The leaves on the shoot are not at all chaotic. Their attachment to the axis of the aboveground part of the plant occurs only in certain places, which are called nodes, has its own laws. In our article, we will consider what the opposite arrangement of leaves is.
Layout Types
Leaf arrangement, or phyllotaxis, refers to a specific order of attachment of leaves to the stem. This feature is an important systematic feature. There are three main types: the next (spiral), whorled (ringed) and opposite leaf arrangement.
In the first case, only one sheet leaves the node. Relative to each other, they are arranged in a spiral. Examples of such plants are pear, rosehip, wheat and peach. With a whorled type, more than two leaves depart from the node. Such a leaf arrangement can be observed in pine, raven eyes, cypress, elodea.
Features of the opposite leaf position
The opposite type is characterized by the presence of two leaves in a node. Moreover, they are located opposite each other. As a result, a peculiar mosaic is created, which allows maximum use of sunlight. The opposite leaf position is considered a special case of whorled. Two plates are located in one node in such a way that their medians are in a single vertical plane.
Which plants have the opposite leaf arrangement
Naturally, the arrangement of leaves on the stem is not the only feature that determines the systematic position of the plant. But it is always used when describing species. So, the opposite leaf arrangement is typical for representatives of the families Honeysuckle, Labrum and Clove.
The first of them includes viburnum, elderberry, honeysuckle, musky grass, three-spruce, snowberry, linnaeus, and dirville. The Labretaceae, or Lamiaceae family includes mint, basil, sage, lemon balm, thyme, oregano, savory. Most of them are herbaceous plants. This family received the name Labret, due to the appearance of the flowers. They look like an open mouth.
Most representatives of the clove family are also grassy . They are used as fodder and ornamental crops, and some have found application in medicine. This is a smolevka, a soap dish, a dawn, a torus, a nap.
So, with the opposite leaf arrangement, two plates are located opposite each other in nodes. This feature of the structure is characteristic of cloves, honeysuckle and clear-leaved plants.