5.3.6
Urine
Kidneys - Urine Production
Kidneys - Urine Production
Each kidney contains millions of very small structures called nephrons. There are two stages in the process of urine production. These stages happen in every nephron.
![Illustrative background for Ultrafiltration](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/filter,h_400,q_80,w_640.jpg)
![Illustrative background for Ultrafiltration ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/filter,h_400,q_80,w_640.jpg)
Ultrafiltration
Ultrafiltration
- The blood is filtered and all water, urea and salts move into the nephron tubule.
- Blood cells and proteins remain in the blood as they are too big to move across the capillary walls.
![Illustrative background for Selective reabsorption](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/2.3.1%20-%20Blood%20vessels/blood-1813410_640-min,h_400,q_80,w_640.jpg)
![Illustrative background for Selective reabsorption ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/2.3.1%20-%20Blood%20vessels/blood-1813410_640-min,h_400,q_80,w_640.jpg)
Selective reabsorption
Selective reabsorption
- Useful substances, including some water, are reabsorbed from the tubule back into the bloodstream.
- This leaves all urea, excess salts and excess water in the tubule.
- This mixture forms urine, which is collected by the kidneys and travels to the bladder to be stored and then excreted.
Water in the Blood
Water in the Blood
The volume of urine produced depends on the internal conditions. The volume of water in the blood is monitored by the hypothalamus in the brain. This is how the body responds to having too much or too little water in the blood:
![Illustrative background for Too little water](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/shutterstock_304096067-min,h_400,q_80,w_640.jpg)
![Illustrative background for Too little water ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/shutterstock_304096067-min,h_400,q_80,w_640.jpg)
Too little water
Too little water
- The hypothalamus triggers the pituitary gland to release anti-diuretic hormone (ADH).
- This increases the permeability (ability of things to pass through) of the kidney tubules. This means that more water is reabsorbed back into the bloodstream.
- This results in a small volume of concentrated urine.
![Illustrative background for Too much water](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/rsz_watersplash,h_400,q_80,w_640.jpg)
![Illustrative background for Too much water ?? "content](https://image-v2.cdn.app.senecalearning.com/courseImages/biology/5.3.2-%20Control%20of%20water%20balance/rsz_watersplash,h_400,q_80,w_640.jpg)
Too much water
Too much water
- The hypothalamus triggers the pituitary gland to stop the release of anti-diuretic hormone (ADH).
- This reduces the permeability of the kidney tubules. This means that less water is reabsorbed back into the bloodstream.
- This results in a large volume of dilute 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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