The human body is an amazing thing and consists of various systems that help to maintain different bodily functions. Each system is comprised of at least two organs and these systems work together to keep the body working correctly.
The circulatory system
The circulatory system consists of the heart, vessels and blood. The heart pumps blood carrying oxygen, nutrients and hormones around the body to cells and carries waste substances such as carbon dioxide to the lungs and kidneys to be excreted.
The respiratory system
Made up of the nose, trachea and lungs, this system brings oxygen into the body to be transported to cells by the circulatory system and expels carbon dioxide.
The immune system
This system consists of white blood cells that fight infections and diseases by eliminating infected cells using antibodies.
The lymphatic system
This helps to filter out infections by generating disease-fighting antibodies.
The skeletal system
Made up of bones, tendons and ligaments, the skeletal system helps to shape the human body and protects the organs.
The excretory system
The excretory system is made up of the lungs, large intestine and kidneys and removes waste products from the human body.
The urinary system
The urinary system consists of the bladder and kidneys and expels waste, in the form of urine, from the human body via the urethra.
The endocrine system
This system is made up of many glands that produce hormones. These hormones help to control bodily functions such as metabolism, growth and sexual development.
The digestive system
Made up of the mouth, oesophagus, stomach and intestines, this system breaks down food into nutrients. These nutrients enter the bloodstream and are transported around the body. The digestive system also assists in eliminating waste.
The nervous system
Perhaps the most important human body system, the nervous system consists of the brain, spinal cord and nerves. The brain receives and processes messages sent from the nerves and tells the body what to do.
The reproductive system
This system allows humans to produce offspring. The sperm from the male fertilises the eggs in the fallopian tubes of the female. This embryo is then carried into the uterus and a foetus is developed over a period of nine months.