Page 1 - 3. The Shoot system, Modifications of stem
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SAI International School
                                              Subject- Biology, Class-VI

                                               Topic- The Plant World
                               Subtopic- The Shoot System, Modifications of Stem
                                                     Lesson Notes


               The Shoot system:

                   •  The shoot system is the part of the plant found above the soil.
                   •  It bears branches, leaves, buds, flowers and fruits.
                   •  The stem is the main part of the shoot system
                   •  Nodes and internodes are the two important parts of the stem.
                   •  A node is a place where a leaf, a branch or a bud arises.
                   •  The portion of a stem between two nodes is called an internode.


               Functions of a stem:
                   •  Stem keeps the plant upright.
                   •  It helps in the transportation of water and mineral salts from the roots to the leaves
                       and likewise transports food prepared by the leaves to all the parts of the plant.
                   •  The stem also supports the other parts of the shoot. Leaves are so arranged that
                       they are well exposed to sunlight.


               Modifications of the stem:
                   •  Support: The stem is modified to form a tendril in some plants. These tendrils coil
                       around any rough surface they come in contact with and provide support to the
                       weak stem. These tendrils are also called climbers or twiners.
                   •  Storage: The stem can also be modified to store food as seen in the ginger, potato
                       and onion.
                   •  Making Food: In plants such as the cactus, the stem becomes green and fleshy and

                       prepares food for the plant. It also stores water in it.
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