WHAT PEOPLE ARE MADE OE 
39 
certain changes in its surroundings. Put it on a glass 
slide, then tap the slide sharply, and through the micro¬ 
scope you can see the ameba draw itself up still smaller; 
bring close to it certain chemicals, and it will come to 
them or shrink away; strong heat or light will damage it, 
and electric currents will cause it to move in a particular 
direction. 
Here is a picture of an ameba 
changing shape and flowing around 
food. You can see the cell-wall, 
the protoplasm, and the nucleus. 
The black spot outside the cell is 
a particle of plant which the ameba 
is going to eat. 
See how the ameba goes after 
his dinner! He has no hands to 
reach for it, so he stretches out a 
piece of himself and touches the 
particle of plant. If it were a 
Stone, Or Something he COUld not How Ameba Goes After 
His Dinner 
eat, he would shrink away from 
it immediately, but somehow this plant seems tasty to 
him, so he puts out another piece of himself and draws 
the food right into the protoplasm of his body. He di¬ 
gests as much of it as he wants, and then that clear 
space you see inside the protoplasm busies itself in pump- 
