See the adaptations of the stems and the function of each one.
The stem is a very important structure for the plant, because, in addition to being the structure where leaves and roots are inserted, it promotes the exchange of organic substances between these organs.
Some species of vegetables, throughout their evolution, had to adapt to the places where they lived in order to survive and some of these adaptations occurred in their stems.
The thorns are one of the adaptations of some plants. They are short structures, very resistant and with a very sharp point, which serve to protect the plant, keeping away animals that could spoil it. It is important to remember that the thorns found in rosebushes, paineiras, among others, are called acúleos and are not stems, but epidermal formations of the plant that do not have any type of sap conductive vessel. The stem has no defined position on the stem, while the spines are formed in the leaf axilla. We can find thorns in plants like lemon and orange trees .
Another adaptation that we can see in some plants are called tendrils, which can be found in climbing plants. The tendrils initially grow in a straight line and, when they find a support, they curl up, fixing themselves. These adaptations can be found in plants such as chayote , passion fruit, vines etc .
In addition to spines and tendrils, some vegetables have an adaptation called cladodes . The cladodes are found in plants that have lost their leaves during its evolution, in order to prevent the loss of water to the environment, especially in regions that have very dry climate. Because it has cladodes instead of leaves, the plant can save water that would be lost through evaporation. The cladodes are stems that look like leaves and are commonly green and flat. Usually its leaves are turned into spines, as in cacti .