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Table Nr 1. Color changes in IKI test for presence of starch and for presence of sugar in Benedict’s test Part 1 |Original content |Original color |Final color |Color after Benedict’s test | |Sausage casing |glucose and starch |clear |clear | | |Beaker |distiled water |transparent |transparent | | |Beaker + IKI |distilled water and IKI |light yellow |light yellow | | |Part 2 | | | | | |Cuvette C |distilled water |transparent |blue |blue | |Cuvette S |glucose and starch |clear |blue |yellow/ orange | |Cuvette B |distilled water and IKI | light yellow |blue |light yellow | |Cuvette SI |glucose, starch and IKI |yellow |purple | | The solution inside the sausage casing containing glucose and starch was transparent (clear) in the beginning of the experiment. After 30 min of incubation time the solution inside sausage casing was still transparent (clear). In IKI test, the content of sausage casing has changed color from yellow to dark purple (cuvette SI), in Benedict’s test the solution from the sausage casing changed color form clear to blue after addition of Benedict’s reagent (cuvette S), after heating solution in water bath (60??C), the content of cuvette S has changed color to yellow/orange.
The original content in the beaker was distilled water which was transparent. After incubation time and addition of 1ml of IKI the color of water changed to light yellow. The solution from the beaker was transferred to cuvette B and after adding 5 drops of Benedict’s reagent the solution turned blue. Next, after cuvette B was heated in water bath its solution changed color from blue to yellow. The cuvette C was a control sample, original content (distilled water) was transparent (clear). After adding Benedict’s reagent and heating it turned blue. Table nr 2. Percent weight changes for potato cubes soaked in different sucrose solution. Weight changes for different size of potato cubes. Group data. Lab group |Percent weight |Percent weight |Percent weight |Percent weight |Percent weight |Percent weight | | |change (%) for 0 M |change (%) for 0. 2 |change (%) for 0. 4 |change (%) for 0. 6 |change (%) |change (%) | | |sucrose |M sucrose |M sucrose |M sucrose |For small potato |For large potato | |Group 1 |16. 4 |8. 7 |-2. 9 |-7. 9 |7. 7 |10. 3 | |Group 3 |17. 4 |10. 2 |-6. 5 |-11. 9 |-14. |-7. 2 | |Group 4 |12. 6 |8. 2 |-2. 9 |-5. 2 |13. 6 |9. 6 | |Group 5 |14. 7 |12. 9 |5. 7 |6. 3 |7. 3 |17. 0 | |Group 6 |8. 6 |6. 6 |0 |-2. 9 |13. 2 |5. 8 | |Group 7 |9. 8 |6. 9 |3. 5 |6. 5 |14. 9 |9. 2 | |Group 8 |15. |4. 5 |3. 9 |3. 4 |21. 4 |7. 9 | |Group 9 |15. 0 |13. 0 |-0. 7 |-4. 0 |22. 0 |8. 0 | |Group 10 |16. 6 |13. 6 |-0. 4 |-8. 3 |16 |8. 9 | |Mean |13. 81 |9. 06 |0. 87 |-2. 10 |12. 18 |7. 75 | |SD |2. 96 |3. 23 |4. 63 |6. 2 |10. 61 |6. 02 | |SE |0. 94 |1. 02 |1. 47 |2. 06 |3. 35 |1. 90 | According to the mean group data values (Table nr 2), it can be observed that the highest percent weight change, 13. 81 was for 0 M sucrose solution. The smallest value was obtained for 0. 6 M sucrose solution which was -2. 10. However, it can be noticed that there is big discrepancy between values (sucrose concentration 0. 4 M and 0. 6 M) for each group. Standard errors for these two concentration are high, respectively 1. 47 and 2. 06 Table Nr 3.
Values of surface, volume and surface to volume ratio for small and large potato cubes | |Dimensions (cm) |Surface area (cm2) |Volume (cm3) |Surface to volume ratio | |Small potato cube |1 x 1 x 1 |6 |1 |6:1 | |Large potato cube |2 x 2 x 2 |24 |8 |3:1 | According to mean group values for percent weight change for small and large potato cube (Table nr 2) and calculated values of surface to volume ratio (Table nr 3) we observed that for greater surface to volume ratio percent weight change was bigger than for smaller surface to volume ratio. The small potato cube which had 6:1 the surface to volume ratio changed its weight by 12. 18% and larger potato cube with 3:1 ratio changed its weight by 7. 75%. Figure nr 4. Percent weight change based on sucrose concentration The above graph presents decreasing trend in percent weight change in different sucrose solutions.
As the concentration of sucrose increases the percent weight change is getting smaller. For 0. 5 M sucrose concentration the percent weight change was 0. The observed onion cell in 0. 9% NaCl solution (Figure Nr 1) was rectangular and surrounded by cell wall. The cell was filled with pink central vacuole, the size of the cell was 308 ? m. The onion epidermal pill cell placed in unknown solution A ( Figure Nr 2) had size of 280 ? m. Central vacuole was separated from the cell wall and had irregular shape. The onion epidermal pill cell immersed in unknown solution B had central, pink vacuole filling the whole cell. The size of onion cell was 420 ? m. The nucleus was seen close to the cell wall.