BIOLOGY EXPERIMENTS CHILDREN

(Jacob Rumans) #1

RAISING SEEDLINGS IN ATUMBLER GARDEN
Materials:Three dried lima beans, three dried corn grains, two glasses or
wide-mouthedjars, blottingpaper, papertowelling, tap water.
Follow this procedure:Soak the lima beans and corn grains for twohours
in a glass of water. -
Preparea "tumbler"or"pocket" gardenjustas you did in your study
of how gravity affectsplantgrowth. (See page 42.) Plantthe lima beans in
onejarand the corn grains in the second one. Keep them moist. Place the
gardensin a warm, darkplace(perhapsa closet) until green leavesappear.
You can watch the various stagesofgrowththroughthe glass.
You willobserve:The seed coatsofeach seed will split open. Rootswill
develop and grow downward. The stemsofbean seeds will arch upward,
pulling with them the cotyledons. The first green leaves will pop outfrom
between the two cotyledons. Then, the stem willstraightenup, and the first
pairofgreen leaves willappear.


The first leavesofthe corn seed will seem to bewrappedaroundthe stem.
They will growstraightupward. Unlike bean seeds, these have only one coty-
ledon which remainsattachedto the roots.

The embryos in seeds will grow into new plants only if they are provided
with moisture and moderatewarmth. We call thisgrowth stage, from the
embryo to the young plant seedling with its first green leaves,germination.
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