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Autonomic Movements

It is the movement of the protoplasm. These are limited to aquatic plants and are free and spontaneous movements.

Examples: Streaming of cytoplasm (cylosis), movement of cilia or flagella, motility of zoospores.

movement by cilia
protoplasmic movements in amoeba

protoplasmic movements by streaming of  cytoplasm
protoplasmic movements by gliding

Protoplasmic movements(a) ciliary (b) amoeboid (c) cyclosis (d) gliding

 

Growth and curvature movements

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Higher plants and most other plants remain attached to one place and do not move from place to place like animals. They can only change the direction of their organs by means of curvature.

These movements take place due to the difference in the ratio of growth of different parts. It can be further classified as nutational or nastic movements.

i) Nutation

Movements as seen in twiners and climbers. This results in curvature and helps in twinning around the support.

example for nutation
Nutation

ii) Nastic Movements

These movements are due to differences in the rate of growth on two opposite sides.

Example: opening of the petals and circinately coiled leaves.

iii) Movement of Variation

Movement which takes place due to changes in the turgidity of cells.

Example: Desmodium gyrans or the telegraph plant. The elliptical up and down movement of the 2 lateral leaflets is due to change in the turgidity of the cell.

movement of variation in desmodium gyrans
Leaf of Desmodium Gyrans Showing Moving Leaflets



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