Darwin's experiments on phototropism. Animation showing the experiments carried out in 1880 by British naturalist Charles Darwin (1809-1882) and his son the British biologist and botanist Francis Darwin (1848-1925). They investigated the phenomenon of phototropism in plants, experimenting with young shoots in monocotyledons such as grasses. The tips of these shoots are called coleoptiles. The first animation shows a shoot's coleoptile bending towards sunlight. The second animation shows a shoot with its coleoptile removed and the plant not responding to sunlight. The third animation shows the same effect if the coleoptile is covered by an opaque cap. The fourth animation shows the coleoptile bending if the tip is covered by a transparent cap. These effects were described by the Darwins in 'The Power of Movement in Plants' (1880). Their observations led to the later discovery of the plant hormone auxin, which is produced in the coleoptile and causes these effects. For this animation with labels, see K004/3654. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Biocosmos / Francis Leroy & Michael Pierard |
Modell-Rechte: | nicht erforderlich |
Länge: | 35 Sekunden |
Seitenverhältnis: | 16:9 |
Restrictions: | - |