5.3.9
Water Balance
Water Balance
Water Balance
Water levels in the body must be kept relatively constant to control the amount of water and ions diffusing into and out of cells. Many factors can disrupt this balance.
Exhalation
Exhalation
- Water in the lungs leaves the body in the person’s breath.
Sweating
Sweating
- Water, ions and urea are all lost in sweat.
Eating too much salt
Eating too much salt
- This can make the blood ion concentration too high.
Illness
Illness
- Illnesses that cause fever, vomiting or diarrhoea can result in dehydration (the blood's water concentration is too low).
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 - Root Hair Cells
1.1.19Cell Specialisation in Plants - Xylem
1.1.20Cell Specialisation in Plants - Phloem
1.1.21Microscopy
1.1.22Magnification
1.1.23Developments in Microscopy
1.1.24Microscope Practical
1.1.25Microscopy - Calculations
1.1.26Culturing Microorganisms
1.1.27Contamination
1.1.28Avoiding Contamination
1.1.29Calculating Bacteria
1.1.30Calculating Bacteria - Calculations
1.1.31End of Topic Test - What's in Cells?
1.1.32Exam-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
1.3.8Required Practical - Osmosis
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
2.4.12Comparing Treatments of Heart Disease
2.4.13Cancer
2.4.14Cancer Risk Factors
2.4.15End of Topic Test - Non-Communicable Diseases
2.4.16Exam-Style Questions - Coronary Heart Disease
2.5Plant Tissues, Organs & Systems
2.5.1Plant Tissues
2.5.2Leaves
2.5.3Transpiration
2.5.4Rate of Transpiration
2.5.5Measuring Transpiration
2.5.6Translocation
2.5.7Transpiration Tissues - Xylem Cells
2.5.8Transpiration Tissues - Root Hair Cells
2.5.9Stomata
2.5.10Stages of Stomata
2.5.11Premium Knowledge - Transpiration
2.5.12End of Topic Test - Plants
2.5.13Exam-Style Questions - Plant Tissues
3Infection & Response
3.1Communicable Disease
3.1.1Spreading Disease
3.1.2Causing Diseases
3.1.3Preventing Infection
3.1.4Viruses
3.1.5Examples of Viruses
3.1.6Bacteria
3.1.7Fungi
3.1.8Protists
3.1.9Human Defence Systems - Non-Specific Defences
3.1.10Human Defence Systems - Immune Systems
3.1.11Antibodies
3.1.12Vaccinations
3.1.13Grade 9 - Immune System
3.1.14Antibiotics
3.1.15Antibiotic Resistance
3.1.16Drug Discovery
3.1.17Developing New Drugs
3.1.18Drug Testing
3.1.19Drug Testing in Laboratories
3.1.20Double-Blind Trials
3.1.21Drug Testing / Efficacy - Calculations
3.1.22End of Topic Test - Communicable Diseases
3.1.23Exam-Style Questions - Microorganisms & Disease
3.2Monoclonal Antibodies
4Bioenergetics
4.1Photosynthesis
4.1.1Photosynthesis
4.1.2Photosynthesis Equation
4.1.3Rate of Photosynthesis
4.1.4Limiting Factors
4.1.5Photosynthesis in Farming
4.1.6Uses of Glucose
4.1.7Photosynthesis - Calculations
4.1.8Photosynthesis Experiments
4.1.9Grade 9 - Photosynthesis Experiment
4.1.10Exam-Style Questions - Rate of Photosynthesis
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
5.2.5Reflexes Practical
5.2.6Exam-Style Questions - Nervous System
5.2.7The Brain: Key Facts
5.2.8The Brain: Brain Areas
5.2.9The Brain: Neuro Techniques
5.2.10Eye Anatomy
5.2.11Eye Function
5.2.12Eye Defects
5.2.13Control of Body Temperature
5.2.14Thermoregulation - Sweating & Shivering
5.2.15Thermoregulation - Body Hair
5.2.16Thermoregulation - Blood Vessels
5.2.17Body Temperature HyperLearning
5.2.18End of Topic Test - Human Nervous System
5.3Hormonal Coordination in Humans
5.3.1Endocrine Glands
5.3.2The Endocrine System
5.3.3Thyroxine
5.3.4Adrenaline
5.3.5Blood Glucose
5.3.6Detecting Glucose
5.3.7Type 1 Diabetes
5.3.8Type 2 Diabetes
5.3.9Water Balance
5.3.10Kidneys
5.3.11Urea
5.3.12Urine Production
5.3.13Urine
5.3.14Dialysis
5.3.15Dialysis - Pros & Cons
5.3.16Transplants
5.3.17Transplants - Pros & Cons
5.3.18Puberty
5.3.19Menstruation
5.3.20Menstrual Hormones
5.3.21Menstrual Cycle
5.3.22Female Contraception - The Pill
5.3.23Female Contraception - Other Options
5.3.24Female Contraception - Diaphragm & IUDs
5.3.25Male Contraception - Condoms
5.3.26Male Contraception - Sterilisation
5.3.27Male Contraception - 'Natural Methods'
5.3.28Hormones for Infertility
5.3.29In Vitro Fertilisation
5.3.30Fertility Treatments - Pros & Cons
5.3.31End of Topic Test - Homeostasis & Hormones
5.3.32Grade 9 - Hormonal Coordination
5.3.33Exam-Style Questions - Hormones & Contraception
6Inheritance, Variation & Evolution
6.1Reproduction
6.1.1Cell Division
6.1.2Meiosis
6.1.3Sexual Reproduction
6.1.4Asexual Reproduction
6.1.5Sexual Reproduction Advantages
6.1.6Asexual Reproduction Advantages
6.1.7Genome
6.1.8Genome Sequencing
6.1.9DNA
6.1.10Protein Synthesis
6.1.11Mutations
6.1.12Alleles
6.1.13Genotype vs Phenotype
6.1.14Punnett Squares
6.1.15Inherited Disorders
6.1.16Family Trees
6.1.17Genetic Crosses - Calculations
6.1.18Genome Screening
6.1.19Sex Determination
6.1.20End of Topic Test - Reproduction
6.1.21Exam-Style Questions - DNA & Genetics
6.2Variation & Evolution
6.2.1Variation
6.2.2Evolution
6.2.3Natural Selection
6.2.4Selective Breeding
6.2.5Uses of Selective Breeding
6.2.6Dangers of Selective Breeding
6.2.7Genetic Engineering
6.2.8Uses of Genetic Modification
6.2.9Advantages of Genetic Modification
6.2.10Disadvantages of Genetic Modification
6.2.11Cloning
6.2.12Cloning Plants
6.2.13Cloning Animals
6.2.14Adult Cell Cloning
6.2.15End of Topic Test - Variation & Evolution
6.2.16Exam-Style Questions - Selective Breeding
6.3Genetics & Evolution
7Ecology
7.1Adaptations & Interdependence
7.2Organisation of Ecosystems
7.2.1Population Dynamics
7.2.2Impact of Environmental Change
7.2.3Causes of Environmental Change
7.2.4Assessing Ecosystems
7.2.5Organism Abundance
7.2.6Required Practical - Using Quadrats
7.2.7Assessing Ecosystems - Calculations
7.2.8The Carbon Cycle
7.2.9The Water Cycle
7.2.10The Cycling of Materials
7.2.11Decay
7.2.12Anaerobic Decay
7.2.13Biogas Generators
7.2.14Required Practical - Decay
7.2.15End of Topic Test - Organisation of Ecosystems
7.2.16Grade 9 - Ecosystems
7.2.17Exam-Style Questions - Decomposition
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 - Root Hair Cells
1.1.19Cell Specialisation in Plants - Xylem
1.1.20Cell Specialisation in Plants - Phloem
1.1.21Microscopy
1.1.22Magnification
1.1.23Developments in Microscopy
1.1.24Microscope Practical
1.1.25Microscopy - Calculations
1.1.26Culturing Microorganisms
1.1.27Contamination
1.1.28Avoiding Contamination
1.1.29Calculating Bacteria
1.1.30Calculating Bacteria - Calculations
1.1.31End of Topic Test - What's in Cells?
1.1.32Exam-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
1.3.8Required Practical - Osmosis
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
2.4.12Comparing Treatments of Heart Disease
2.4.13Cancer
2.4.14Cancer Risk Factors
2.4.15End of Topic Test - Non-Communicable Diseases
2.4.16Exam-Style Questions - Coronary Heart Disease
2.5Plant Tissues, Organs & Systems
2.5.1Plant Tissues
2.5.2Leaves
2.5.3Transpiration
2.5.4Rate of Transpiration
2.5.5Measuring Transpiration
2.5.6Translocation
2.5.7Transpiration Tissues - Xylem Cells
2.5.8Transpiration Tissues - Root Hair Cells
2.5.9Stomata
2.5.10Stages of Stomata
2.5.11Premium Knowledge - Transpiration
2.5.12End of Topic Test - Plants
2.5.13Exam-Style Questions - Plant Tissues
3Infection & Response
3.1Communicable Disease
3.1.1Spreading Disease
3.1.2Causing Diseases
3.1.3Preventing Infection
3.1.4Viruses
3.1.5Examples of Viruses
3.1.6Bacteria
3.1.7Fungi
3.1.8Protists
3.1.9Human Defence Systems - Non-Specific Defences
3.1.10Human Defence Systems - Immune Systems
3.1.11Antibodies
3.1.12Vaccinations
3.1.13Grade 9 - Immune System
3.1.14Antibiotics
3.1.15Antibiotic Resistance
3.1.16Drug Discovery
3.1.17Developing New Drugs
3.1.18Drug Testing
3.1.19Drug Testing in Laboratories
3.1.20Double-Blind Trials
3.1.21Drug Testing / Efficacy - Calculations
3.1.22End of Topic Test - Communicable Diseases
3.1.23Exam-Style Questions - Microorganisms & Disease
3.2Monoclonal Antibodies
4Bioenergetics
4.1Photosynthesis
4.1.1Photosynthesis
4.1.2Photosynthesis Equation
4.1.3Rate of Photosynthesis
4.1.4Limiting Factors
4.1.5Photosynthesis in Farming
4.1.6Uses of Glucose
4.1.7Photosynthesis - Calculations
4.1.8Photosynthesis Experiments
4.1.9Grade 9 - Photosynthesis Experiment
4.1.10Exam-Style Questions - Rate of Photosynthesis
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
5.2.5Reflexes Practical
5.2.6Exam-Style Questions - Nervous System
5.2.7The Brain: Key Facts
5.2.8The Brain: Brain Areas
5.2.9The Brain: Neuro Techniques
5.2.10Eye Anatomy
5.2.11Eye Function
5.2.12Eye Defects
5.2.13Control of Body Temperature
5.2.14Thermoregulation - Sweating & Shivering
5.2.15Thermoregulation - Body Hair
5.2.16Thermoregulation - Blood Vessels
5.2.17Body Temperature HyperLearning
5.2.18End of Topic Test - Human Nervous System
5.3Hormonal Coordination in Humans
5.3.1Endocrine Glands
5.3.2The Endocrine System
5.3.3Thyroxine
5.3.4Adrenaline
5.3.5Blood Glucose
5.3.6Detecting Glucose
5.3.7Type 1 Diabetes
5.3.8Type 2 Diabetes
5.3.9Water Balance
5.3.10Kidneys
5.3.11Urea
5.3.12Urine Production
5.3.13Urine
5.3.14Dialysis
5.3.15Dialysis - Pros & Cons
5.3.16Transplants
5.3.17Transplants - Pros & Cons
5.3.18Puberty
5.3.19Menstruation
5.3.20Menstrual Hormones
5.3.21Menstrual Cycle
5.3.22Female Contraception - The Pill
5.3.23Female Contraception - Other Options
5.3.24Female Contraception - Diaphragm & IUDs
5.3.25Male Contraception - Condoms
5.3.26Male Contraception - Sterilisation
5.3.27Male Contraception - 'Natural Methods'
5.3.28Hormones for Infertility
5.3.29In Vitro Fertilisation
5.3.30Fertility Treatments - Pros & Cons
5.3.31End of Topic Test - Homeostasis & Hormones
5.3.32Grade 9 - Hormonal Coordination
5.3.33Exam-Style Questions - Hormones & Contraception
6Inheritance, Variation & Evolution
6.1Reproduction
6.1.1Cell Division
6.1.2Meiosis
6.1.3Sexual Reproduction
6.1.4Asexual Reproduction
6.1.5Sexual Reproduction Advantages
6.1.6Asexual Reproduction Advantages
6.1.7Genome
6.1.8Genome Sequencing
6.1.9DNA
6.1.10Protein Synthesis
6.1.11Mutations
6.1.12Alleles
6.1.13Genotype vs Phenotype
6.1.14Punnett Squares
6.1.15Inherited Disorders
6.1.16Family Trees
6.1.17Genetic Crosses - Calculations
6.1.18Genome Screening
6.1.19Sex Determination
6.1.20End of Topic Test - Reproduction
6.1.21Exam-Style Questions - DNA & Genetics
6.2Variation & Evolution
6.2.1Variation
6.2.2Evolution
6.2.3Natural Selection
6.2.4Selective Breeding
6.2.5Uses of Selective Breeding
6.2.6Dangers of Selective Breeding
6.2.7Genetic Engineering
6.2.8Uses of Genetic Modification
6.2.9Advantages of Genetic Modification
6.2.10Disadvantages of Genetic Modification
6.2.11Cloning
6.2.12Cloning Plants
6.2.13Cloning Animals
6.2.14Adult Cell Cloning
6.2.15End of Topic Test - Variation & Evolution
6.2.16Exam-Style Questions - Selective Breeding
6.3Genetics & Evolution
7Ecology
7.1Adaptations & Interdependence
7.2Organisation of Ecosystems
7.2.1Population Dynamics
7.2.2Impact of Environmental Change
7.2.3Causes of Environmental Change
7.2.4Assessing Ecosystems
7.2.5Organism Abundance
7.2.6Required Practical - Using Quadrats
7.2.7Assessing Ecosystems - Calculations
7.2.8The Carbon Cycle
7.2.9The Water Cycle
7.2.10The Cycling of Materials
7.2.11Decay
7.2.12Anaerobic Decay
7.2.13Biogas Generators
7.2.14Required Practical - Decay
7.2.15End of Topic Test - Organisation of Ecosystems
7.2.16Grade 9 - Ecosystems
7.2.17Exam-Style Questions - Decomposition
7.3Biodiversity
7.4Trophic Levels
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