Table of ContentsView AllTable of ContentsCirculatoryLymphaticRespiratoryIntegumentaryEndocrineGastrointestinalUrinaryMusculoskeletalNervousImmuneReproductive
Table of ContentsView All
View All
Table of Contents
Circulatory
Lymphatic
Respiratory
Integumentary
Endocrine
Gastrointestinal
Urinary
Musculoskeletal
Nervous
Immune
Reproductive
An organ system is a group of organs that work together in the body to perform a complex function, such as pumping blood or processing and utilizing nutrients.There are 11 major organ systems in the human body:The circulatory(cardiovascular) systemThe lymphatic systemThe respiratory systemTheintegumentarysystemThe endocrine systemThe gastrointestinal (digestive) systemThe urinary (excretory) systemThe musculoskeletal systemThe nervous systemThe reproductive systemThe immune systemOrgan systems work together to keep the body in good health. For example, the circulatory and digestive systems work jointly to deliver nutrients throughout the body.Except for the reproductive system, each system is necessary for survival.Peter Dazeley / Getty ImagesThe Circulatory SystemThecirculatory systemtransports oxygen and nutrients to all corners of the body. It also carries away carbon dioxide and other waste products.When people talk about this organ system, they’re usually talking about the cardiovascular system at large, which includes:The heartBloodBlood vessels (arteries and veins)The circulatory system maintains blood flow within a certain pressure range so that the blood can make it to everywhere it needs to go.Blood pressurethat’s too high puts extra stress on other organs and tissues. Low blood pressure means the blood—and its nutrients—won’t make it to where it needs to go.How Much Blood Is in Your Body?The Lymphatic SystemThelymphatic systemis the drainage system of the body. It plays an important role in your immunity, blood pressure regulation, digestion, and other functions.This organ system carries excess fluid, proteins, fats, bacteria, and other substances away from the cells and spaces between cells. It does this using:Lymph vesselsLymph nodesLymph ductsVarious glandsThe lymphatic vessels move the fluid into collecting ducts, which return the fluid to your bloodstream.The lymphatic system also helps create and circulate vital cells that fight disease, which is why it is also a part of the immune system. This includeslymphocytesandmonocytes(white blood cells) and antibodies (proteins that recognize bacteria and viruses).Benefits of Lymphatic DrainageThe Respiratory SystemThe respiratory system is responsible forbreathing, which is the controlled movement of air in and out of the body (ventilation). It also moves oxygen and carbon dioxide into and out of the bloodstream (respiration).This organ system contains the following:LungsTrachea(windpipe)Airways of the respiratory treeOne of the least understood responsibilities of the respiratory system is to help regulate the body’spH balance(the body’s balance of acids and bases).Carbon dioxide is made into carbonic acid, which affects the pH balance. The respiratory system regulates this pH level when it releases carbon dioxide from the body.Breathing issues may indicate a condition that affects the body’s acidity.Differences Between Respiratory Arrest and Cardiac ArrestThe Integumentary SystemTheintegumentary systemis unique because it is the largest and only single-organ system in the body. It protects the body from the external environment and helps regulate body temperature.The integumentary system is theskinand all the structures in it, including:Sweat glandsHair folliclesNailsNervesThe Skin and How It WorksThe Endocrine SystemTheendocrine systemmostly regulates metabolism and uses the products of digestion. Along with the nervous system and immune system, it’s generally considered one of the most complicated systems in the body.This organ system includes all the glands that secrete hormones into the bloodstream, including:AdrenalGonads (ovaries and testicles)HypothalamusPancreasParathyroidPinealPituitaryThymusThyroidThe Endocrine System and How It WorksThe Digestive SystemThegastrointestinal (GI) systemis sometimes referred to as the gut or the digestive system. It is responsible for breaking down foods into nutrients, which the body needs for energy, growth, and cell repair.This system includes all the organs that carry food from where it enters the body to where it exits, including the following:MouthEsophagusStomachSmall intestineLarge intestineRectumAnusThe pancreas, gallbladder, and liver are also part of this organ system.The GI tract and the endocrine system have a lot of interaction. The endocrine system produces the hormones that regulate digestion and the absorption of nutrients.The GI system also owes a lot to thevagus nerve, the main contributor to the parasympathetic nervous system, which regulates bodily functions. The vagus nerve is involved in slowing metabolism, lowering heart rate and blood pressure, and stimulating the mechanics of digestion.One Organ, Two Organ SystemsSome organs belong to more than one organ system. The pancreas, for example, can be considered a part of the digestive system because it secretes enzymes that help the body break down fat, protein, and starch. It is also part of the endocrine system because it produces hormones that help regulate blood sugar.Tour Your Digestive SystemThe Urinary (Excretory) SystemThe urinary system includes:KidneysUretersBladderUrethraThese organs work together to filter blood and remove toxins and waste from body tissues. The removal of excess fluid through this organ system also helps regulate blood pressure.Tips for Keeping Your Urinary System HealthyThe Musculoskeletal SystemThemusculoskeletal systemprovides the framework and the engine for our movement, posture, and physical abilities.This organ system includes:The skeletonAll the muscles, tendons, and ligaments attached to the skeletonMuscles in the BodyThere are three types of muscles in the body:Skeletal (voluntary)Smooth (visceral or involuntary), which are inside walls of organs like the intestinesCardiac (heart muscle)Only skeletal muscle is considered part of the musculoskeletal system.Skeletal SystemYour body’s skeletal system contains 206 bones:The 80 bones of the axial skeleton (your spine and the core of your body)The 126 bones in the appendicular skeleton (your arms, legs, and bones away from the core)In addition to providing your body’s structure and facilitating its mobility, the skeletal system contains bone marrow to produce blood and lymph cells. It stores fat in the body, as well as key minerals like calcium.What Could Be Causing My Musculoskeletal Pain?The Nervous SystemThenervous systemis a network that makes it possible for different parts of the body to communicate with one another. Think of it as your body’s command station. All body processes, reactions, thoughts, and movements stem from this organ system.The nervous system is incredibly detailed and includes:The Central Nervous SystemThe brainThe spinal cordThe Peripheral Nervous SystemAll the nerves connected to both of these organsThe nervous system contains the only tissue that isn’t fed directly through contact with blood.The Immune SystemTheimmune systemhelps the body fight against infection and other diseases. All of its organs are borrowed from other organ systems.Because of the interplay between organs from various other systems, the immune system is one of the most complicated systems of all.The primary organs of the immune system include:Lymph nodesBone marrowThymusSpleenAdenoidsTonsilsSkinImmune system organs work like sailors on a ship: Each one has a primary duty and is cross-trained for other jobs.Immune System BoostersThe Reproductive SystemThis is the only organ system that is not complete in any one body and requires another person (or medical intervention) to complete its mission, producing offspring.Themale reproductive systemconsists of the:EpididymisTestesProstateAs well as the external structures of the scrotum and penis.Thefemale reproductive systemconsists of the:VaginaUterusOvariesAside from their direct roles in reproduction, the ovaries and testicles also play important roles in the endocrine system, producing estrogen, testosterone, and progesterone.Sexual HealthSummaryThe body has 11 different organ systems. Each group of organs has a different complex function, such as movement, breathing, or digestion.In some cases, one system works closely with another on a particular task. For example, the endocrine system interacts with the gastrointestinal system to control digestion and metabolism.When your organ systems are working properly, they help your body stay in balance and maintain your health.How Much Do Your Organs Weigh?
An organ system is a group of organs that work together in the body to perform a complex function, such as pumping blood or processing and utilizing nutrients.
There are 11 major organ systems in the human body:
Organ systems work together to keep the body in good health. For example, the circulatory and digestive systems work jointly to deliver nutrients throughout the body.
Except for the reproductive system, each system is necessary for survival.
Peter Dazeley / Getty Images
The Circulatory System
Thecirculatory systemtransports oxygen and nutrients to all corners of the body. It also carries away carbon dioxide and other waste products.
When people talk about this organ system, they’re usually talking about the cardiovascular system at large, which includes:
The circulatory system maintains blood flow within a certain pressure range so that the blood can make it to everywhere it needs to go.
Blood pressurethat’s too high puts extra stress on other organs and tissues. Low blood pressure means the blood—and its nutrients—won’t make it to where it needs to go.
How Much Blood Is in Your Body?
The Lymphatic System
Thelymphatic systemis the drainage system of the body. It plays an important role in your immunity, blood pressure regulation, digestion, and other functions.
This organ system carries excess fluid, proteins, fats, bacteria, and other substances away from the cells and spaces between cells. It does this using:
The lymphatic vessels move the fluid into collecting ducts, which return the fluid to your bloodstream.
The lymphatic system also helps create and circulate vital cells that fight disease, which is why it is also a part of the immune system. This includeslymphocytesandmonocytes(white blood cells) and antibodies (proteins that recognize bacteria and viruses).
Benefits of Lymphatic Drainage
The Respiratory System
The respiratory system is responsible forbreathing, which is the controlled movement of air in and out of the body (ventilation). It also moves oxygen and carbon dioxide into and out of the bloodstream (respiration).
This organ system contains the following:
One of the least understood responsibilities of the respiratory system is to help regulate the body’spH balance(the body’s balance of acids and bases).
Carbon dioxide is made into carbonic acid, which affects the pH balance. The respiratory system regulates this pH level when it releases carbon dioxide from the body.Breathing issues may indicate a condition that affects the body’s acidity.
Differences Between Respiratory Arrest and Cardiac Arrest
The Integumentary System
Theintegumentary systemis unique because it is the largest and only single-organ system in the body. It protects the body from the external environment and helps regulate body temperature.
The integumentary system is theskinand all the structures in it, including:
The Skin and How It Works
The Endocrine System
Theendocrine systemmostly regulates metabolism and uses the products of digestion. Along with the nervous system and immune system, it’s generally considered one of the most complicated systems in the body.
This organ system includes all the glands that secrete hormones into the bloodstream, including:
The Endocrine System and How It Works
The Digestive System
Thegastrointestinal (GI) systemis sometimes referred to as the gut or the digestive system. It is responsible for breaking down foods into nutrients, which the body needs for energy, growth, and cell repair.
This system includes all the organs that carry food from where it enters the body to where it exits, including the following:
The pancreas, gallbladder, and liver are also part of this organ system.
The GI tract and the endocrine system have a lot of interaction. The endocrine system produces the hormones that regulate digestion and the absorption of nutrients.
The GI system also owes a lot to thevagus nerve, the main contributor to the parasympathetic nervous system, which regulates bodily functions. The vagus nerve is involved in slowing metabolism, lowering heart rate and blood pressure, and stimulating the mechanics of digestion.
One Organ, Two Organ SystemsSome organs belong to more than one organ system. The pancreas, for example, can be considered a part of the digestive system because it secretes enzymes that help the body break down fat, protein, and starch. It is also part of the endocrine system because it produces hormones that help regulate blood sugar.
One Organ, Two Organ Systems
Some organs belong to more than one organ system. The pancreas, for example, can be considered a part of the digestive system because it secretes enzymes that help the body break down fat, protein, and starch. It is also part of the endocrine system because it produces hormones that help regulate blood sugar.
Tour Your Digestive System
The Urinary (Excretory) System
The urinary system includes:
These organs work together to filter blood and remove toxins and waste from body tissues. The removal of excess fluid through this organ system also helps regulate blood pressure.
Tips for Keeping Your Urinary System Healthy
The Musculoskeletal System
Themusculoskeletal systemprovides the framework and the engine for our movement, posture, and physical abilities.
This organ system includes:
Muscles in the Body
There are three types of muscles in the body:
Only skeletal muscle is considered part of the musculoskeletal system.
Skeletal System
Your body’s skeletal system contains 206 bones:
In addition to providing your body’s structure and facilitating its mobility, the skeletal system contains bone marrow to produce blood and lymph cells. It stores fat in the body, as well as key minerals like calcium.
What Could Be Causing My Musculoskeletal Pain?
The Nervous System
Thenervous systemis a network that makes it possible for different parts of the body to communicate with one another. Think of it as your body’s command station. All body processes, reactions, thoughts, and movements stem from this organ system.
The nervous system is incredibly detailed and includes:
The Central Nervous System
The Peripheral Nervous System
The nervous system contains the only tissue that isn’t fed directly through contact with blood.
The Immune System
Theimmune systemhelps the body fight against infection and other diseases. All of its organs are borrowed from other organ systems.
Because of the interplay between organs from various other systems, the immune system is one of the most complicated systems of all.
The primary organs of the immune system include:
Immune system organs work like sailors on a ship: Each one has a primary duty and is cross-trained for other jobs.
Immune System Boosters
The Reproductive System
This is the only organ system that is not complete in any one body and requires another person (or medical intervention) to complete its mission, producing offspring.
Themale reproductive systemconsists of the:
Thefemale reproductive systemconsists of the:
Aside from their direct roles in reproduction, the ovaries and testicles also play important roles in the endocrine system, producing estrogen, testosterone, and progesterone.
Sexual Health
Summary
The body has 11 different organ systems. Each group of organs has a different complex function, such as movement, breathing, or digestion.
In some cases, one system works closely with another on a particular task. For example, the endocrine system interacts with the gastrointestinal system to control digestion and metabolism.
When your organ systems are working properly, they help your body stay in balance and maintain your health.
How Much Do Your Organs Weigh?
21 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Oregon State University.Structural organization of the human body.Hutchins J, Burr J, Price T, West J.The reproductive system.Institute for Quality and Efficiency in Health Care.How does the blood circulatory system work?National Cancer Institute.Introduction to the lymphatic system: components of the lymphatic system.University of Rochester Medical Center.Anatomy of the respiratory system.MedlinePlus.Alkalosis.National Library of Medicine.Physiology, Integument.Endocrine Society.Your health and hormones.Oregon State University.Structural organization of the human body.National Institute of Diabetes and Digestive and Kidney Diseases.Your digestive system & how it works.Breit S, Kupferberg A, Rogler G, Hasler G.Vagus nerve as modulator of the brain-gut axis in psychiatric and inflammatory disorders.Front Psychiatry. 2018;9:44. doi:10.3389/fpsyt.2018.00044National Cancer Institute.Endocrine system: endocrine glands & their hormones.National Cancer Institute.Urinary system: components of the urinary system.National Cancer Institute.Skeletal system: introduction to the skeletal system.National Cancer Institute.Muscular system: muscle types.National Cancer Institute.Skeletal system: divisions of the skeleton.National Cancer Institute.Nervous system: organization of the nervous system.Sweeney MD, Zhao Z, Montagne A, Nelson AR, Zlokovic BV.Blood-brain barrier: from physiology to disease and back.Physiol Rev. 2019;99(1):21-78. doi:10.1152/physrev.00050.2017Institute for Quality and Efficiency in Health Care.What are the organs of the immune system?National Library of Medicine.Physiology, male reproduction system.National Library of Medicine.Physiology, female reproduction.
21 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Oregon State University.Structural organization of the human body.Hutchins J, Burr J, Price T, West J.The reproductive system.Institute for Quality and Efficiency in Health Care.How does the blood circulatory system work?National Cancer Institute.Introduction to the lymphatic system: components of the lymphatic system.University of Rochester Medical Center.Anatomy of the respiratory system.MedlinePlus.Alkalosis.National Library of Medicine.Physiology, Integument.Endocrine Society.Your health and hormones.Oregon State University.Structural organization of the human body.National Institute of Diabetes and Digestive and Kidney Diseases.Your digestive system & how it works.Breit S, Kupferberg A, Rogler G, Hasler G.Vagus nerve as modulator of the brain-gut axis in psychiatric and inflammatory disorders.Front Psychiatry. 2018;9:44. doi:10.3389/fpsyt.2018.00044National Cancer Institute.Endocrine system: endocrine glands & their hormones.National Cancer Institute.Urinary system: components of the urinary system.National Cancer Institute.Skeletal system: introduction to the skeletal system.National Cancer Institute.Muscular system: muscle types.National Cancer Institute.Skeletal system: divisions of the skeleton.National Cancer Institute.Nervous system: organization of the nervous system.Sweeney MD, Zhao Z, Montagne A, Nelson AR, Zlokovic BV.Blood-brain barrier: from physiology to disease and back.Physiol Rev. 2019;99(1):21-78. doi:10.1152/physrev.00050.2017Institute for Quality and Efficiency in Health Care.What are the organs of the immune system?National Library of Medicine.Physiology, male reproduction system.National Library of Medicine.Physiology, female reproduction.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Oregon State University.Structural organization of the human body.Hutchins J, Burr J, Price T, West J.The reproductive system.Institute for Quality and Efficiency in Health Care.How does the blood circulatory system work?National Cancer Institute.Introduction to the lymphatic system: components of the lymphatic system.University of Rochester Medical Center.Anatomy of the respiratory system.MedlinePlus.Alkalosis.National Library of Medicine.Physiology, Integument.Endocrine Society.Your health and hormones.Oregon State University.Structural organization of the human body.National Institute of Diabetes and Digestive and Kidney Diseases.Your digestive system & how it works.Breit S, Kupferberg A, Rogler G, Hasler G.Vagus nerve as modulator of the brain-gut axis in psychiatric and inflammatory disorders.Front Psychiatry. 2018;9:44. doi:10.3389/fpsyt.2018.00044National Cancer Institute.Endocrine system: endocrine glands & their hormones.National Cancer Institute.Urinary system: components of the urinary system.National Cancer Institute.Skeletal system: introduction to the skeletal system.National Cancer Institute.Muscular system: muscle types.National Cancer Institute.Skeletal system: divisions of the skeleton.National Cancer Institute.Nervous system: organization of the nervous system.Sweeney MD, Zhao Z, Montagne A, Nelson AR, Zlokovic BV.Blood-brain barrier: from physiology to disease and back.Physiol Rev. 2019;99(1):21-78. doi:10.1152/physrev.00050.2017Institute for Quality and Efficiency in Health Care.What are the organs of the immune system?National Library of Medicine.Physiology, male reproduction system.National Library of Medicine.Physiology, female reproduction.
Oregon State University.Structural organization of the human body.
Hutchins J, Burr J, Price T, West J.The reproductive system.
Institute for Quality and Efficiency in Health Care.How does the blood circulatory system work?
National Cancer Institute.Introduction to the lymphatic system: components of the lymphatic system.
University of Rochester Medical Center.Anatomy of the respiratory system.
MedlinePlus.Alkalosis.
National Library of Medicine.Physiology, Integument.
Endocrine Society.Your health and hormones.
National Institute of Diabetes and Digestive and Kidney Diseases.Your digestive system & how it works.
Breit S, Kupferberg A, Rogler G, Hasler G.Vagus nerve as modulator of the brain-gut axis in psychiatric and inflammatory disorders.Front Psychiatry. 2018;9:44. doi:10.3389/fpsyt.2018.00044
National Cancer Institute.Endocrine system: endocrine glands & their hormones.
National Cancer Institute.Urinary system: components of the urinary system.
National Cancer Institute.Skeletal system: introduction to the skeletal system.
National Cancer Institute.Muscular system: muscle types.
National Cancer Institute.Skeletal system: divisions of the skeleton.
National Cancer Institute.Nervous system: organization of the nervous system.
Sweeney MD, Zhao Z, Montagne A, Nelson AR, Zlokovic BV.Blood-brain barrier: from physiology to disease and back.Physiol Rev. 2019;99(1):21-78. doi:10.1152/physrev.00050.2017
Institute for Quality and Efficiency in Health Care.What are the organs of the immune system?
National Library of Medicine.Physiology, male reproduction system.
National Library of Medicine.Physiology, female reproduction.
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