21-EDB-10 level 1

1. MODIFICATION OF
ROOT
Submmited by
Icelin Glora .S ,21-EDB-10

3. Modification of root
Some plant roots may be modified for special purposes in addition
to accomplishing the root’s basic functions.

4. Storage roots
Some plants store carbohydrates in the roots for use in case of emergency
or in preparation for the winter months, as some plants lose their leaves and are
unable to perform photosynthesis. Most of this storage in plants happens in the
roots, where it can be safe from animals and be preserved better than
aboveground. We are familiar with this strategy of food storage, as we animals also
store extra food as fat in our bodies to use in case of food scarcity.

5. Adventitious roots
Roots usually grow underground, but some modified roots
can grow above ground from the stem and they are called
adventitious roots. We will subdivide adventitious roots into prop,
buttress, and aerial roots.

6. Prop roots
Prop roots extend from the stem to the soil and provide extra
mechanical support to the plant and an increased absorption
capacity after they reach the soil.

7. Buttress roots
These modified wall-like roots are characteristic of some large
trees growing in the tropics, usually in shallow soils, providing the tree
extra mechanical support. Ceibas are great examples of trees with
buttress roots.

8. Aerial roots
Most orchids are epiphytic, meaning they grow on top of other plants,
like trees, and not in the soil. This means that their roots are not underground, but
grow along the surface of the bark. However, this does not mean they are
parasitic, as they are only using the tree as a place to grow and they still gather
the water and nutrients from the environment to be able to carry on their
photosynthesis. Orchid roots are covered in a thick layer of dead cells called
velamen, which looks whitish, that helps to retain water.

9. Adventitious roots
Roots usually grow underground, but some modified
roots can grow above ground from the stem and they are called
adventitious roots. We will subdivide adventitious roots into prop,
buttress, and aerial roots.

10. Parasitic roots
Some plants have specialized roots, called haustoria, that
penetrate other plants to steal water and nutrients. These plants are called
parasitic, but the level of parasitism differs among parasitic species. Some
parasitic plants steal water and are still capable of undergoing
photosynthesis to produce their own food, like the mistletoe plant. Other
parasitic plants are absolute parasites that do not even have chlorophyll to
be able to carry on the process of photosynthesis, meaning they must
obtain water and food from the host plant in order to survive.