"Natural Science 4" is an interactive encyclopedia that includes scientific information in the understanding of fourth grade students, wonderfully illustrated and animated.
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* Chapter 2 Lesson 11 *
* Adaptation of plants *
Wherever you travel on our planet you will encounter a lot of plants. From the North Pole to the South Pole, from the lowest to the highest places, from the friendliest to the most hostile living environments, plants have learned to survive. How? They have managed to adapt to the conditions in which they live, changing over time their structures, the shape of their organs, their appearance or their way of life.
In the cold areas of the northern part of the planet where it snows heavily and where, for most of the year, the weather is cloudy and cold, the trees of the taiga forests have adapted to withstand these conditions. They have a pointed crown to allow the snow to slide down to the ground, and the waxy dark green leaves can absorb more energy from the sun.
Also as an adaptation to the cold, in the mountain meadows the plants have leaves covered with protective hairs or with wax and short or extended stems at ground level.
In winter, deciduous forests lose their leaves and stop growing. This allows them not to lose water and withstand the cold.
In places where the wind blows strongly, plants have roots deep into the ground or clump together. A forest withstands a strong wind much better than a single tree.
In very hot areas of the planet, plants have learned to live with a small amount of water. The cactus, also called the desert fountain, is a champion in this regard. Under the waxy covering of the stem, the cactus stores in its cells a large amount of water, which, when needed, can be used by those lost in the desert. The leaves turned into thorns to prevent evaporation of water through transpiration and to defend the plant from thirsty animals. Its long roots trap groundwater. Another adaptation of plants in dry areas is the short life cycle corresponding to the wet period.
In rapid mountain waters, plants cannot sink their roots into the soil, so green algae and water mosses are well fixed on the stones. In the quiet ones on the plains, water lilies grow with their roots firmly embedded in the mud. The long stem allows the plant to rise to the surface of the water where the leaf and its lovely flower float.
Seaweed grows along the beaches. Some of them have no roots because they have no soil to attach to. They take their food directly from the water. It clings to rocks with the help of crampons. Algae are pliable, adapting to water movements. Some of them, for example brown algae, have small air-filled bubbles that help them float in water. Algae can grow at different depths: sea lettuce can also live in the air, while sea grass forms true underwater forests.
What other spectacular plant adaptations do you know?