Anatomy & Organs

Organ System – Structure, Function & Diseases

Organ system

The human body consists of nine different organ systems , also called functional systems. These systems influence each other. If one system fails, the others, or parts of them, are also affected.

What is the organ system?

The human organ system is a group of organs that perform a specific job in the body and work closely together. All functions that are important to life are controlled by these systems. Neither of these systems can operate independently of the other, with numerous interactions and overlaps.

The liver , for example, has to fulfill a variety of functions and is therefore assigned to several organ systems. The same applies to the immune system , which plays the all-important role in defending against pathogens . Here it is the lymphatic system that forms the basis of the immune system and is connected to all organs. Since there is no part of the human organism that cannot be attacked by pathogens, all organ systems must also be involved in the work of the immune system.

The musculoskeletal system, which includes the skeleton and its muscles , must also coordinate numerous functions in the body. While the muscles have the task of providing support, they also have to expel certain components from the body in the digestive system . Two different functions performed by the same organ system.

Anatomy & Structure

The nervous system consists of two parts, the autonomic and the somatic nervous system, which form a close-meshed network with neurons and glial cells . The cardiovascular system is made up of two halves of the heart, each with an atrium and ventricle, as well as blood vessels , veins and arteries .

Anatomically, the respiratory system begins in the nose and ends in the alveoli . In between are the pharynx , larynx , trachea and bronchi . A distinction is made between the upper and lower airways. The upper includes the nasal cavity with the sinuses , oral cavity and pharynx. The lower respiratory tract includes the trachea, bronchi with their bronchioles, larynx and alveoli. Similarly, the digestive system begins eating in the mouth , the stomach and intestineshappens and ends in the anus with the excretion of feces.

Despite their different tasks, the urinary and genital organs come under the term urogenital system. This is related to the common embryological development, as well as the close functional and topographical connection. The endocrine system is distributed among various glands and tissues in the body, such as the pineal gland in the brain , the thyroid gland or the pancreas . Within the movement system, the body is formed by the skeleton, and the associated muscles ensure mobility.

The skin is a surface organ with around 1.8 square meters. Your organ system consists of five distinct layers: epidermis , dermis , subcutis , integuments, and inguinal skin. The immune system is divided into non-specific and specific defence. While the non-specific is innate, the specific must first be acquired.

Function & Tasks

All nine organ systems are responsible for a functioning interaction in the human organism. The nervous system is responsible for the perception, processing and control of stimuli and reactions. Both external and internal changes are recorded, analyzed and related to one another by neurons and glial cells. The cardiovascular system is the transport system responsible for blood circulation .

The diverse tasks of the blood include thermoregulation and blood clotting , the transport of oxygen from the lungs to the tissues. Blood is also an important medium that controls the transport of hormones between the organ systems. The lungs play an important part in the respiratory system with their gas exchange in the alveoli. The air-conducting hollow organs nose, throat, larynx and trachea are responsible for filtering, warming and humidifying the breathing air. The digestive system is responsible for the uptake and absorption of food. What can be used from the food components is transported further, what cannot be used is excreted.

Various microorganisms and enzymes are involved in digestion . Excretion and reproduction are the central tasks of the urogenital system with its urinary and genital organs, which would not function without the hormone system. As chemical messengers , hormones are responsible for various metabolic processes, reproduction and growth. The support and movement system gives the skeleton with its musculature a firm shape and at the same time ensures targeted mobility. Tendons , tendon sheaths , ligaments , and bursa serve as connecting elementsand sesame legs. The skin is both the largest and most versatile organ system and serves as a protective covering for the inside and outside. It ensures thermoregulation, stores energy in the form of fat, protects against environmental influences and plays a role in metabolism and immunology.

The immune system has to fight off pathogens with a finely tuned network. A distinction is made between a cellular and a humoral part. The cellular immune defense includes specialized immune cells that are either free in the blood or firmly stationed in certain tissues. The humoral portion of defense is based on plasma proteins , which include interleukins , antibodies , and complement factors.


Whether allergy , meningitis or arthrosis – the number of diseases that can affect the individual organ systems is large and covers the entire spectrum. Due to the close, almost always comprehensive interaction of the systems, it is almost impossible for an illness to occur as a single incident.

The cold is not only limited to the nose, but also affects the respiratory system. An immune deficiency affects the entire body. And arthrosis does not only occur in the knee , but also affects bones, muscles and tendons.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.