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Bio 100 Lecture 9
Autotrophs – Plantae -Plants, Protists-Algae, Monera (bacteria)-cyanobacteria
Photoautotrophs
Photosynthesis
Plants are autotrophs, which
Photosynthesis
An endergonic reaction takes place in chloroplasts.
Chlorophyll
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Bio 100 Lecture 9
Stomata
Overview of Photosynthesis:
• Two stages
1. The Light Reactions
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Bio 100 Lecture 9
2. The Calvin Cycle
Let’s start by examining light:
•Light
energy flows in waves
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Bio 100 Lecture 9
Plant pigments
We see the color of the wavelengths that are transmitted. For example,
chlorophyll transmits green wavelengths.
The pigments of photosynthesis:
• Chlorophyll a
•
Chlorophyll b
The Light Reactions:
•In
the light reactions, light energy is transformed into the chemical energy
of ATP and NADPH.
Summary of the Light Reactions…
H2O
½ O2 + 2 H+
Transferred to
Light Energy
The Calvin Cycle: From Figure 7.10
Convert NADP+ to NADPH
and Convert ADP to ATP
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Bio 100 Lecture 9
What happens to the sugars produced? (Fig. 7.12)
Study Questions
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6.
Define photosynthesis.
What are the stomata?
What are the 2 stages of photosynthesis?
Where does the light reaction occur? Calvin cycle?
What is the end product of the light reaction and the calvin cycle?
What wavelengths do chlorophyll a and b absorb?