Basic organ

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In plant morphology , the basic organs are the stem axis , leaf and root . The basic organs cannot be derived from one another, "they cannot be homologated and they perform different basic functions". They are basic organs because all other organs can be derived from them. Their position in the structure "is always the same with the cormophytes : leaves are always on the shoot axes, never on the roots".

The term basic organ comes from Alexander Braun : “So stalk, leaf and root appear to us as essentially different parts of the vegetal organism, as basic organs of the same, based on the different directions in which plant life forms. Their sure and sharp distinction is the foundation of morphology. […] Leaves and stalks belong together, as we have noted above, opposite to the root as a whole […]. ”Braun assumes the duality root-shoot and then distinguishes axis and leaf on the shoot.

If the functionality is emphasized, then there are, on the one hand, the two axes of the stem axis and the root axis, the root axis aligns with the stem axis through secondary growth. On the other hand, we have the leaf on the stem axis and the root hairs and root cap on the root axis in the area of ​​the root tip.

Julius Sachs emphasizes duality and, in addition to the basic vegetative organs, differentiates between the basic reproductive organs. He comes down to three organ categories: “1) The vegetative organs: root and shoot. Inside the reproductive organs: 2) The sporangia with the spores. 3) The gametangia : the female archegonia and the male antheridia . "

literature

  1. ^ Eduard Strasburger ; Peter Sitte: Textbook of botany for universities . 33rd edition, 1st complete Reprint / rework by Peter Sitte… Fischer, Stuttgart [u. a.], 1991.
  2. ^ Andreas Bresinsky, Andreas; Eduard Strasburger: Textbook of botany . 36th edition Heidelberg [u. a.]: Spektrum, Akad. Verl., Heidelberg 2008
  3. ↑ Alexander Braun: Considerations on the appearance of rejuvenation in nature, especially in the life and educational history of the plant . University printing press, Freiburg 1850
  4. ↑ Julius Sachs: lectures on plant physiology . Leipzig: Wilhelm Engelmann Verlag, Leipzig 1882