4.5.1
The Circulatory System
The Circulatory System
The Circulatory System
Complex multicellular organisms require a specialised system for transporting nutrients throughout their bodies and removing waste products.


Heart
Heart
- The heart is the centre of the circulatory system.
- Mammals have a double circulatory system. This means blood flows through the heart twice in one circuit.
- Deoxygenated blood is pumped to the lungs.
- Oxygenated blood is pumped around the body.


Coronary arteries
Coronary arteries
- The heart is a muscle that is constantly contracting and relaxing.
- The heart muscle needs a constant supply of oxygen for respiration.
- The coronary arteries supply blood to the heart.


Pulmonary artery & vein
Pulmonary artery & vein
- Deoxygenated blood is pumped out of the heart to the lungs via the pulmonary artery.
- Oxygen diffuses into the deoxygenated blood in the lungs and the blood becomes oxygenated.
- Oxygenated blood flows into the heart from the lungs via the pulmonary vein.


Aorta & vena cava
Aorta & vena cava
- Oxygenated blood is pumped out of the heart around the body via the aorta.
- Blood in the aorta is very high pressure to ensure the blood can be pumped to all the tissues in the body.
- Oxygen dissociates from the blood at respiring cells in the body and the blood becomes deoxygenated.
- Deoxygenated blood flows into the heart from the body via the vena cava.


Renal artery & vein
Renal artery & vein
- Oxygenated blood flows out of the aorta to the kidneys.
- Oxygenated blood enters the kidneys through the renal artery.
- Oxygen diffuses out of the blood to be used in the kidney cells and the blood becomes deoxygenated.
- Deoxygenated blood flows out of the kidneys via the renal vein.
1Principles of Science I
1.1Structure & Bonding
1.1.1Atomic Model
1.1.2Electron Shells, Sub-Shells & Orbitals
1.1.3Ionic Bonding
1.1.4Representing Ionic Bonds
1.1.5Covalent Bonding
1.1.6Representing Covalent Bonds
1.1.7Metallic Bonding
1.1.8Intermolecular Forces
1.1.9Intermolecular Forces 2
1.1.10End of Topic Test - Bonding
1.1.11Relative Masses
1.1.12The Mole
1.1.13Molar Calculations
1.1.14Molar Calculations 2
1.1.15Empirical & Molecular Formulae
1.1.16Balanced Equations
1.1.17Percentage Yield
1.1.18End of Topic Test - Amount of Substance
1.2Properties of Substances
1.2.1The Periodic Table
1.2.2Ionisation Energy
1.2.3Factors Affecting Ionisation Energies
1.2.4Trends of Ionisation
1.2.5Trends in the Periodic Table
1.2.6Polarity
1.2.7Metals & Non-Metals
1.2.8Alkali Metals
1.2.9Alkaline Earth Metals
1.2.10Reactivity of Alkaline Earth Metals
1.2.11Redox
1.2.12Transition Metals
1.2.13Redox Reactions of Transition Metals
1.3Cell Structure & Function
1.4Cell Specialisation
1.5Tissue Structure & Function
1.5.1Human Gas Exchange
1.5.2Blood Vessels
1.5.3Atherosclerosis
1.5.4Skeletal Muscle
1.5.5Slow & Fast Twitch Fibres
1.5.6Neurones
1.5.7Speed of Transmission
1.5.8Action Potentials
1.5.9End of Topic Test - Neurones & Action Potentials
1.5.10Synapses
1.5.11Types of Synapse
1.5.12Medical Application
1.5.13End of Topic Test - Synapses
1.5.14Chemical Brain Imbalances
1.5.15Effect of Drugs on the Brain
1.6Working with Waves
1.7Waves in Communication
2Practical Scientific Procedures and Techniques
3Science Investigation Skills
3.1Scientific Processes
3.2Data Handling & Analysis
3.3Enzymes in Action
3.4Diffusion
3.5Plants & Their Environment
3.6Energy Content in Fuels
4Principles of Science II
4.1Extracting Elements
4.2Relating Properties to use of Substances
4.3Organic Chemistry
4.4Energy Changes in Industry
4.5The Circulatory System
4.5.1The Circulatory System
4.5.2Blood Vessels
4.5.3Blood Transfusion & the ABO Rhesus System
4.5.4The Heart
4.5.5The Cardiac Cycle
4.5.6Cardiac Output
4.5.7Coordination of Heart Action
4.5.8Heart Dissection
4.5.9Controlling Heart Rate
4.5.10Electrocardiograms
4.5.11Cardiovascular Disease
4.5.12Investigating Heart Rates
4.6Ventilation & Gas Exchange
4.7Urinary System
4.9Thermal Physics
4.9.1Power & Efficiency
4.9.2Work & Energy
4.9.3Conservation of Energy
4.9.4Pressure
4.9.5First Law of Thermodynamics
4.9.6Second Law of Thermodynamics
4.9.7Heat Engines, Heat Pumps & Refrigerators
4.9.8Non-Flow Processes
4.9.9p-V Diagrams
4.9.10Ideal Gases
4.9.11Ideal Gases 2
4.9.12Thermal Energy Transfer
4.9.13Thermal Energy Transfer Experiments
4.10Materials
5Contemporary Issues in Science
5.1Contemporary Issues in Science
5.2Analysing Scientific Information
Jump to other topics
1Principles of Science I
1.1Structure & Bonding
1.1.1Atomic Model
1.1.2Electron Shells, Sub-Shells & Orbitals
1.1.3Ionic Bonding
1.1.4Representing Ionic Bonds
1.1.5Covalent Bonding
1.1.6Representing Covalent Bonds
1.1.7Metallic Bonding
1.1.8Intermolecular Forces
1.1.9Intermolecular Forces 2
1.1.10End of Topic Test - Bonding
1.1.11Relative Masses
1.1.12The Mole
1.1.13Molar Calculations
1.1.14Molar Calculations 2
1.1.15Empirical & Molecular Formulae
1.1.16Balanced Equations
1.1.17Percentage Yield
1.1.18End of Topic Test - Amount of Substance
1.2Properties of Substances
1.2.1The Periodic Table
1.2.2Ionisation Energy
1.2.3Factors Affecting Ionisation Energies
1.2.4Trends of Ionisation
1.2.5Trends in the Periodic Table
1.2.6Polarity
1.2.7Metals & Non-Metals
1.2.8Alkali Metals
1.2.9Alkaline Earth Metals
1.2.10Reactivity of Alkaline Earth Metals
1.2.11Redox
1.2.12Transition Metals
1.2.13Redox Reactions of Transition Metals
1.3Cell Structure & Function
1.4Cell Specialisation
1.5Tissue Structure & Function
1.5.1Human Gas Exchange
1.5.2Blood Vessels
1.5.3Atherosclerosis
1.5.4Skeletal Muscle
1.5.5Slow & Fast Twitch Fibres
1.5.6Neurones
1.5.7Speed of Transmission
1.5.8Action Potentials
1.5.9End of Topic Test - Neurones & Action Potentials
1.5.10Synapses
1.5.11Types of Synapse
1.5.12Medical Application
1.5.13End of Topic Test - Synapses
1.5.14Chemical Brain Imbalances
1.5.15Effect of Drugs on the Brain
1.6Working with Waves
1.7Waves in Communication
2Practical Scientific Procedures and Techniques
3Science Investigation Skills
3.1Scientific Processes
3.2Data Handling & Analysis
3.3Enzymes in Action
3.4Diffusion
3.5Plants & Their Environment
3.6Energy Content in Fuels
4Principles of Science II
4.1Extracting Elements
4.2Relating Properties to use of Substances
4.3Organic Chemistry
4.4Energy Changes in Industry
4.5The Circulatory System
4.5.1The Circulatory System
4.5.2Blood Vessels
4.5.3Blood Transfusion & the ABO Rhesus System
4.5.4The Heart
4.5.5The Cardiac Cycle
4.5.6Cardiac Output
4.5.7Coordination of Heart Action
4.5.8Heart Dissection
4.5.9Controlling Heart Rate
4.5.10Electrocardiograms
4.5.11Cardiovascular Disease
4.5.12Investigating Heart Rates
4.6Ventilation & Gas Exchange
4.7Urinary System
4.9Thermal Physics
4.9.1Power & Efficiency
4.9.2Work & Energy
4.9.3Conservation of Energy
4.9.4Pressure
4.9.5First Law of Thermodynamics
4.9.6Second Law of Thermodynamics
4.9.7Heat Engines, Heat Pumps & Refrigerators
4.9.8Non-Flow Processes
4.9.9p-V Diagrams
4.9.10Ideal Gases
4.9.11Ideal Gases 2
4.9.12Thermal Energy Transfer
4.9.13Thermal Energy Transfer Experiments
4.10Materials
5Contemporary Issues in Science
5.1Contemporary Issues in Science
5.2Analysing Scientific Information
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