Wednesday, September 21, 2011

Lazarus Experiment

For our science, we are using Apologia Press' Flying Creatures of the Fifth Day.

We are currently studying insects. One of the recommended experiments from the book is the "Lazarus Experiment" .

The first step is to 'drown' an insect. The book suggests holding it under water with a spoon. I thought it would be easier to drown it in an applesauce cup of water and use a second applesauce cup to hold it down.

It took a surprisingly long time for our grasshopper to stop moving and appear dead.

Oh, look the poor grasshopper drowned!!

The next step is to cover the insect in salt (the salt absorbs the water and speeds up the 'resurrection' but has nothing to actually do with bringing the insect back to life.

Now the poor grasshopper looks as if he were frozen in the snow. Poor little hopper. :)

After the salt has absorbed the excess water, blow the salt off of him.

It will take a while but eventually, your insect will revive.

Our textbook explains the results in this way "Why didn't the insect drown in the water? Well, insects are able to close the spiracles in their abdomen when faced with heavy rains or other unfortunate meetings with water. When they come out of the water and dry off enough, they can reopen their spiracles and breathe again!! The reason you used salt in the experiment is that it speeds up the absorption of water from the insect, causing it to start moving more quickly." (143)


Spiracle: Insects have little holes called spiracles all over their abdomen (there are some in their thorax as well) that allow air to enter their body. There are no muscles to push the air in and out; therefore it is a passive breathing system.


Judy said...

VERY cool.
And that close-up of the grasshopper face? AMAZING.

Phyllis said...

Oh, that is amazing!