Types of stem

All plants have stems , with the exception of bryophytes . It is the main organ of support  and conduction  of the plants and interconnects the roots, leaves, flowers and fruits.

In addition, the stem lifts the leaves, improving light absorption and, consequently, the performance of photosynthesis .

Trunks

These are the most common and diverse stems. They are woody, generally erect, with branches and, with leaves , form the crown of the trees.

Stems – Trunks of Sequoias, the largest trees on the planet.

Stipe

Long stem, erect and without branches, has leaves at the apex. This is a common stem in monocots .

Stem – Estipe – Imperial Palms of the Botanical Garden of Rio de Janeiro.

Thatch

Cylindrical stem with well-marked knots and internodes. It can be hollow as in bamboo or filled as in sugar cane.

Stem – Hollow bamboo stem

Stem – Hollow bamboo stem Stem – Stalk filled with sugar cane Stem – Stalk filled with sugar cane

Stem

Stems are usually photosynthetic throughout their life. This type of stem is typical of herbaceous plants.

Stem – Stem in herbaceous plants

Rhizophore

This stem is characteristic of mangrove plants, its main characteristic is positive geotropism , that is, it grows towards the soil, in the direction of gravity.

This favors the appearance of adventitious roots that are important for the oxygenation of the tissues of these plants.

Stem – Rhizophore in mangrove

Stolon

The stolon is a creeping stem that grows close to the ground. It has buds in the nodes that can originate roots and leaves, thus forming new  plants.

Stem – Stolon in strawberry plants

Sarmento

This is also a creeping stem that has only one fixation point with a root. The vine can climb on supports and have modifications such as tendrils.

Stem – Sarmento in pumpkin plant

Cladodium

Cladodium is an aerial stem adapted to make photosynthesis and store water. It is usually flattened to increase the absorption surface of sunlight and its growth is unlimited.

Stem – Cladodium in cacti

Philocladium

This is also an aerial stem adapted to be photosynthetic, but it does not store large amounts of water.

He t in  axillary branches with particular growth and  appearance of paper. However, despite the appearance, it is important to note that there are nodes in the middle of this structure, which makes it a stem.

Stem – Filocladium in a plant of Ruscus sp.

Bulbs

Bulbs are underground stems , flattened into a disk shape. They are formed by two parts: the dish, which is the stem itself, and  the  catafilos, modified leaves that accumulate substances.

Stem – Bulb on onion

Pseudobulbs

Pseudobulbs are aerial stems typical of orchids. They can be of various sizes and have water storage tissue, allowing orchids to establish themselves even in environments with water deficit.

Stem – Pseudobulb in orchid

Tubers

Tubers are underground stems that specialize in storing substances that serve as energy reserves, usually starch.

Because they contain these substances, they are usually juicy and many of them edible.

Stem – Tuber in English potato plant

Rhizomes

Rhizomes are also underground stems, they grow horizontally in the soil and can branch easily. The buds present in the nodes can give rise to leaves and roots and form a new plant.

Stem – Rhizome in ginger plant

Aquatic

The water stem can be completely or partially under water. Usually they have a large part of their structure occupied by a tissue that stores air, the aerenchyma. His presence helps in the fluctuation and maintenance of oxygen within the plant.

 

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