Are chloroplasts necessary for reduction of DCPIP?
In this investigation, DCPIP (2,6-dichlorophenol-indophenol), a blue dye, acts as an electron acceptor and becomes colourless when reduced, allowing any reducing agent produced by the chloroplasts to be detected….Using a micro-centrifuge.
| Time/min | Absorption Tube 1 | Absorption Tube 5 |
|---|---|---|
| 8 | 0.6 | 1.6 |
| 9 | 0.6 | 1.3 |
| 10 | 0.6 | 1.1 |
Where in the chloroplast does the Hill reaction occur?
granum part
Hill’s reaction or Light reaction: It occurs in presence of light in granum part of chloroplast. 2. Dark reaction or Blackmann’s reaction: It does not require light directly, occuring irrespective of presence or absence of light. However, it is dependent upon the end products of light reaction.
What are the reactants of the Hill reaction?
Carbon dioxide, water, chlorophyll, and light energy are the reactants. � Water, atmospheric oxygen (which we breathe) and carbohydrates (which we eat) are formed.
What chemical reaction is performed by chloroplasts?
Photosynthesis occurs in the chloroplast, an organelle specific to plant cells. The light reactions of photosynthesis occur in the thylakoid membranes of the chloroplast. Electron carrier molecules are arranged in electron transport chains that produce ATP and NADPH, which temporarily store chemical energy.
Why does DCPIP Decolourise more slowly in the presence of ammonium hydroxide?
electrons takes place. DCPIP is decolourised more slowly when ammonium hydroxide is added. Ammonium hydroxide has slowed electron transfer along electron transport chain to DCPIP. Ammonium hydroxide accepts electrons and does not pass electrons along electron transport chain to DCPIP.
How does temperature affect the Hill reaction?
Hill reaction rates, measured by O(2) evolution or by ferricyanide reduction, increase with increasing temperature to approximately 40 C. The temperature optimum of NADP reduction is 42 C while the optimum for noncyclic photophosphorylation is 35 C.
Which of the following is not required for Hill Reaction?
The correct answer would be D, Carbon dioxide. Explanation: Carbon dioxide is not required for Hill Reaction.
What function do chloroplasts?
photosynthetic
Chloroplasts are plant cell organelles that convert light energy into relatively stable chemical energy via the photosynthetic process. By doing so, they sustain life on Earth. Chloroplasts also provide diverse metabolic activities for plant cells, including the synthesis of fatty acids, membrane lipids.
Why is DCPIP a good indicator?
DCPIP. Using DCPIP to determine the concentration of ascorbic acid or Vitamin C in a solution. DCPIP is commonly used as an indicator for Vitamin C. If vitamin C, which is a good reducing agent is present , the blue dye, which turns pink in acid conditions and is reduced to a colourless compound by ascorbic acid.
When does DCPIP take place in the Hill reaction?
DCPIP takes the place of NADP in this set-up. NADP is usually reduced in the light-dependent reaction as electrons are excited from the photosystems and passed along an electron transport chain.
How are chloroplasts used in the Hill reaction?
To investigate photosynthesis using isolated chloroplasts (the Hill reaction). Amount of DCPIP reduced (can be judged based on the colour of the mixture) Use chloroplasts from the same species of plant – chopped spinach leaves can be used Amount of chloroplast/buffer solution added to each tube – 5cm³ to each tube
What happens to DCPIP when it is oxidized?
42 DCPIP (2,6-dichlorophenol indophenol) is a dye able to accept electrons from a variety of donors. When DCPIP is oxidized, it is blue. Reduced DCPIP is colorless. The reduction of DCPIP by electrons derived from H2O coupled with the production of O2 is known as the Hill Reaction.
What did Robert Hill do with DCPIP in 1937?
In 1937 Robert Hill showed that this partial reaction of the electron transport chain using DCPIP could be used to investigate the rate of oxygen evolution (from the splitting of water molecules in PSII) and thus the rate of photosynthesis in thylakoids of isolated chloroplasts.