In this interview item, students were presented with the textual representation that depicts the process of photosynthesis (see the textual representation in figure 7.3). Students were given a period of time to read the text and then were asked to describe the entire process of photosynthesis. Besides, their comments were sought on the particular advantages (if any) to learn with the textual representation.
Figure 7.3 Text used in the complementary function
Table 7.5 shows students’ interpretation of the text, the result can be classified into two categories: 63.64% of the interview participants’ response (PRT1) includes the correct and the most complete answers, in which all factors relevant to photosynthesis have been mentioned by the interviewees. 36.36% of the participant’s responses (PRT2) refer to the answers that are correct but not complete. The students who missed one or two participating substances are classified under this category. This result may be explained by the fact that although most students could understand the majority of the photosynthesis process suggested by the textual representation, some others failed to give a complete and detailed description about this biological concept.
Table 7.5 Coding for Students’ Responses of The Meaning by Learning the Text in Interview Item -Photosynthetic Rate
Code Explanation Number
(Percentage) PRT1 Photosynthesis happens in plants. Plants use chlorophyll to
absorb light energy and then using carbon dioxide, water and light, the plants turned all these into chemical energy as waste products, such as glucoses, oxygen, and water.
7 (63.64%)
PRT2 The process of photosynthesis basically converts solar energy into chemical energy and stored in the cells. The products of this process include oxygen and water.
4 (36.36%)
7.3.1.1 Students Classified as Having a Complete Understanding
Seven students could give a correct and complete answer about the content of photosynthesis shown by the text (coded as PRT1). Being correct means that was no alterative conceptions could be found in the student’s response. Also being complete refers to the student providing a thorough description about his/her understanding of the biological concept that contained all the terminologies and information been given.
Interviewer: Can you explain the biological knowledge shown by the text?
Student 1: It is in plants. It doesn’t say in here, but I know it is in plants. Plants use chlorophyll to absorb light energy and then using carbon dioxide and light, they turned the light energy into chemical energy, they store in the glucoses and they produce oxygen, water as waste products.
Interviewer: What are the factors that can be affecting the photosynthesis rate?
Student 1: the light, the chlorophyll in the plant, water, and any carbon dioxide present in the atmosphere or environment.
The complete and correct interpretation can also be found in student 2’s response: Interviewer: Please explain the process of photosynthesis suggested by the text? Student 2: The chlorophyll absorbs light, carbon dioxide and water, and transforms
them into the glucoses, oxygen and more water.
Interviewer: Which one is glucose? [The glucose was written as C6H12O6 in the text] Student 2: So this is glucose.
Student 2: I do chemistry as well, and that’s carbon dioxide, water, oxygen. [Student 2 pointed CO2, H2O and O2 respectively]
Interviewer: Can you explain the photosynthesis from the very beginning?
Student 2: It converts solar energy into chemical energy, in which it stored in the molecules. Then it releases the oxygen as a waste product, and absorbs carbon dioxide.
Interviewer: Any chemical substances participate in this process? Student 2: Chorophyll, Carbon dioxide and water.
Interviewer: What do you think are the factors affecting photosynthesis rate? Student 2: Sun is available, carbon dioxide availability and water.
Student 1 and student 2’s responses show that they both have gained scientific understanding about the concept of photosynthesis, that is, solar energy has been transformed into chemical energy. The participating substances are carbon dioxide, water, sun light and chlorophyll. The process produces glucose, oxygen and water. Their responses were considered to be complete because they used all the information in the text to depict their understanding. No chemical substance has been missed out.
However, some students’ responses were considered to be less complete, though they did not show any alternative conceptions toward this biological concept. The reasoning from Student 4 and student 10 seems to be less complete, because they did not mention one or some of the substances in their explanations.
Interviewer: Please explain the process of photosynthesis shown by the text?
Student 4: Plants use light energy and then turned the light energy and carbon dioxide into chemical energy, they produce waste products like oxygen and water.
Interviewer: what are the factors that can affect the photosynthesis rate?
7.3.1.2 The Response from Another Student That Has Been Coded as PRT2:
Interviewer: Can you please explain the process of photosynthesis shown by the text? Student 10: Um, the plant absorbs carbon dioxide from the air and along with the
water, with the presence of light and chlorophyll, it can produce glucose and oxygen as a waste product.
Interviewer: So what colour is chlorophyll? Student 10: Green.
Interviewer: Green. What do you call this? [The researcher pointed at the C6H12O6 in
the equation] Student 10: Glucose.
Interviewer: Glucose. What is the glucose for? Student 10: For energy... ... for the plant to grow.
Interviewer: What do you think are the factors that can affect the photosynthetic rate? Student 10: The light, the temperature, um...
Student 10’s response has been classified under the category of PRT2, because she missed one product of the chemical reaction – water. Similarly, other students from the category PRT2 had missed one or two substances in their answer.
7.3.2 STUDENTS’ COMMENTS ON LEARNING WITH TEXTUAL