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What is a modified escape, examples and reasons for the formation


In botany, a plant has certain constituents. As a result of evolution, modifications of the shoots occur.

Content:

  1. Shoots - what is it
  2. Types and classification
  3. What are ground shoots of the modified type
  4. Characteristics of underground shoots with changes

Shoots - what is it

The shoot is the central organ of the plant, which has the ability to vegetate and grow. It is a stem with branches, stems and buds on it.

The main task of the shoots is the implementation of the respiratory function. The processes of photosynthesis, the formation of important organic substances and their transport into plant cells take place in the leaf plates.

The components of the escape are:

  • Stem. The base and support of the plant.
  • Leaves. Parts in lateral position. Between the stem and the leaf is the leaf axillary, above the leaf is the axillary bud.
  • Node. The area of ​​the shoot from which the leaf leaves.

There are also underground shoots. They store organic matter.

Types and classification

In botany, there are different classifications of shoots. How are they distinguished?

By function

Vegetative is responsible for gas exchange and nutrition, including the stem, leaves and buds.

Generative plays the role of reproduction, it includes a flower, fruits and seeds.

For the development of internodes

In shortened shoots, the growth of internodes is insignificant. The type is inherent in dandelion, plantain, primrose.

Internodes of elongated shoots develop rapidly.

By location in space

Erect ones grow upwards perpendicular to the ground. Typical for oats, poplar, sunflower.

Creeping shoots have a horizontal growth direction.

Ascending ones grow horizontally, then ascending vertically. Such shoots are in Potentilla.

Creepers grow like creeping shoots, but take root with adventitious roots. Striking examples are strawberries, strawberries.

Creepers include vines, bindweed, hops. Based on the name, it becomes clear that the shoots twine around supports or other plants.

Climbers are equipped with additional tools - suckers, antennae, thorns (ivy, grapes).

Also underground and aboveground modified shoots are known in botany. What they are, we will consider further.

What are ground shoots of the modified type

A modified shoot is a plant organ in which the standard functions (stem, leaves) have changed during evolution or as a result of human intervention. Metamorphoses can be small and significant, touching the stem, buds or leaves.

Aboveground shoots, in addition to the function of photosynthesis and gas exchange, support and reproduce. The whole part above the ground or its individual components can be modified. Examples of modified aerial type shoots:

Thorn

It is a short, sharp shoot without leaves. The thorns often play a role of reproduction or protection. With the help of them, the seeds of some plants are attached to the fur of animals in order to be transported over long distances.

In wild fruit plants (pears, apple trees), thorns perform a protective function. In the hawthorn, they replaced the lateral shoots.

Tendril

Shoots resembling bundles without leaves provide additional support. They are necessary for those representatives of the flora who are not able to stand upright themselves. Antennae are inherent in cucumbers, melon, pumpkin, blue passion flower.

Cladodius

The lateral shoot, subject to metamorphosis, capable of impressive growth, performs the functions of leaves. The shoots contain chlorophyll cells. The main task of the cladody is photosynthesis. The owners of such shoots are some cacti, prickly pear, southern karmichelia.

Phyllocladium

Phyllocladia, like cladodes, play an important role in photosynthesis.

It is a leaf-like lateral shoot that performs the functions of leaves and resembles them externally. Growth restrictions are noted. It is found in representatives of the Asparagus, as well as in phyllanthus, butcher's.

Characteristics of underground shoots with changes

Shoots that are underground, in contrast to terrestrial ones, have completely different living conditions. As a result of irreversible changes, new functions and capabilities are acquired: the ability to endure unfavorable times and accumulate organic matter. Aboveground modified shoots include.

Rhizome

An underground shoot with nodes, buds and additional roots. Carries out vegetation and stores the necessary nutrients. Examples are wheatgrass, iris, horsetail, lily of the valley.

Underground tuber

The main task of the tuber is the supply of vital substances. Equipped with leaves and axillary buds. Suitable for breeding. Jerusalem artichoke and potatoes have such shoots.

Bulb

Underground shortened shoot with a thickening from which adventitious roots grow. The stem is transformed into the bottom. Many owners of the bulb are representatives of the Liliaceae and Amaryllis families.

Garlic is also a modified shoot of this type. The bulbs are good for propagation.

Corm

Shoot with a thickened stem and adventitious roots. Covered with a protective layer of dry leaf bases. Corms, like most underground shoots, accumulate organic matter. Typical for gladiolus and saffron.

Claudex

A type of shoot, typical for grasses and shrubs with tap root systems. Claudex is equipped with kidneys, stores the necessary elements for vital functions. It is found in some Legumes, Umbrella and Compositae (wormwood, alfalfa, ferula).

Shoots are the most important part of plants. As a result of the need for an additional supply of food and protection from absorption by animals, certain metamorphoses occurred.

Now both wild and cultivated plants have modified shoots.

For greater clarity, we suggest watching an interesting video about modified shoots:


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