Donnerstag, 26. April 2007

How to find the preferred temperature of the animals - lab 12.03.2007

In the left Petri dish is ice water; in the right Petri dish is 60°C hot water. Then you put the bowl with one end on the cold Petri dish, with the other end on the hot Petri dish. After that you measure the temperature with a laser thermometer. If there is a temperature difference of 30°C you can put the animals into the bowl and you look at the animals in which direction they move.


The picture shows the bowl with the 2 Petri dishes.


The chart shows how the temperature is changing.


Observation of the animals
The animals were put at the zero point into the bowl and rested there for the first 10 seconds. After the 10 seconds the animals moved very quickly in colder areas of the bowl.
We wrote every 5 seconds down on which place the animals had been.
After 35 seconds all animals were in the colder areas of the bowl and rested there for the rest of the time.


The picture shows the animals in the bowl.


The chart shows where the animals have been in the bowl at different times.

Studying of the animals - lab 12.03.2007

Describe the animals in words
Flea crawfishes: like shrimps

Water woodlouses: like a normal woodlouse


Movement of the animals
Flea crawfishes: like dogs in water.
Water woodlouses: They move with their feet.


Put a sheet of a tree in the Petri dish to the animals

How is the behaviour of the animals changing?
The animals move immediately under the sheet.

The picture shows how the animals move under the sheet.

Conclusion of this observation

The animals do not like the light because they move immediately under the sheet, where it is dark.

How to make a temperature measurement device for animals - lab 12.03.2007

Materials
Sheet steel (100cm x 8cm)
Sticky tape
Yard stick
2 Petri dishes
Thermometer or Pyrometer
Hot water (ca. 60°C)
Salt
Flea crawfishes, Hüpferling, water snails, woodlouse


How to make a temperature measurement device for animals
You have to stick the sticky tape on the sheet steel, if not you could be hurt.
After that you have to bend the sheet steel to a bowl.
If you have finished that step you have to make marks in the bowl. The zero point is in the middle of the bowl and separates the hot and cold areas of the bowl.


The pictures show how you have to make such kind of measurement device.