Page 91 - Science Class 06

Adap ve Features of Mesophytes Xerophytes

Since terrestrial plants have to take in water Xerophytes are plant species that have
and other nutrients from the soil. They have adapted to live in dry or desert condi ons.
well-developed roots with root hair. Roots Xerophytes have evolved to bear and
also help them to stay erect on the land. survive in extreme and harsh environments.

They can be found from the arid and hot
deserts of Africa to the freezing ice covered
Arc c.

For example, cactus of all types. Xero-phytes
have developed several adap ve features
due to dry and hot condi ons in their
habitat.
Trees have well-branched roots.
Adap ve Features of Xerophytes
v The stems of mesophytes are aerial,
solids and well-branched that help The roots of xerophytes are very long. They
grow as deep as possible in reach of water.
them in maintaining the balance.
For example, a xerophyte and alfalfa have
v The leaves of these plants are large, roots which may be more than 30 m long.
broad and thin. They generally live
Leaves of most of the xerophytes are highly
horizontally to get maximum sunlight
reduced and some mes absent.
for the process of photosynthesis.
For example, in Opun a, the leaves are
v The leaves of these plants do not have
modified into long slender spines and in
waxy coa ng so that they can trap air
Australian Acacia, the leaf pe ole behaves
and sunlight easily for photosynthesis.
like a leaf. This feature of the xerophytes
prevents water loss from the plants.

These plants have thick leathery covering on
Can a terrestrial plant survive if we put
oil or grease on its leaves? the stem to prevent loss of water through
evapora on called transpira on.
Take a small plant having a few leaves.
Now, take a small amount of grease and

put a layer of grease on the surface of
the leaves. Keep the plant in sunlight and
water it regularly for a few days. In a few
days you will observe that the plant is
dying.
It is because the grease do not allow the

leaves of the plant to take in air and
sunlight that hamper the process of
photosynthesis. Opun a

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