing of the body surface.  The operculum, a protective flap, covers and protects the gills, which are soft and delicate.  The gills are ventilated by pumping water across them in one direction.  Both the mouth and operculum work together to pump the water through the mouth, into the gills, and then out to the sides of the body.

As the water saturated with oxygen moves over the gills, gas from the water diffuses via the gills to the blood.  At the same time carbon dioxide moves from the gills out into the water.  The frequency of these “breathing” movements over a specific period of time provides a measure of the ventilation rate.

Genotypic and environmental variables both affect ventilation rate.  The effect of temperature on physiological processes has been well studied.  Fish are exothermic; their body temperature is the same as water temperature and changes directly with it. Many physiological processes, such as metabolic rate, heart rate, and enzyme activities occur faster as body temperature increases and slow down at colder body temperature.

Objective:

To determine the possible effects of water temperature to the operculum

movement of the fishes.

Hypothesis:

Ho : There is no significant effect of the change in water temperature to the operculum movement of fishes.

Ha : There is a significant effect of the change in water temperature to the operculum movement of fishes.

Variables:

Independent variable: Temperature of water

Dependent variable: No. of Operculum movement of fish

Controlled variable: Volume of Water

Materials:

• Liter Set (2)• Mercury Thermometer (2)• Water• Ice• Timer• Fishes (2)

Procedure:1. Gather all the materials needed for the

experiment.2. The fishes were placed in different liter set

filled with 8000 mL of water.3. Then the temperature of the water was

measured using a thermometer. The operculum movement of the fishes was recorded for one minute. The procedure was repeated two more times for it to have an accurate result.

4. Small amount of ice was then added to the liter set.5. Then we measured the temperature of the water in the

beaker.6. The operculum movement of the fishes was recorded

for one minute. The procedure was repeated two more times for it to have an accurate result.

7. Larger amount of ice was added to the liter set.8. We measured the temperature of the water in the

beaker.9. Again we recorded the operculum movement of the

fishes for one minute. It was repeated twice to have an accurate result.

RESULTS AND DISCUSSION

*No. Of operculum movement of fish per minute

Temp. in ˚C

No. of Operculum MovementAverage no.

of Operculum movementTrial 1 Trial 2 Trial 3

Fish 30 ˚C71 flaps per min.

87 flaps per min.

84 flaps per min.

81 flaps per min.

23 ˚C51 flaps per min.

28 flaps per min.

39 flaps per min.

39 flaps per min.

14 ˚C34 flaps per min.

29 flaps per min.

21flaps per min.

28 flaps per min.

After the students recorded the operculum movement of the fish in different water temperature, it was observed that when the temperature of the water is low, the operculum movement of the fishes is also low.

In the water which measured 30˚C, it was observed that the operculum movement of the fish was higher. It is because warm water contains less amount of oxygen, thus the fish breathes in a faster rate.

While in the water that measured 23˚C, it was observed that the operculum movement was lesser compared to the warmer water

The operculum movement of the fish in the water that measured 14˚C was slower than that of the other 2 setups.

It was also observed that fishes can’t stay long in very cold water.

Cold water has more dissolved oxygen than that in warm water. Thus the fish breathes faster in warm water in order to get oxygen. Based on the result of the experiment, the students can conclude that the operculum movement is higher in warm water and is lower in cold water.

REFERENCES:

• R. Edmondson, United States 2006• http://science.csustan.edu/flora/zool4232/Labs-S2010/

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