Sonali Sundar Reward Points : 10500 Member Since : Tuesday, November 20, 2007
What is the reason of collpase of leaves in a touch me not plant when someone touches the leaves.
Posted On : 3/31/2009 3:09:12 AM
Umesh Upadhayay Reward Points : 31200 Member Since : Tuesday, December 25, 2007
The leaves of the TOuch Me Not plant protect themselves by performing a disappearing act by closing its leaflets whenever touched. the reason is unique When a grasshopper or a locust lands on the plant, the rows of feathery, small leaflets that rise from either side of the mimosa s stems, suddenly fold upwards and appear like unappetising twigs. If this does not make the insect lose interest and fly away, the leaves make a downward movement to expose their thorny stems, thus baffling the insect and driving it away.
Posted On : 3/31/2009 10:58:42 PM
Suparna Sen Reward Points : 26200 Member Since : Saturday, March 14, 2009
Touch Me Not leaves closes when touched. The botanical name is Mimosa Pudica, Pudica means shy, in Kannada it is known as Muttidare Muni and in Hindi it is known as Chui Mui . This perennial creeper grows as a weed in all over India. It belongs to the family Mimosaceae, and the stems of these plants are prickly with small, fluffy ball shaped lilac flowers. The touch-me-not name comes from the plant s habit of flicking its seeds with a coiled action when ripe and brushed against. The body receptors of Mimosa pudica respond to touch. They respond whenever their shape is altered or distorted and trigger extremely sensitive fast firing neutrons. The opening and closing of the plants leaflets and the entire leaf are controlled by a fluid filled sac-like structures which is found at the base of the compound leaf and each leaflet. The swollen base of the touch me not leaf stalk is called pulvinus . When the plant is touched, electrical signals are flashed by the cells. The cells in the pulvinus respond to this signal by flushing out potassium and water. With the massive loss of water, the pulvinus bends over and the leaflets fold.
Posted On : 4/2/2009 4:36:26 AM
Anju Malhotra Reward Points : 61200 Member Since : Tuesday, March 31, 2009
Rapid plant movement encompasses movement in plant structures occurring over a very short period of time, usually under one second. For example, the Touch me Not plant and the Venus Flytrap closes its trap in about 100 milliseconds.The Dogwood Bunchberry s flower opens its petals and fires pollen in less than 0.5 milliseconds. The record is currently held by the White Mulberry tree, with flower movement taking 25 μ s, moving petals to velocities in excess of half the speed of sound- near the theoretical physical limits for movements in plants. These rapid plant movements differ from the more common, but much slower growth-movements of plants, called tropisms.
Posted On : 4/3/2009 1:50:09 AM
Maniam PS [Guru] Reward Points : 142500 Member Since : Wednesday, March 18, 2009
Mimosa pudica Sensitive Plant pudica = shy , is a creeping annual or perennial herb often grown for its curiosity value: the compound leaves fold inward and droop when touched, re-opening within minutes. The species is native to South America and Central America, but is now a pantropical weed. The stem is erect in young plants, but becomes creeping or trailing with age. The stem is slender, branching, and sparsely to densely prickly, growing to a length of 1.5 m 5 ft . The leaves of the mimosa pudica are compound leaves. The leaves are bipinnately compound, with one or two pinnae pairs, and 10-26 leaflets per pinna. The petioles are also prickly. Pedunculate stalked pale pink or purple flower heads arise from the leaf axils. The globose to ovoid heads are 8-10 mm in diameter excluding the stamens . On close examination, it is seen that the floret petals are red in their upper part and the filaments are pink to lavender. The fruit consists of clusters of 2-8 pods from 1-2 cm long each, these prickly on the margins. The pods break into 2-5 segments and contain pale brown seeds some 2.5 mm long. The flowers are pollinated by the wind and insects Mimosa pudica is well known for its rapid plant movement. In the evening the leaflets will fold together and the whole leaf droops downward. It then re-opens at sunrise. This type of motion has been termed nyctinastic movement. The leaves also close up under various other stimuli, such as touching, warming, blowing, or shaking. The stimulus can also be transmitted to neighbouring leaves. These types of movements have been termed seismonastic movements. The movement is caused when the leafs lose turgor pressure. Turgor pressure is the force that is applied onto the cell wall by water and other cell contents. This allows the plant to stay upright, but when it is disturbed by a stimuli, chemicals in the plant force the water to leave the cell. When this pressure is lost the result is a sagging plant. This characteristic is quite common within the Mimosaceae family. It is not known exactly why the Mimosa pudica has this feature but many scientists think that the plant uses its ability to shrink as a defense from predator. Many animals may be afraid of such a fast moving plant and would rather go and eat a less active one.
Touch Me Not Plant
