How Certain Inhibitors Affect Photosynthesis

Observation

The authors of this experiment, The Effects of some Inhibitors on the Rates of

Photosynthesis and Respiration by Chlorella, knew that the rates of photosynthesis and

respiration of many plants are affected by an adding chemicals. (Yaun and Daniels, 2000) The

authors in this experiment would like to know in which ways different inhibitors affect

photosynthesis and respiration distinctly.

Objectives

 How certain inhibitors affect photosynthesis

 How certain inhibitors affect respiration

Hypothesis

The hypothesis of this study is as follows; the addition of some substances have strong

reactions to certain characteristics of photosynthesis and respiration is specific and effective.

(Yaun and Daniels, 2000) The null hypothesis
(Yaun and Daniels, 2000)

Sometime after the addition of the chlorella the gas and liquid hit equilibrium. Each experiment

was at room temperature and used the same lamp. Microliters of the algae cells were put into the

culture. The normal rates of respiration in the dark and photosynthesis in the light for the

experiment were recorded. A small amount of the inhibitor was put in through a tube, and rates

of respiration and photosynthesis were recorded again. Calculations were written down and

recorded in a chart.

The independent variable in this experiment would be the different inhibitors, which

include, potassium cyanide, sodium azide, hydroxylamine hydrogen chloride, and dinitrophenol.

The dependent variable would be the chlorella. The control group would be potassium cyanide, a

common inhibitor in which the others are being compared to. The treatment group would be not

adding any inhibitors to the solution.

Results

The resulting effects of the inhibitors on photosynthesis and respiration are as

such; for potassium cyanide on respiration and photosynthesis was Respiration and is

stimulated at small amounts of potassium cyanide, and is only partially changed