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72. Photosynthesis involves the conversion of light energy into chemical energy and it usually involves chloroplasts. (Some prokaryotic cells are capable of carrying out photosynthesis.)
73. Sunlight is used in photosynthesis as the initial source of energy. Sunlight is composed of a range of wavelengths (colors).
74. Chlorophyll is the main pigment involved in the absorption of sunlight so that photosynthesis may occur.
75. Wavelengths of light that are not absorbed by plant pigments are reflected. There are accessory pigments that help chlorophyll in the absorption of different wavelengths of sunlight.
76. Red and blue wavelengths of light are absorbed by chlorophyll and contribute greatly to the process of photosynthesis.
77. Green wavelengths of light are not absorbed (they are reflected) and they do not contribute to the process of photosynthesis.
78. Light energy is used to produce ATP, and to split water molecules to form oxygen and hydrogen.
79. The oxygen is produced by photolysis (splitting of water) and is given off by plants into the environment.
80. The hydrogen and ATP produced by photosynthesis are used to fix carbon dioxide to make organic molecules, mainly glucose.
81. Photosynthesis occurs in two stages, light dependent and light independent.
82. The light dependent phase requires light, while the light independent phase requires the products of the light dependent phase.
83. The light dependent reactions produce ATP, hydrogen and oxygen (which is given off into the atmosphere).
84. The light independent reactions fix carbon dioxide to produce organic molecules such as glucose.
85. The rate of photosynthesis can be determined by measuring the production of oxygen or by measuring the uptake of carbon dioxide. The rate can also be determined by measuring the biomass increase of a plant.
86. Temperature increases the rate of photosynthesis, up until denaturation occurs.
87. Higher carbon dioxide levels will also increase the rate of photosynthesis up to a certain level.
88. Light intensity also has an effect on photosynthesis rate.
Complete the following.
103. What energy conversion occurs in photosynthesis?
104. Explain the composition of sunlight.
105. What is the main photosynthetic pigment that absorbs light?___________________
106. What color of light is not able to be absorbed by green plants?_________________
107. What colors of light are absorbed most by green plants?_______________________
108. What happens in photolysis?
109. What is the waste gas given off by photosynthesis?_________________
110. What is carbon fixation?
111. What atmospheric gas is essential for photosynthesis to occur?_________________
112. Name three ways one could measure the rate of photosynthesis.
113. Besides hydrogen from the photolysis of water, what other energy source is essential for carbon fixation?
114. Produce a graph showing the effect of temperature on the rate of photosynthesis. Annotate where denaturation would occur.
115. Produce a graph showing the effect of increasing light intensity on the rate of photosynthesis.
116. Produce a graph showing the effect of increasing carbon dioxide concentration on the rate of photosynthesis.
117. Photosynthesis is said to have two stages, what are they?
118. Write the general equation for photosynthesis.
119. Write the general equation for cell respiration.
120. Explain the products of the light dependent stage of photosynthesis.
121. Explain the product of the light independent stage of photosynthesis.
122. Draw action and absorption spectrum for photosynthetic pigments.