TESTS Flashcards
(12 cards)
What is the purpose of the starch test?
To determine the presence of starch in a plant tissue
The test indicates whether photosynthesis has occurred in the plant.
What color indicates a positive result in the starch test?
Blue / black
This color change occurs when iodine solution is applied to starch.
What color indicates a negative result in the starch test?
Orange / brown
This color indicates the absence of starch when iodine is applied.
What is the role of boiling water in the starch test?
To kill tissue and break down the cell wall
This step makes the starch more accessible for testing.
What is used to remove chlorophyll from the plant tissue in the starch test?
Hot ethanol
This step helps in visualizing the color change by removing green pigments.
How long should the plant be treated with hot ethanol?
5-10 minutes
This duration ensures effective chlorophyll removal.
What is the purpose of rinsing the tissue with cold water after ethanol treatment?
To soften the tissue
This step prepares the tissue for the iodine solution.
What equipment is used during the starch test to observe color changes?
White tile
A white tile provides a contrasting background for better visibility of color changes.
What is the setup for testing the CO2 concentration in plants?
Plant in a bell jar with water in another jar
This setup allows for comparison of photosynthesis in different conditions.
What is the result for Plant A in the CO2 test?
Negative (Orange / brown)
This indicates that Plant A did not produce starch.
What is the result for Plant B in the CO2 test?
Positive (Blue / black)
This indicates that Plant B produced starch.
What happens when iodine is applied to a variegated leaf?
Green part turns blue / black; white area turns orange / brown
This demonstrates that starch is present only in the green areas where chlorophyll is located.
