1. Student Understanding of Osmosis and Water Potential: A case study
Tor Siong Hoon Pahang Matriculation College

2. Objectives of Study
explore student learning difficulty in osmosis and water potential
identify level of student understanding in osmosis and water potential.

3. Significance of the Study
concept of water potential
gaseous exchange and control in plants
transport of water and minerals in plants.

4. Limitation of Study
93 life science students taught by 2 lecturers from biology tutorial classes
studying biology in the Bahasa Malaysia at secondary school level.
students in matriculation program for about two months
focused on osmosis and water potential

5. Research design Benjamin Bloom (1964)
three domains: cognitive, affective and psychomotor in educational activities
six major categories: starting from the simplest behavior to the most complex
Knowledge
Comprehension
Application
Analysis
Synthesis
Evaluation

6. Independent Variables
Research design
Independent Variables
Dependent Variable
Understanding
definitions of
terms
Explaining, illustrating
concepts & evaluation
Understanding Water Potential
Understanding
Water Potential
Application of concepts

7. Methodology of Study
quantitative and qualitative approaches of data collection.
quantitative data: diagnostic test
related to the learning water potential based on the guide of Bloom’s taxonomy
ranging from knowledge, comprehension, application, analysis, synthesis and evaluation.
quantitative method: self evaluation form based on the diagnostic test

8. Data Analysis
Reliability analysis for internal consistency using Cronbach alpha yielded a coefficient of 0.691
Factors
Number of items
Cronbach alpha
A: Definition 8
0.760
B: Explain 2
0.658
C: Illustrate &
Predict 12
0.666
D: Problem Solving 5
0.672

9. Findings SPM Results (%) A1 & A2 B3 & B4 C5 & C6 Biology 28.0% 60.2%
SPM Results (%)
Count
A1 & A2
B3 & B4
C5 & C6
Biology
28.0%
60.2%
10.8% 93
Chemistry
40.9%
48.4%
Physics
22.0%
49.3%
28.6% 91
Mathematics
98.8%
2.2%
1.1%
English
41.9%
49.5%
8.6%

10. Osmosis & isotonic solutions
Hypertonic and hypotonic solutions
Concentration gradient, water potential, solute potential,
and pressure potential

11. membrane is selectively permeable
membrane is selectively permeable to water and iodine

12. Figure 3
Figure 4

13. C: Illustrations of Concepts
Figure 4 (isotonic solutions) better understood compared to figure 3 (solutions of different concentrations)
Confusion probably arises as a result of the basic concept of osmosis not well understood.
consistent with the trend as in section A
more students could define isotonic solutions but lesser students could define hypertonic

14. D: Making evaluations Refer to figure 4, state whether: Correct Wrong
Not answered
Count &
Percentage i.
there is water movement between 2 isotonic solutions
70 (75.3%)
21 (22.6%)
2 (2.2%)
ii.
there is net water movement between 2 isotonic solutions
39 (41.9%)
43 (46.2%)
11 (11.8%)
iii.
there is net change in water concentration on either side of membrane
38 (40.9%)
.45 (48.4%)
10 (10.8%)

15. D: Making evaluations higher level of understanding
75.3% for 2 isotonic solutions.
41.9% for net water movement.
students seem to either guess or they do not really understand what happens to the water molecules in isotonic solution.

16. E: Problem Solving
The water potential of a plant cell (cell) can be calculated using the following equation.
cell = s + 
where s = solute potential
and p = pressure potential
A plant cell was immersed in pure water until it was fully turgid (shown in figure 5).
It was then placed in a concentrated solution until it was plasmolysed. The table shows some of the values of the potentials in the cell at equilibrium under these different conditions.
Figure 5
Condition of cell
Potential (kPa)
cell s p
fully turgid
(i)
(ii)
+350
plasmolysed
(iii)
-550
(iv)

17. E: Problem Solving
Cell when fully turgid, 61.3% of the students answered correctly
the skill involved is mechanical formula substitution.
Cell in a different condition (plasmolysed)
47.3% of the students answered correctly
skill involve demands understanding of solute potential, pressure potential to calculate water potential

18. Suggestions
Silverman (1987): student’s learning governed by student’s native ability and prior preparation.
also depends on learning style and instructor’s teaching style
Felder (2005): students have different levels of motivation and different responses to specific classroom environments and instructional practices
Woods et al. (2000): students who adopted a strategic approach of study are more organized and efficient in their study

19. Suggestions … contd
Yusminah et al. (2006) found that most of the Biology lecturers merely read the slides during lecture classes.
Suggestion in this study: Although not possible to discover everything that affects what a student learns in a class,
needful for the lecturers at Matriculation to explore and devise varied teaching strategies to induce students to adopt a deep approach to learning and promote students’ intellectual development

20. Conclusion
Basic concepts taught in their secondary schools not fully understood
Students could not master questions in higher learning levels because they have not mastered lower learning skills
parallel to the idea posed by in the Bloom’s Taxonomy
Students rely on rote memorization and mechanical formula substitution
make little or no effort to understand the material being taught.
Students have not really explored the limits of applicability of new material
only skiing through the concepts on water potential.

21. Greetings from Pahang Matriculation College
Thank you
Greetings from Pahang Matriculation College