What was the role of Bromothymol blue in the photosynthesis experiment with Elodea sp?

This lab involves the qualitative measurement of the changes in carbon dioxide concentration associated with respiration and photosynthesis in the freshwater plant Elodea. Bromthymol blue is used as an indicator for the presence of CO2 in solution.

What does Bromothymol blue indicate during photosynthesis?

Bromothymol blue solution, BTB, can indicate the presence of carbon dioxide in the water. When little or no carbon dioxide is present, BTB will show a blue color. Yellow indicates more carbon dioxide. Problem: To observe evidence of photosynthesis in a water plant.

How do you preserve Elodea?

Elodea arrives in a sealed plastic bag. Upon arrival, this should be opened and Elodea should be kept moist, or it should be placed in a habitat. For short term storage (1–2 weeks), Elodea should be placed in its bag into the refriger- ator (4 °C). Regardless of its housing, do not allow your Elodea to dry out.

What will happen if the Elodea plant is left in the dark?

Oxygen is a by-product of photosynthesis. The Elodea vial placed in the dark lacked light, so photosynthesis did not occur and DO levels would expect to decrease as respiration occurs.

What is the purpose of the bromothymol blue BTB solution?

The main uses of bromothymol blue are for testing pH and for testing photosynthesis and respiration. Bromothymol blue has a blue color when in basic conditions (pH over 7), a green color in neutral conditions (pH of 7), and a yellow color in acidic conditions (pH under 7).

What is the reason for the color change in the test tube with Elodea submerged in BTB solution?

When a person exhales, carbon dioxide is released. Bromothymol blue solution, BTB, can indicate the presence of carbon dioxide in the water. When little or no carbon dioxide is present, BTB will show a blue color. Depending upon the amount of carbon dioxide, BTB will change to green or yellow.

Why is Elodea important for lake ecosystems?

Ecological Importance. Elodea provides habitat for many small aquatic animals, which fish and wildlife eat. Geese, ducks, and swans are particularly attracted to this plant. Elodea is an excellent oxygen producer and frequently used by fish to protect fry.

What is the purpose of bromothymol blue in this experiment?

Bromthymol Blue is a dye used as an indicator in determining pH. Bromthymol blue is a weak acid. It can be in acid or base form, depending on the pH of the solution. This reagent is yellow in acidic solutions, blue in basic solutions and green in neutral solution.

Does elodea densa spread?

Propagation of Elodea Pondweed Male plants are rare, though, so these plants usually propagate asexually by stems breaking off and rooting. Once this waterweed finds its way into wild areas, it can and does become invasive.

Does elodea produce oxygen?

The cellular structure of the elodea plant makes it an ideal candidate for oxygen experiments. As photosynthesis occurs, elodea plants pass the produced oxygen from leaves to stem.

What happens when you exhaled into the Bromothymol solution?

Carbon dioxide production can be measured by breathing through a straw into a solution of bromothymol blue (BTB). BTB is an acid indicator; when it reacts with acid it turns from blue to yellow. The more carbon dioxide you breathe into the BTB solution, the faster it will change color to yellow.

Why does the Elodea plant produce bromothymol blue?

Elodea plant, the chemical . Bromothymol Blue (which acts as an indicator to show if photosynthesis is occurring). Bromothymol blue works because it is able to detect the presence of . CO2 (needed for photosynthesis) and . O2 (released during photosynthesis) in solution. In a test tube, you will see that: bromothymol blue + CO2 = green color

How is cyclosis performed on an Elodea leaf?

One leaf was taken from an Elodea plant and examined under a light microscope at a magnification of around 400x. A cell was then located which performed cyclosis, and was exposed to the light produced by 1 lamp. 5 recordings were taken of the time taken for one chloroplast to move from one end of the cell to the other.

How to make bromothymol blue in photosynthesis lab?

Pour 25 mL of the bromothymol blue + water solution into each of the three test tubes. Cover Tube 1 with tin foil (there is no Elodea in Tube 1) and place it in the test tube rack Add a 7 cm piece of Elodea to Tube 2. Using your straw, GENTLY push the Elodea to the bottom of the test tube.

How do you put an Elodea in a test tube?

Using your straw, GENTLY push the Elodea to the bottom of the test tube. Cover the test tube with plastic wrap or a stopper. Then place it in the test tube rack.