4.1.1
Photosynthesis
Photosynthesis
Photosynthesis
Photosynthesis takes place inside chloroplasts found in plants and algae. The reaction is endothermic, meaning that it requires energy. The source of this energy is sunlight, which is trapped by a chemical called chlorophyll inside chloroplasts in plant cells.
The Rate of Photosynthesis
The Rate of Photosynthesis
The four key factors affecting the rate of photosynthesis are:
![Illustrative background for Temperature](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.1%20Diffusion%20and%20active%20transport/thermometer-1614708_640-min%20-%20Edited-min,h_400,q_80,w_640.png)
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Temperature
Temperature
- Increasing the temperature increases the rate of photosynthesis because more energy is provided.
- But, if the temperature is increased to above about 45°C, the enzymes that catalyse (speed-up) the reaction begin to denature (not work anymore).
- This causes the rate of the reaction to drop sharply until it stops altogether.
![Illustrative background for Light intensity](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.1.1%20Photosynthesis/forest-2178187_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Light intensity ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.1.1%20Photosynthesis/forest-2178187_640-min,h_400,q_80,w_640.jpg)
Light intensity
Light intensity
- A greater light intensity means a greater rate of photosynthesis. This is because more energy is being provided.
- But, if the light intensity is increased above a certain threshold, the rate of photosynthesis will not increase because another factor (such as temperature) is limiting the rate of the reaction.
![Illustrative background for Carbon dioxide concentration](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.1.1%20Photosynthesis/car-exhaust-1902909_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Carbon dioxide concentration ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.1.1%20Photosynthesis/car-exhaust-1902909_640-min,h_400,q_80,w_640.jpg)
Carbon dioxide concentration
Carbon dioxide concentration
- Increasing the carbon dioxide concentration increases the rate of photosynthesis because carbon dioxide is a reactant in photosynthesis.
- But, above a certain threshold, further increases in the carbon dioxide concentration do not increase the rate of photosynthesis because another factor (such as light intensity) is limiting the rate of reaction.
![Illustrative background for Chlorophyll concentration](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/3.3.1%20-%20magnesium%20deficient%20plant,h_400,q_80,w_640.jpg)
![Illustrative background for Chlorophyll concentration ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/3.3.1%20-%20magnesium%20deficient%20plant,h_400,q_80,w_640.jpg)
Chlorophyll concentration
Chlorophyll concentration
- High chlorophyll concentration gives a high rate of photosynthesis.
1Cell Biology
1.1What's in Cells?
1.1.1Types of Cells
1.1.2Properties of Prokaryotes
1.1.3Standard Form
1.1.4Standard Form - Calculations
1.1.5Addition in Standard Form - Calculations
1.1.6Subtraction in Standard Form - Calculations
1.1.7Multiplication in Standard Form - Calculations
1.1.8Division in Standard Form - Calculations
1.1.9Animal Cells
1.1.10Plant Cells
1.1.11Differences Between Animal & Plant Cells
1.1.12Bacterial Cells
1.1.13Types of Cells HyperLearning
1.1.14Cell Specialisation in Animals
1.1.15Sperm Cells
1.1.16Nerve Cells
1.1.17Muscle Cells
1.1.18Cell Specialisation in Plants
1.1.19Microscopy
1.1.20Developments in Microscopy
1.1.21Microscope Practical
1.1.22Microscopy - Calculations
1.1.23Culturing Microorganisms
1.1.24Contamination
1.1.25Avoiding Contamination
1.1.26Calculating Bacteria
1.1.27Calculating Bacteria - Calculations
1.1.28End of Topic Test - What's in Cells?
1.1.29Exam-Style Questions - Cell Structure & Microscopy
1.2Cell Division
1.3Transport in Cells
1.3.1Diffusion
1.3.2Factors Affecting Diffusion
1.3.3Surface Area : Volume
1.3.4Surface Area : Volume - Calculations
1.3.5Exchange Surfaces
1.3.6Examples of Exchange Surfaces
1.3.7Osmosis
1.3.8Osmosis Practical
1.3.9Active Transport
1.3.10Transport in Cells
1.3.11End of Topic Test - Cell Division & Transport
1.3.12Grade 9 - Cell Transport
2Organisation
2.1Principles of Organisation
2.2Enzymes
2.2.1Enzymes
2.2.2Enzymes HyperFlashcards
2.2.3Rate of Reaction
2.2.4Calculating Rate of Reaction
2.2.5Rate of Reaction - Calculations
2.2.6Digestion
2.2.7Bile
2.2.8Examples of Digestive Enzymes - Amylase
2.2.9Examples of Digestive Enzymes - Protease
2.2.10Examples of Digestive Enzymes - Lipase
2.2.11Testing for Biological Molecules
2.2.12End of Topic Test - Organisation & Enzymes
2.2.13Grade 9 - Enzymes
2.2.14Exam-Style Questions - Enzymes
2.3Circulatory System
2.3.1Types of Blood Vessel
2.3.2Blood Vessels - Arteries
2.3.3Blood Vessels - Capillaries
2.3.4Blood Vessels - Veins
2.3.5The Heart - Structure
2.3.6The Heart - Function
2.3.7Important Blood Vessels
2.3.8Double Circulatory System
2.3.9Gas Exchange
2.3.10Gas exchange - Calculations
2.3.11Alveoli
2.3.12Blood Components
2.3.13Platelets
2.3.14Red Blood Cells
2.3.15White Blood Cells
2.3.16End of Topic Test - Circulatory System
2.4Non-Communicable Diseases
2.4.1Health Issues
2.4.2Disease Interactions
2.4.3Sampling
2.4.4Sampling - Calculations
2.4.5Risk Factors
2.4.6Examples of Risk Factors
2.4.7Risk Factor Graphs
2.4.8Coronary Heart Disease
2.4.9Heart Valve Disease
2.4.10Heart Failure
2.4.11Treating Heart Disease
2.4.12Cancer
2.4.13Cancer Risk Factors
2.4.14End of Topic Test - Non-Communicable Diseases
2.4.15Exam-Style Questions - Coronary Heart Disease
2.5Plant Tissues, Organs & Systems
3Infection & Response
3.1Communicable Disease
3.1.1Spreading Disease
3.1.2Viruses
3.1.3Other Pathogens
3.1.4Human Defence Systems
3.1.5Human Defence Systems 2
3.1.6Grade 9 - Immune System
3.1.7Antibiotics
3.1.8Drug Development
3.1.9Drug Testing
3.1.10Drug Testing / Efficacy - Calculations
3.1.11End of Topic Test - Communicable Diseases
3.1.12Exam-Style Questions - Microorganisms & Disease
3.2Monoclonal Antibodies
4Bioenergetics
4.1Photosynthesis
5Homeostasis & Response
5.1Homeostasis
5.2The Human Nervous System
5.2.1The Nervous System
5.2.2The Nervous System HyperFlashcards
5.2.3Synapses
5.2.4Reflexes
5.2.5Exam-Style Questions - Nervous System
5.2.6The Brain
5.2.7Eye Anatomy
5.2.8Eye Function
5.2.9Control of Body Temperature
5.2.10Warming Up & Cooling Down
5.2.11Body Temperature HyperLearning
5.2.12End of Topic Test - Human Nervous System
5.3Hormonal Coordination in Humans
5.3.1Endocrine System
5.3.2Thyroxine & Adrenaline
5.3.3Blood Glucose
5.3.4Diabetes
5.3.5Control of Water Balance
5.3.6Urine
5.3.7Dialysis
5.3.8Transplants
5.3.9Puberty
5.3.10Menstruation
5.3.11Contraception
5.3.12Contraception 2
5.3.13Hormones for Infertility
5.3.14End of Topic Test - Homeostasis & Hormones
5.3.15Grade 9 - Hormonal Coordination
5.3.16Exam-Style Questions - Hormones & Contraception
6Inheritance, Variation & Evolution
6.1Reproduction
6.1.1Reproduction
6.1.2Reproduction 2
6.1.3Genome
6.1.4DNA
6.1.5Protein Synthesis
6.1.6Genetic Inheritance
6.1.7Genetic Crosses
6.1.8Inherited Disorders
6.1.9Inherited Disorders 2
6.1.10Genetic Crosses - Calculations
6.1.11Genome Screening & Sex Determination
6.1.12End of Topic Test - Reproduction
6.1.13Exam-Style Questions - DNA & Genetics
6.2Variation & Evolution
6.3Genetics & Evolution
7Ecology
7.1Adaptations & Interdependence
7.2Organisation of Ecosystems
7.3Biodiversity
7.4Trophic Levels
Jump to other topics
1Cell Biology
1.1What's in Cells?
1.1.1Types of Cells
1.1.2Properties of Prokaryotes
1.1.3Standard Form
1.1.4Standard Form - Calculations
1.1.5Addition in Standard Form - Calculations
1.1.6Subtraction in Standard Form - Calculations
1.1.7Multiplication in Standard Form - Calculations
1.1.8Division in Standard Form - Calculations
1.1.9Animal Cells
1.1.10Plant Cells
1.1.11Differences Between Animal & Plant Cells
1.1.12Bacterial Cells
1.1.13Types of Cells HyperLearning
1.1.14Cell Specialisation in Animals
1.1.15Sperm Cells
1.1.16Nerve Cells
1.1.17Muscle Cells
1.1.18Cell Specialisation in Plants
1.1.19Microscopy
1.1.20Developments in Microscopy
1.1.21Microscope Practical
1.1.22Microscopy - Calculations
1.1.23Culturing Microorganisms
1.1.24Contamination
1.1.25Avoiding Contamination
1.1.26Calculating Bacteria
1.1.27Calculating Bacteria - Calculations
1.1.28End of Topic Test - What's in Cells?
1.1.29Exam-Style Questions - Cell Structure & Microscopy
1.2Cell Division
1.3Transport in Cells
1.3.1Diffusion
1.3.2Factors Affecting Diffusion
1.3.3Surface Area : Volume
1.3.4Surface Area : Volume - Calculations
1.3.5Exchange Surfaces
1.3.6Examples of Exchange Surfaces
1.3.7Osmosis
1.3.8Osmosis Practical
1.3.9Active Transport
1.3.10Transport in Cells
1.3.11End of Topic Test - Cell Division & Transport
1.3.12Grade 9 - Cell Transport
2Organisation
2.1Principles of Organisation
2.2Enzymes
2.2.1Enzymes
2.2.2Enzymes HyperFlashcards
2.2.3Rate of Reaction
2.2.4Calculating Rate of Reaction
2.2.5Rate of Reaction - Calculations
2.2.6Digestion
2.2.7Bile
2.2.8Examples of Digestive Enzymes - Amylase
2.2.9Examples of Digestive Enzymes - Protease
2.2.10Examples of Digestive Enzymes - Lipase
2.2.11Testing for Biological Molecules
2.2.12End of Topic Test - Organisation & Enzymes
2.2.13Grade 9 - Enzymes
2.2.14Exam-Style Questions - Enzymes
2.3Circulatory System
2.3.1Types of Blood Vessel
2.3.2Blood Vessels - Arteries
2.3.3Blood Vessels - Capillaries
2.3.4Blood Vessels - Veins
2.3.5The Heart - Structure
2.3.6The Heart - Function
2.3.7Important Blood Vessels
2.3.8Double Circulatory System
2.3.9Gas Exchange
2.3.10Gas exchange - Calculations
2.3.11Alveoli
2.3.12Blood Components
2.3.13Platelets
2.3.14Red Blood Cells
2.3.15White Blood Cells
2.3.16End of Topic Test - Circulatory System
2.4Non-Communicable Diseases
2.4.1Health Issues
2.4.2Disease Interactions
2.4.3Sampling
2.4.4Sampling - Calculations
2.4.5Risk Factors
2.4.6Examples of Risk Factors
2.4.7Risk Factor Graphs
2.4.8Coronary Heart Disease
2.4.9Heart Valve Disease
2.4.10Heart Failure
2.4.11Treating Heart Disease
2.4.12Cancer
2.4.13Cancer Risk Factors
2.4.14End of Topic Test - Non-Communicable Diseases
2.4.15Exam-Style Questions - Coronary Heart Disease
2.5Plant Tissues, Organs & Systems
3Infection & Response
3.1Communicable Disease
3.1.1Spreading Disease
3.1.2Viruses
3.1.3Other Pathogens
3.1.4Human Defence Systems
3.1.5Human Defence Systems 2
3.1.6Grade 9 - Immune System
3.1.7Antibiotics
3.1.8Drug Development
3.1.9Drug Testing
3.1.10Drug Testing / Efficacy - Calculations
3.1.11End of Topic Test - Communicable Diseases
3.1.12Exam-Style Questions - Microorganisms & Disease
3.2Monoclonal Antibodies
4Bioenergetics
4.1Photosynthesis
5Homeostasis & Response
5.1Homeostasis
5.2The Human Nervous System
5.2.1The Nervous System
5.2.2The Nervous System HyperFlashcards
5.2.3Synapses
5.2.4Reflexes
5.2.5Exam-Style Questions - Nervous System
5.2.6The Brain
5.2.7Eye Anatomy
5.2.8Eye Function
5.2.9Control of Body Temperature
5.2.10Warming Up & Cooling Down
5.2.11Body Temperature HyperLearning
5.2.12End of Topic Test - Human Nervous System
5.3Hormonal Coordination in Humans
5.3.1Endocrine System
5.3.2Thyroxine & Adrenaline
5.3.3Blood Glucose
5.3.4Diabetes
5.3.5Control of Water Balance
5.3.6Urine
5.3.7Dialysis
5.3.8Transplants
5.3.9Puberty
5.3.10Menstruation
5.3.11Contraception
5.3.12Contraception 2
5.3.13Hormones for Infertility
5.3.14End of Topic Test - Homeostasis & Hormones
5.3.15Grade 9 - Hormonal Coordination
5.3.16Exam-Style Questions - Hormones & Contraception
6Inheritance, Variation & Evolution
6.1Reproduction
6.1.1Reproduction
6.1.2Reproduction 2
6.1.3Genome
6.1.4DNA
6.1.5Protein Synthesis
6.1.6Genetic Inheritance
6.1.7Genetic Crosses
6.1.8Inherited Disorders
6.1.9Inherited Disorders 2
6.1.10Genetic Crosses - Calculations
6.1.11Genome Screening & Sex Determination
6.1.12End of Topic Test - Reproduction
6.1.13Exam-Style Questions - DNA & Genetics
6.2Variation & Evolution
6.3Genetics & Evolution
7Ecology
7.1Adaptations & Interdependence
7.2Organisation of Ecosystems
7.3Biodiversity
7.4Trophic Levels
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