Plant Parts

PLANT PARTS

Which matters most? There are over 300,000 different kinds of plant- and they sometimes look VERY different from each other. Even if plants LOOK different, really they're not. For example, most plants grow flowers. Even if their flowers look completely different, nearly all flowering plants have the same bits. Even plants without flowers (non-flowering plants) have most of the same bits as their flowery cousins. So almost all plants have the same parts. But which is the most important? Let's ask them and find out...

Seeds Where it all starts If seeds weren't here, there would hardly be any plants at all. How important is that? Let me explain... 1 Plants grow from a seed We're really patient. We can wait years before growing. 2 Seeds contain everything they need Even the tiniest seed contains everything that's needed to make a plant. The seed coat protects what is inside. The embryo will become roots, stems and leaves. The tiny food store fuels the seed's growth. 3 Water, warmth and light When we sense the right amount of water, warmth and nutrients, we seeds start to grow or germinate. Nine out of ten plants grow flowers. Most flowering plants grow from seeds. So without us seeds, most plants wouldn't exist!

Roots The multitasking part I'd really rather not talk about myself. I prefer to stay in the background. Or completely underground, actually. But if you REALLY want to know... As soon as my seed germinated, I sent a radicle down into the soil. It sucked in water and nutrients. As the plant grew, I sent out lots of little roots (with the cute name of rootlets). Once the plant gets taller, I stop it toppling over because roots anchor the plant in the ground. I also sometimes store fuel for the plant to use later. If you like to eat carrots, for example, you can thank me: carrots are plant roots. Yes, actually, now I think about it... I suppose those jobs ARE quite important.

Stems... Into the light Roots don't seem to think they're that important, but I KNOW I'm MOST important! As a seed grows roots, it also grows a stem. (Stems don't always look exactly like me, though.) The stem grows towards the light... until it is in sunshine. To survive, plants need some key things: water and nutrients, collected by roots light and a gas called carbon dioxide, collected by leaves. Without ME linking them together, the roots and leaves would be useless! Which makes me more important than them.

...and trunks The plant superhighway Tree trunks like me are actually giant, strong, woody stems. We are the biggest, best and most important of all. The tallest stems belong to my cousins, the coastal redwood trees. Their trunks can grow over 100 m tall. Trunks are a plant superhighway. They carry all kinds of important materials back and forth between the roots, branches and leaves. The trunk acts like a giant drinking straw, carrying water and nutrients from the roots to the leaves. Food from the leaves also travels along the trunk superhighway, to wherever it is needed. So we hold plants together, stop them being blown over, connect the roots and leaves, and move important materials around. No WONDER were the most important.