Plant movement-gerak pada tumbuhan

Someday in junior high school.
Mr. Fauzi open here class.
“Good morning students. How are you today ?”
“Good morning sir, I’m fine. Thank you, and you?”
“I’m fine too”
“Ok, today we will talking about new subject. Plant movement. Anybody know, what the meaning of plant movement ?”
Sir” a student put her hand up.
yes. Solikhin,”
“ Plant movement is movement by plant, but is different with our movement. We can move all of our body like hands, footh, etc and we can show that, but for us, plant movement are often make we confuse because we can show their move only with our eyes.”
“Good job. Your answer is right enough Solikhin. Well, students, please open your e-book, page 43 chapter 9th.
Movement is one kind of responses of an organism to stimulus. Stimulus can come from outside (external) or from the inside (internal)of the organism on primitive organisms,the ability to respond the stimulus is very simple which is called as irritability.
Plant has certain sensitivity to give response to the stimulus it is received.
Every stimulus that strikes plant will be replied by thae plant.This response
in from of movement from the parts of plant.
The Various Kind of Movement in Plant
Based on its stimulus,the movements in plant are grouped into three, those are autonomic (endogenous) movement, exogenous movement, and hygroscopic movement.

Autonomic (endogenous) movement
Autonomic (endogenous) movement that is not known yet its cause certainly but predicted this motion is caused by stimulus that comes from the body of plant other words,autonomic movement is movement that is not caused by external stimulus.
a. the flowing movement of cytoplasm in cell.
b. The bending movement of leaf bud because of difference of growth
c. Movement that is shown by plant when grows such as the growth of
root,stem,leaf,and flower.
d. The rotating movement of chloroplast to encircle cell in Hydrilla sp.
Hygroscopic Movement
Hygroscopic movement of part of plant that is caused by the influence of
the change of water level from its cells so happens nonhomogenouse
a.The breaking of dried nut fruit leucaena glauca castor Caesalipinia pulcherrima.
b.The opening of sporangium in fern as cause of the wrinkling of annulus cell.

Exsogenous Movement
Exogenous movement is plant movement that is caused by external stimulus from the plant body. The Various Kinds of Exogenous Movement in Plant:
1.    Nastic
Nastic movement is caused by stimulus. Nastic movement is separated into five kinds, those are photonasty, nictinasty, thigmonasty,thermonasty, and complex nasty. Nastic occurs due to the difference of turgor pressure.the easiest example is ’’sleep’’ movement shown by many of pea family (leguminosae). The sleep movement is called nyctinasty (nyktos= night).
1.1  Fotonasty
Photonasty is nasty movement that is caused by stimulus of sunlight. Example:
The opening and closing of Mirabilis jalapa at certain time when there is light.
1.2 Nictinasty
Nictinasty is nasty movement that is caused by dark condition (sleeping movement). The leaves of leguminous plants (Leguminosaceae) will be closed at night. The leaves will be open again in the morning. In addition to the atmosphere caused by the dark, the motion "sleep" of leaves can occur due to changes in turgor pressure in the leaf joints.
Example: The closing of compound leaves in Sesbania grandiflora, Leucaena glauca, at night.
1.3 Thigmonasti
Thigmonasti is nasty movement caused by mechanical
stimulation of touch or pressure. Tigmonasti term comes from the
Greek, which means that thigma touch. Motion tigmonasti with
seismonasti called. The example: the closing of leaves of
Mimosa pudica when touched.
1.4 Thermonasty
Thermonasti is nasty movement that is caused by temperature
stimulus. For example, tulip flower will develop if suddenly gets
temperature increment and close anymore if temperature
1.5Complex Nasty
Complex nasty is nasty movement that is caused by several factors altogether, such as sunligt, temperature, water and chemical substance.
The example, the opening and closing of stomata.

2.    Tropisme
Tropism is the movement of a part of plant organ in response to stimulus.the direction can be toward or away from the stimulus. According to the kind of its stimulus,tropism is separated into five:
a.    Phototropisme
Phototropism is tropism movement that is caused by the stimulus of sunlight. The example,the tip of plant that lies in room will bend to direction of incident light.

b.    Geotropism
Getropism is tropism movement that follows Eart gravitational force. Geotropism is divided into two, those are as follows.
-       Geotropisme positif.
Positive geotropism is geotropism movement that its direction is downward (going to Eart). The example the tip of root grows to the direction of gravitation
      - Geotropisme negatif.
Negative geotropism is geotropism movement that its direction is upward (leaving Eart). The example the tip of stem grows upward leaving grafitational force.
c.    Chemotropism
Chemotropism is tropism movement that is caused by stimulus of
chemical substances. Chemotropism is separated into two kinds,
those are as follows.
-       --Positive chemotropism
Positive chemotropism is chemotropism that its direction approaches source of stimulus. the example themovement of root to food substance in soil.
-       --Negative chemotropism
Negative chemotropism is chemotropism movement that its direction is leaving source of stimulus.for example, movement of laves poison.
d.    Thigmotropism.
Thigmotropism is tropism movement that is caused by stimulus
of touch to harder thing. This movement is called thigmotropism
(thigmo = touch). The example are Piper betle and cucumber.
e.    Hydrotropism
Hydrotropisme is the movement of plant root that is influenced by reservation of soil water.commonly,root grows straightly downward,but if in this direction is not found onough of water,then the root will grow bending to direction that has enough of water.
3.    Taxis
Taxis is transfer movement of all body to stimulus that its direction is determined by the stimulus. Based on the kinds of its stimulus,taxis is separated into two kinds,namely phototaxis and chemotaxis
a.    Phototaxis
  Phototaksis is taxis movement that is caused by stimulus of sunlight. For example the movement of chlorophyll to the surface that gets light and movement of spore that has flagella to the light place.

b.    Chemotaxis
Chemotaxis is taxis movement that is caused by chemical stimulus.for example movement of spermatozoid(part that is formed by plant)of moss and fern to ovum that is found in archegonium attracted to the sugar or protein that is produced by archegonium.

Courtesy :
Ida Rianawat

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