Watching Plants Move

Isba Fitri was working in the bushes. She was squatting down out of sight. Isba did not intend to hide herself during the lesson. She was observing the movement of a plant 'memosa pudica'.

MEMOSA PUDICA might sound unfamiliar to our ear. In Indonesia we know this plant better as putri malu. It can usually be found in the bushes. It seems that the plant really loves to hide in the midst of other plants. Ibu Znaidah Harahap, S.Pd a science teacher at SMPN 1 Angkola Barat, South Tapanuli, knows all about the habitat of the putri malu. That is why, when explaining to her students about the plant, she didn't just do it in her classroom. Instead, she asked her grade 8 students to find Memosa Pudica in its habitat. One student, Isba, swiftly navigated the thicket of weeds to find putri malu.

Not without reason Ibu Znaidah asked Isba to go out into the itchy weeds. Ibu Znaidah want Isba to oberve movement in plants. This movement is part of basic competency on identifying various kinds of movement in plants. Before going out to observe the plant, the students were prepared by the teacher. They were also equipped with some tools and a worksheet with questions on it. Isba was asked to touch the plant by using his pen. She touched the leaves, stalk, and stem. She observed the reaction of the plant, after touching it with a pen. And she also timed the reaction.

Before going out to observe the plant, the students were prepared by the teacher. They were also equipped with some tools and a worksheet with questions on it. Isba was asked to touch the plant by using his pen. She touched the leaves, stalk, and stem. She observed the reaction of the plant, after touching it with a pen. And she also timed the reaction.

Isba was not the only student who was deeply involved in this observation. Emil Iswandi, together with his group mates, did an experiment too. At the end of the experiment, Emil had drawn his own conclusion. First, putri malu will furl its leaves if they are touched. Second, the stalk will droop when it is touched. Third, the stem will go limp when it is touched. After ten minutes, the whole plant will recover. The leaves will open, the stalk will get firm and the stem will be stiff, wrote Emil in his report.

From the experiment Isba and Emil learned about plant movement. According to Emil plant movement is influenced by the stimulus. Though they had to work in the bushes to observe the plant, Isba, Emil and other students were happy to do the activity. 'Now we know what plant movement is,' they wrote in their reflective journals.

Phototropism in a Cardboard Box

Cika Feby Valentine got a new assignment. She had to plant some seeds, but in a cardboard instant noodle box.

CIKA, a 7th grade student, was assigned by Magatur Boru Marpaung, S.Pd, a science teacher at SMPN 4 Tebing Tinggi, to plant seeds. For seven days, Cika took care of her seeds. With the friends in her group, she had to water the seeds through the long germination period until the seventh day. The way Cika planted the seeds was unusual. She did not plant them in the soil. She used an empty noodle box. The equipment they were provided with were also unusual and included a small plate, cotton, 5 green beans, carbon paper and a knife. For a start Cika put the cotton on the plate, then she put five green beans on the cotton. The plate and the cotton were then placed inside the cardboard box.

When the plate was inside the box, Cika closed the lid. She used carbon paper to cover the carboard so that the light could not penetrate. However, she finished by making a 3cm-hole in the back of the box. The box was put in a dark place. Cika's plants were ready to grow. For seven days, Cika checked her beans. Everyday she watered them. She didn't want them to die of 'thirst'. On the seventh day, she was excited. Through the side of the box she could see white stalks and green leaves sprouting. Cika knew were called seedlings. The seedlings grew toward the light.

The seedlings helped Cika recognize the movement of the plant. This movement is known as Phototropism, when plants grow towards the light. This movement is part of the basic competency about identifying kinds of movement in green plants. At the end of this experiment Cika was satisfied. She could identify the phototropism movement. By using cheap and simple media (a cardboard box, cotton and a plate) she could understand why seedlings grow towards the hole in the box.