EXPERIMENT 4
14
Waterweed
chloroplasts
YOU WILL NEED
› 1 Slide, 1 cover slip, pipette, tweezers
›
1 Piece of blotting paper (or paper towel), 1
waterweed leaf, water
HERE’S HOW
1. Prepare the slide as already described in the
onion skin experiment (Experiment 3).
2. Use the tweezers to place the leaf in the
water droplet, and cover everything with a
cover slip.
1
EXPLANATION
The individual chloroplasts are easy to
spot inside the cells. They are constantly
in motion under the bright light of the
lamp. The green chlorophyll plant
pigment is important for
manufacturing sugar and starch,
which it does with the help of sunlight.
TIP!
Most leaves consist of sev
eral layers of
cells. That is why you first h
ave to cut
these specimens in order t
o get layer
thin enough for the light o
f the
microscope to penetrate. B
efore
practicing your cutting tec
hnique in the
next chapter, try finding o
ther types of
plants with similarly sim
ple tissue
structures. Moss leaves a
re ideal for
this. Or try “peeling off” t
hin layers
from the surface of other p
lant leaves,
such as cabbage or lettuce l
eaves (close
to the stalk), or from the s
tems of cut
flowers (e.g., tulips, gerbe
r daisies), or
the skin of a tomato.
