4.2.1
Respiration
Energy
Energy
Organisms need energy for many reasons:
![Illustrative background for Growth](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/building-2739204_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Growth ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/building-2739204_640-min,h_400,q_80,w_640.jpg)
Growth
Growth
- To make larger molecules from smaller molecules. For example:
- Glucose molecules can be joined together to produce starch (in plants).
- Proteins can be made from amino acids in plants and animals.
![Illustrative background for Contraction](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/cheetah-2859581_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Contraction ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/cheetah-2859581_640-min,h_400,q_80,w_640.jpg)
Contraction
Contraction
- To contract the muscles of animals, allowing them to move.
![Illustrative background for Homeostasis](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.1.4/thermometer-1614708_640-min,h_400,q_80,w_640.png)
![Illustrative background for Homeostasis ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.1.4/thermometer-1614708_640-min,h_400,q_80,w_640.png)
Homeostasis
Homeostasis
- To keep the body temperature of warm-blooded animals (mammals and birds) relatively constant.
Respiration
Respiration
Respiration is an exothermic reaction (releases energy) that supplies all the energy needed by living organisms. This reaction happens continuously in all living cells. The reaction can be aerobic (with oxygen) or anaerobic (without oxygen).
![Illustrative background for Aerobic respiration (with oxygen)](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/sky-1441936_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Aerobic respiration (with oxygen) ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/sky-1441936_640-min,h_400,q_80,w_640.jpg)
Aerobic respiration (with oxygen)
Aerobic respiration (with oxygen)
- In aerobic respiration, glucose reacts with oxygen in the mitochondria of cells to give carbon dioxide, water and energy.
- Glucose + oxygen → carbon dioxide + water (+ energy)
- C6H12O6 + 6O2 → 6CO2 + 6H2O (+ energy)
![Illustrative background for Anaerobic respiration in animals](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/relay-race-655353_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Anaerobic respiration in animals ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/relay-race-655353_640-min,h_400,q_80,w_640.jpg)
Anaerobic respiration in animals
Anaerobic respiration in animals
- Glucose is not broken down completely, making it a less efficient way of transferring energy than aerobic respiration.
- In animals, glucose is converted to lactic acid:
- Glucose → lactic acid
- Anaerobic respiration happens when insufficient (not enough) oxygen reaches the muscles during periods of intense activity.
![Illustrative background for Anaerobic respiration in plants](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/beer-2449887_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Anaerobic respiration in plants ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/beer-2449887_640-min,h_400,q_80,w_640.jpg)
Anaerobic respiration in plants
Anaerobic respiration in plants
- In plant and yeast cells, glucose is converted into ethanol and carbon dioxide.
- Glucose → ethanol + carbon dioxide
- In yeast cells, this is called fermentation. This is an important step in the manufacture (making) of both bread and alcohol.
Metabolism
Metabolism
Metabolism refers to all the chemical reactions that happen in an organism. Many of these chemical reactions create new molecules with the help of enzymes. Metabolic reactions include:
![Illustrative background for Converting glucose](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.2%20Osmosis/sugar-258113_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Converting glucose ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/1.3.2%20Osmosis/sugar-258113_640-min,h_400,q_80,w_640.jpg)
Converting glucose
Converting glucose
- Converting glucose into starch (plants), glycogen (animals) and cellulose (plants).
![Illustrative background for Making lipids](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/lips-1690875_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Making lipids ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/lips-1690875_640-min,h_400,q_80,w_640.jpg)
Making lipids
Making lipids
- Combining glycerol and fatty acid chains to make lipid molecules.
![Illustrative background for Making amino acids](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.1.1%20Photosynthesis/bodybuilder-331670_640%20-%20Edited-min,h_400,q_80,w_640.jpg)
![Illustrative background for Making amino acids ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.1.1%20Photosynthesis/bodybuilder-331670_640%20-%20Edited-min,h_400,q_80,w_640.jpg)
Making amino acids
Making amino acids
Combining glucose and nitrate ions to make amino acids. Amino acids can then be combined to make proteins.
![Illustrative background for Breaking down excess proteins](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/4.2.1-%20Respiration/crash-1082857_640-min,h_400,q_80,w_640.jpg)
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Breaking down excess proteins
Breaking down excess proteins
- Breaking down excess proteins to form urea, which is excreted (got rid of) in urine.
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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