HOW SOME FAMILIAR THINGS LOOK 105 
Let us take a common kind of seed and 
see what the miscroscope can tell us about it. 
A fresh green pea is an excellent one to examine. 
When we cut it open and look at it under the 
microscope, we find that it contains a tiny plant. 
Inside the thin skin which covers it is a little 
root, a small stem, and two leaves, all folded 
together and practically filling the skin. The 
little leaves are green and made of rounded thin- 
walled cells. The cells are filled with starch, 
droplets of oil, fine grains of a whitish material 
known as albumin , and some green coloring 
grains. It is really a pea plant in miniature, 
with the food stored near it to feed it until it 
grows into an independent plant. 
The green pea itself is not grown up, how¬ 
ever. If it were allowed to develop, instead of 
being picked when it is fresh and green, the 
pod would finally dry up and burst open. The 
pea would be hard and dry, too, not at all like 
the soft tender green one we looked at. It 
would fall to the ground, and the moisture there 
would cause it to swell up and become green 
What is inside 
a green pea? 
Open pod 
Germination peas 
