Biology study guide - Photosynthesis and Cellular respiration
1. Photosynthesis
1.1 Overview and definition
Chloroplasts and light energy
Key reactants and products (CO₂, H₂O, O₂, glucose, ATP, NADPH)
1.2 Light-Dependent Reactions
• Photosystem II (PSII), photolysis, electron transport chain
• Proton gradient, ATP synthase, Photosystem I (PSI), NADPH formation
1.3 Calvin Cycle (Light-Independent Reactions)
• Carbon fixation (RuBisCo and RuBP)
• Reduction phase (G3P production)
• Regeneration of RuBP
1.4 Limiting Factors of Photosynthesis
• Light intensity
• Carbon dioxide concentration
• Temperature and enzyme activity
2. Cellular Respiration
2.1 Overview and definition
Reactants and products (glucose, O₂ → CO₂, H₂O, ATP)
2.2 Glycolysis
• Location: Cytoplasm
• Glucose → pyruvate, net ATP and NADH yield
2.3 Link Reaction
• Pyruvate → Acetyl-CoA + CO₂ + NADH
2.4 Krebs Cycle
• Acetyl-CoA + oxaloacetate → citrate
• CO₂ release, ATP, NADH, FADH₂ production
2.5 Electron Transport Chain & Oxidative Phosphorylation
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, 1. Photosynthesis
1. Overview of photosynthesis:
Definition:
Photosynthesis is the biochemical process by which cells synthesise organic molecules (e.g. glucose)
from inorganic molecules (CO2 and H2O) in the presence of sunlight. During photosynthesis, light
energy is used to synthesize (produce) glucose from carbon dioxide and water, releasing oxygen as
a byproduct. This process can only occur in certain organisms such as plants or some bacteria. In
plants, photosynthesis occurs within a specialized organelle called the chloroplast.
Main components of photosynthesis:
Light energy:
-The sun is the primary source of energy for photosynthesis
-Light is absorbed by pigments in the chloroplast, primarily chlorophyll
Chloroplasts:
-Site of photosynthesis in plant cells
-Contains the pigment chlorophyll, which captures light energy
Important components and products of photosynthesis:
Carbon dioxide (CO₂):
-Absorbed from the atmosphere through the stomata of leaves
-Used in the Calvin cycle to synthesize glucose
Water (H₂O):
-Absorbed from the soil through the roots
-Splits during the light-dependent reactions, releasing oxygen as a by-product
Glucose (C₆H₁₂O₆):
-Product of photosynthesis
-Serves as an energy source for the plant and other organisms
Oxygen (O₂):
-Byproduct of photosynthesis
-Released into the atmosphere during the splitting of water in the light-dependent reactions
ATP and NADPH:
-Energy molecules produced during the light-dependent reactions
-Provide energy and reduce power for the Calvin cycle in the light-independent reactions
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1. Photosynthesis
1.1 Overview and definition
Chloroplasts and light energy
Key reactants and products (CO₂, H₂O, O₂, glucose, ATP, NADPH)
1.2 Light-Dependent Reactions
• Photosystem II (PSII), photolysis, electron transport chain
• Proton gradient, ATP synthase, Photosystem I (PSI), NADPH formation
1.3 Calvin Cycle (Light-Independent Reactions)
• Carbon fixation (RuBisCo and RuBP)
• Reduction phase (G3P production)
• Regeneration of RuBP
1.4 Limiting Factors of Photosynthesis
• Light intensity
• Carbon dioxide concentration
• Temperature and enzyme activity
2. Cellular Respiration
2.1 Overview and definition
Reactants and products (glucose, O₂ → CO₂, H₂O, ATP)
2.2 Glycolysis
• Location: Cytoplasm
• Glucose → pyruvate, net ATP and NADH yield
2.3 Link Reaction
• Pyruvate → Acetyl-CoA + CO₂ + NADH
2.4 Krebs Cycle
• Acetyl-CoA + oxaloacetate → citrate
• CO₂ release, ATP, NADH, FADH₂ production
2.5 Electron Transport Chain & Oxidative Phosphorylation
1
, 1. Photosynthesis
1. Overview of photosynthesis:
Definition:
Photosynthesis is the biochemical process by which cells synthesise organic molecules (e.g. glucose)
from inorganic molecules (CO2 and H2O) in the presence of sunlight. During photosynthesis, light
energy is used to synthesize (produce) glucose from carbon dioxide and water, releasing oxygen as
a byproduct. This process can only occur in certain organisms such as plants or some bacteria. In
plants, photosynthesis occurs within a specialized organelle called the chloroplast.
Main components of photosynthesis:
Light energy:
-The sun is the primary source of energy for photosynthesis
-Light is absorbed by pigments in the chloroplast, primarily chlorophyll
Chloroplasts:
-Site of photosynthesis in plant cells
-Contains the pigment chlorophyll, which captures light energy
Important components and products of photosynthesis:
Carbon dioxide (CO₂):
-Absorbed from the atmosphere through the stomata of leaves
-Used in the Calvin cycle to synthesize glucose
Water (H₂O):
-Absorbed from the soil through the roots
-Splits during the light-dependent reactions, releasing oxygen as a by-product
Glucose (C₆H₁₂O₆):
-Product of photosynthesis
-Serves as an energy source for the plant and other organisms
Oxygen (O₂):
-Byproduct of photosynthesis
-Released into the atmosphere during the splitting of water in the light-dependent reactions
ATP and NADPH:
-Energy molecules produced during the light-dependent reactions
-Provide energy and reduce power for the Calvin cycle in the light-independent reactions
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