Probing students’ conceptions concerning homeostasis of blood sugar via
concept mapping
Shu-Nu Chang
E-mail: [email protected]
Mei-Hung Chiu
E-mail: [email protected]
Graduate Institute of Science Education
National Taiwan Normal University
Abstract
The purpose of this study is to investigate 7th and 9th-graders’ conceptions about
homeostasis of blood sugar. There are many studies revealed the difficulty to learn the
concepts of homeostasis. Concerning the concepts of homeostasis, homeostasis of
blood sugar is one of integrated topics in biology courses in junior high school. For
the moment, few studies were conducted to investigate it. In this study, we used semistructured interview and adapted concept map as a strategy to probe students’
conceptions of homeostasis of blood sugar (CHBS). After interviewed 14 students, we
found that both groups of 7th and 9th-graders severely lacked the conceptions of neural
system. Otherwise, 7th-graders had more integrated conceptions, no matter in
endocrine system, digestion system, or the mechanism for regulating blood sugar. In
the meanwhile, we discovered students liked to use external behavior or life
experiences to explain the mechanism responsible for CHBS. Besides most students
did not understand the micro phenomenon concerning CHBS.
Introduction
The researches of students’ conceptions have become the mainstream after
Ausubel brought up the idea of how the preconception influences the learning of
scientific knowledge in 1968. The role of conceptions in constructing human
knowledge has been enhanced in science education (Novak, 1988). However, it is
quite difficult to build up an integrated knowledge structure across fields in the
textbook. Once we make it, plenty and complicated content must be included in the
text book (Chi, Leeuw, Chiu, & Lavancher, 1994). Therefore some researchers in
science education address on investigating students’ pre-conceptions and
misconceptions for improving students’ learning. This is the main reason why we
would like to investigate students’ conceptions in this study.
In Taiwan, the concepts of physiology occupy almost half of time in biology
courses in junior high school. Among these concepts of physiology, homeostasis is the
most important topic, since it is the core concept across other knowledge of biology.
Besides, AAAS (American Association for Advancement of Science) has brought up
four comprehensive and more abstractive subjects today, which are systems, scales,
homeostasis and models (Penner, 2000). Furthermore, from teachers’ perceptions, the
homeostatic system has been addressed as one of most difficult topics in biology
1
(Fred, James, & William, 1982). On the basis of the statements above, it is not hard to
discover how important and difficult the concept of homeostasis is, no matter in
teachers’ or researchers’ perspectives. Concerning the biological content in junior
high school in Taiwan, the homeostasis of blood sugar is an comprehensive subject,
since it engages the concepts of endocrine system (ES), neural system (NS), digestion
system (DS), and the concept of homeostasis. In other words, the homeostasis of
blood sugar includes three kinds of comprehensive topics mentioned by Penner
(2000), which are systems, homeostasis and models. Accordingly, we chose
homeostasis of blood sugar as the main topic to explore in this study.
As of late, concept map has been adapted to many studies respecting science
instruction, learning tools, and evaluate students’ conceptions (Horton, 1993; Kinchin,
2000; Markham & Others, 1994; Okebukola, 1992; Soyibo, 1995; Stewart & Others,
1979). Hence we applied concept mapping as a strategy to explore students’
conceptions as well. In this study, we focused on the path analysis to investigate
whether any main concept or path is deficiency.
The purpose of this study is to investigate students’ conceptions after learning
the homeostasis of blood sugar, and to analyze the differences between 7th and 9th
students’ conceptions. The research questions were (a) what do students understand
about the mechanism of the homeostasis of blood sugar? Is there any difference in the
patterns of concept maps? (b) What kind of misconceptions do students keep after
learning?
Methods
Total 14 students participated in this study. Nine 7th-graders who were from three
different junior high schools and five 9th-graders were from one comprehensive high
school to join this study. There were no limitations in genders. In our study, we
applied the method of semi-structured interview for 30 minutes individually and
accompanied with asking students to do concept mapping while answering the
questions. During the period of the interview, we provided small cards to students,
and some of the cards had already presented the specific terms, such as “blood sugar”,
“ascension of blood sugar”, “descent of blood sugar”, and so on. Besides, students
could write their own answers on the blank cards. We requested students to arrange
their own concept maps while they answered the questions in sequence, and could
change the positions of the cards in between. The texture of the content and questions
were from the textbook edited by Ministry of Education (MOE) of Taiwan, which was
published in 2000. The whole processes of interview were audiotaped, and transcribed
to the protocols for further analysis.
Findings
In our preliminary analysis, we categorized students’ concept maps into six
different patterns, and compared the differences of students’ conceptions. Conceptions
of NS are most insufficient in both 7th-graders and 9th-graders were revealed.
Otherwise, 7th-graders had more completed conceptions than 9th-graders, no matter in
ES, DS, or the concept of the homeostasis. Moreover, we analyzed students’
transcripts and found students preferred to use external behavior or life experiences to
answer the questions about the mechanism responsible for homeostasis of blood
sugar. Simultaneously students didn’t have the idea of micro phenomenon about the
matters, which exchange in blood circulation. The following are the transcripts.
2
I. Answer with external behaviors
_1_Researcher: Is there any way to increase our blood sugar?
S212: Eat foods.
_2_Researcher: What is called homeostasis of blood sugar?
S331: Eat three meals per day regularly.
II. Answer with life experiences
_1_Researcher: Why does blood sugar exist in our body? What is the
function of blood sugar?
S212: What is the function of blood sugar……if we didn’t have blood
sugar, we would faint.
_2_Researcher:? What will be the result when blood sugar is too high in
our body?
S331: We will become fat, then uric acid will increase following.
III. Deficient of micro phenomenon of insulin
Researcher: Why is blood sugar high with diabetic patients?
S311: Because cells in their body couldn’t absorb sugar….
Researcher: Why can cells not absorb sugar?
S311:…?
Researcher: Don’t you know it? Is it possible that there is some places
of body got problems?
S311:…I don’t know.
IV. Misconception of circulation system
Researcher: You mentioned sugar will be taken out for use, and how
can we make it?
S212: How should I say…? Is there any method …system…circulation
system would know.
Researcher: What is circulation system?
S212: blood…blood?? Well…I don’t know.
Researcher: So how can circulation system get the blood sugar out for
use?
S212: Maybe our pulsation…right?
Concerning the explanation CHBS, there were two kinds of categorization from
students’ thoughts.
_1_Homeostasis means a “specific value”
Researcher: What is called homeostasis of blood sugar?
S004: Well…it always has a “specific value”.
Researcher: What do you mean by “specific value”?
S004: “Specific value” means a “fixed number”.
_2_Have an idea of standard
Researcher: What is called homeostasis of blood sugar?
S212: Homeostasis of blood sugar should mean there is a target…..like
a standard…when over the standard people will get diabetic
3
disease………should have that standard……too high or too low
standard.
Conclusion
From other researchers’ studies, we understand how important and difficult the
concept of homeostasis is (Barrass, 1984; Simpson & Marek, 1988; Westbrook &
Marek, 1992). However, we discovered most of students’ explanations for
homeostasis of blood sugar were related to life experiences and external behavior.
Otherwise, we found students got problems to present the micro phenomenon of
homeostasis of blood sugar, such as the function of insulin, glucagons, and the
regulation of blood sugar. The difficulties of learning the micro phenomenon have
been revealed in many studies as well, especially the concepts regarding chemistry
and physics (Banerjee, 1991; Cotignola, Bordogna, Punte, & Cappannini, 2002;
Lubben, Netshisaulu, & Campbell, 1999; Nicoll, 2001). As mentioned before,
homeostasis of blood sugar is an integrated and comprehensive topic in biology,
which includes systems, homeostasis and models (Penner, 2000). To improve teaching
comprehensive knowledge, Modell had brought the principles in his article “How to
help students understand physiology?” (Modell, 2000). Except memorization, he
mentioned the importance of the general model when teachers help students to learn
physiology. Although students could learn fast via context model, students usually
have problems in transferring knowledge to other fields. Therefore, teachers should
assist students to grasp the general models from context model. One example of
context model is Fick equation that was originally described in heart-vessel system
and mass balance concept, and the same principle could be conducted to both of the
composing of gas when we exhale, and the gas of alveolus. However students usually
recognize these subjects as three different situations, and then use different models to
deal with the information. In fact, these subjects show the same general model.
According to this kind of results, students could not apply the implicit principles to
other situations, and also could not solve problems effectively (Modell, 2000). In sum,
although authentic learning has been promoted of late(Cumming & Maxwell, 1999;
Wiggins, 1993; Wolf, Bixby, Glenn, & Gardner, 1991), as science educators, we
should help students to grasp the general models from life experience as well.
References
Banerjee, A. C. (1991). Misconceptions of Students and Teachers in Chemical
Equilibrium. International Journal of Science Education, 13(4), 487-494.
Barrass, R. (1984). Some misconceptions and misunderstandings perpetuated by
teachers and textbooks of biology. Journal of Biological education, 18(3),
201-206.
Chi, M. H., Leeuw, N., Chiu, M. H., & Lavancher, C. (1994). Eliciting selfexplainations improves understanding. Cognitive Science, 18, 439-477.
Cotignola, M. I., Bordogna, C., Punte, G., & Cappannini, O. M. (2002). Difficulties in
Learning Thermodynamic Concepts: Are They Linked to the Historical
Development of This Field? Science and Education, 11(3), 279-291.
Cumming, J. J., & Maxwell, G. S. (1999). Contextualising authentic assessment.
Assessment in Education, 6(2), 177-194.
Fred, N. F., James, S., & William, L. (1982). Teachers' perceptions of improtant and
4
difficult science content. Science Education, 66(4), 531-538.
Horton, P. B. (1993). An Investigation of the Effectiveness of Concept Mapping as an
Instructional Tool. Science Education, 77(1), 95-111.
Kinchin, I. M. (2000). Concept-Mapping Activities To Help Students Understand
Photosynthesis--and Teachers Understand Students. School Science Review,
82(299), 11-14.
Lubben, F., Netshisaulu, T., & Campbell, B. (1999). Students' Use of Cultural
Metaphors and Their Scientific Understandings Related to Heating. Science
Education, 83(6), 761-774.
Markham, K. M., & Others. (1994). The Concept Map as a Research and Evaluation
Tool: Further Evidence of Validity. Journal of Research in Science Teaching,
31(1), 91-101.
Modell, I. H. (2000). How to help students understand physiology? Emphasize
general models. Advances in Physiology Education, 23(1), 101-107.
Nicoll, G. (2001). A Report of Undergraduates' Bonding Misconceptions.
International Journal of Science Education, 23(7), 707-730.
Novak, J. D. (1988). Learning science and science learning. Studies in Science
Education, 15, 55-76.
Okebukola, P. A. (1992). Concept mapping with a Cooperative Learning Flavor.
American Biology Teacher, 54(4), 218-221.
Penner, D. E. (2000). Explaining sustems:investigating middle school students'
understanding of emergent phenomena. Journal of Research in Science
Teaching, 37(8), 784-806.
Simpson, W. D., & Marek, E. A. (1988). Understanding and misconceptions of
biology conceptions helds by students attending small high school and
students attending large high schools. Journal of Research in Science
Teaching, 25(5), 361-374.
Soyibo, K. (1995). Using Concept Maps to Analyze Text book Presentations of
Respiration. American Biology Teacher, 57(6), 344-351.
Stewart, J., & Others. (1979). Concept Maps: A Tool for Use in Biology Teaching.
American Biology Teacher, 41(3), 171-175.
Westbrook, S. L., & Marek, E. A. (1992). A cross-age study of student understanding
of the concept of homeostasis. Journal of Research in Science Teaching, 29(1),
51-61.
Wiggins, G. P. (1993). Assessment: authenticity, context, and validity. Phi Delta
Kappan, 75, 201-214.
Wolf, D., Bixby, J., Glenn, J. I., & Gardner, H. (1991). To use their mind well:
Investigating new forms of student assessment. Review of research in
education, 17(31-73).
5