There are multiple organs that work together to keep the human body functioning.
Groups of organ systems work together to make complete, functional organisms.
The urinary or excretory system is where liquid waste is eliminated as urine. The excretory system starts with the kidneys, important organs for cleaning the blood and balancing water in the body. In the excretory system, the liquid part of the blood, or plasma, enters through the kidneys, where important nutrients, like sugar and some salt, are reabsorbed into the body. Compounds we don’t need, like urea or excess water, are sent to the bladder in the form of urine. Urine leaves the body through the urinary tract and exits the body at the urethra, as shown in the following illustration of the female urinary system.
In order for blood to provide oxygen to the body, the body must have a way of obtaining that oxygen. The respiratory system allows air to enter the lungs and for oxygen to diffuse into the blood en route to the body’s tissues. The entrance to the respiratory system can be found in the nose and the mouth, where air enters the body and then travels through the larynx and pharynx in the throat to the trachea or windpipe. From the trachea, right and left branches, known as bronchi, carry oxygen to the alveoli, where oxygen moves into the blood, while carbon dioxide moves into the lungs to be exhaled.
Digestive system is responsible for bringing food into the body and breaking it down to useable components. it starts at the mouth, where we ingest our food and use our saliva, teeth and tongue to bite and mash it. The food then travels through the esophagus into the stomach, where strong acids break it down even further. During the last two stages of digestion, nutrients and water are absorbed through the small intestine and the large intestine, respectively. Any remaining waste products are stored in the rectum and eliminated through the anus.
The circulatory system is responsible for transporting blood throughout the body. It consists of the heart and blood vessels known as veins, arteries and capillaries. Think of blood vessels as the highways of the body, bringing important cargo to and from the cells. In the circulatory system, blood is pumped from the heart to the lungs, so they’ll get oxygen, and then pumped to the body’s cells.
Lymphatic system – The lymphatic system is a network of tissues and organs that help rid the body of toxins, waste and other unwanted materials
Nervous system that tells our bodies what to do, none of the organ systems we’ve talked about so far would work. The organs in the human nervous system are made up of cells, called neurons, that use chemicals and electricity to send messages. This system has two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS), which you can see in the diagram below. The central nervous system consists of the brain and the spinal cord, which serve as the main control centers for the body and process all incoming and outgoing messages. The peripheral nervous system includes all the nerves in your body that bring messages to the central nervous system and from the CNS to the muscles
the endocrine system relies upon chemicals, called hormones, to send long distance messages through the body. For example, instead of communicating directly by talking to your neighbor, you decide to send him or her a letter. The main organs found in the human endocrine system are located in the brain and include the hypothalamus, thalamus and pituitary gland. They talk to other endocrine organs, like the adrenal glands, testes and ovaries to assist with other organ systems. The following is an image of the different organs that make up the endocrine system and secrete hormones.
immune system which acts like the guardian of your body by keeping harmful things, like pathogens or toxins, out and fighting any infection that gets in. It is made up of a series of tubes called lymphatic vessels, that help to screen the blood for pathogens. The immune system also includes white blood cells that patrol through the lymphatic and circulatory systems checking for invaders.
The integumentary system SKELETON & MUSCLES works with the immune system to provide structure and support for our body.
The skin is the largest organ of the body, with a total area of about 20 square feet. The skin protects us from microbes and the elements, helps regulate body temperature, and permits the sensations of touch, heat, and cold.
skin has 3 layers -
The epidermis, the outermost layer of skin, provides a waterproof barrier and creates our skin tone.
The dermis, beneath the epidermis, contains tough connective tissue, hair follicles, and sweat glands.
The deeper subcutaneous tissue (hypodermis) is made of fat and connective tissue.Skin is one organ found in this system. It protects the inside of our tissues and keeps invaders away. Hair and nails are other structural parts of the integumentary system.