Keimblättern

Keimblättern, also known as cotyledons, are the embryonic leaves of a plant. They are the first leaves to appear from a germinating seed. In many plants, keimblättern serve as a temporary food source for the developing seedling, absorbing nutrients stored in the seed's endosperm or cotyledons themselves.

The structure and number of keimblättern are key characteristics used to classify flowering plants. Monocotyledonous plants, or monocots, have a single keimblatt. Examples include grasses, lilies, and orchids. Dicotyledonous plants, or dicots, typically have two keimblättern. This group includes a vast range of plants like beans, roses, and oaks.

In some species, the keimblättern remain below the ground during germination (hypogeal germination), while in others, they emerge above the soil surface (epigeal germination). Once the seedling develops true leaves, which are distinct from the keimblättern and are capable of photosynthesis, the keimblättern often wither and fall off. However, in certain plants, such as some legumes, the keimblättern may persist and even perform photosynthesis for a period. The presence and development of keimblättern are crucial for the initial survival and establishment of a new plant.