Human body has many organs which play an important role in body physiology.
These organs are differentiated into organ systems for ease of study.
The concept of an organ comes from the fact that a group of tissues are involved in a common function by forming an anatomical structure. This anatomical structure is called an organ.
The tissues in the organ are made up of different types of cells.
A set of organs are referred to an organ systems due to their distinct physiological goals in the body.
For example, digestive system is an organ system comprising organs like stomach, esophagus, buccal-cavity, intestine, rectum, pancreas, liver etc. They are all concerned with one important physiological function namely digestion. If one of the organs is disturbed then the whole function of digestion is in trouble. So these organs are perfectly interlinked and connected.
In most cases, every organ in the organ system has only one specific physiologic function.
But some organs may be a part of one or more organ systems. For example, liver is a part of digestive system but also plays a prominent role in excretion system. It helps metabolize drugs and other waste from body through urine.
The organ systems are similar in terms of function and anatomy starting from amphibians to higher animals. The different organ systems in human body include.
1.Skeletal system: This system is made of bone cells and cartilage cells which are hardened. They are meant to provide the body frame, shape, support to other organs and also protect them. This system is also flexible at places called joints. These joints help in body movements in coordination with skeletal muscles.
2. Muscular system: This system has muscles of three types as skeletal muscles, cardiac muscles and smooth muscles. Their prime role is to provide movement in the body. Skeletal muscles help in moving the body from one place to another by walking, running, moving, lifting etc. On the other hand the cardiac muscles in the heart help in movement of the blood in the body to the deep and remote corners of the whole body.
3. Respiratory system: The respiratory system is one which is meant to oxygenate the body. The oxygen in the body help to generate energy by use of glucose in the mitochondria. The respiratory system comprises of respiratory tract and diaphragm The tract includes, nose, larynx, bronchi and lungs. Besides, it helps in producing sounds, excretion (alcohol) and also metabolism.
4. Circulatory system: The circulatory system is one which comprises of blood, blood vessels (arteries, veins & capillaries) and heart. This system is involved in supply of oxygen and nutrition to all parts of the body. Further it also transports waste from all parts of the body to the excretory organs.
5. Digestive system: This system as mentioned before involves stomach, esophagus, intestine, mouth, teeth, throat, rectum and anus. It is an important system to facilitate entry of nutrients into the body. The food is breakdown to small carbohydrates, amino acids and fatty acids for easy absorption into the body.
6. Nervous system: This is a system which controls all other organ systems. It regulates the whole body physiology. It comprises of brain, spinal cord, sympathetic nervous system and also parasympathetic nervous system. It stimulates release of hormones, body movement through muscles, controls respiration, heart beat etc.
7. Endocrine system: This is a specialized system which regulates the physiology by secretion of biochemical substances in the body. These biochemical substances are called hormones. These hormones are of different types and are meant to regulate specific physiological purposes.
8. Reproductive system: This is the organ system which is responsible for continuation of species. It helps in formation of offspring to keep up the life. This system is quite interesting in that it is just one part and incomplete without the support from another opposite sex organism.
9. Lymphatic system: This is the micro circulation system which drains fluids from minutes spaces of the cells and tissues after blood has supplied the nutrients. This system is made of lymphatic nodes and lymphatic vessels, spleen, tonsils, thymus etc. It is also a body defense and kills any bacteria, virus and other parasites moving in the body.
10. Excretory system: This system helps to remove the toxins from the body. This consists of organs like kidneys, skin, liver, lungs, saliva etc. Any substance in the body is first converted to water soluble form by liver. This is transported by blood to excretory organs like kidney, skin, lungs from where it is excreted from the body.
11. Humoral system (immune system): This system is a natural defense to the body. This comprises of lymph, white blood cells and humoral substance namely antibodies.
12. Integumentary system: This is a covering system which covers the whole body surface. It keeps it safe from damage, wear and also infections. The organs under this system is skin its hair etc. It also prevents dehydration and heat loss.
Though we divide the body into various organs and organ systems, still if one system is affected, other systems slowly decline and cease to function. So they are interconnected and not single in living.