1. The digestive system consists of digestive tract and digestive gland, which is mainly used to digest, absorb and excrete food and provide material and energy for the body.
2, respiratory system, the main function is to inhale oxygen and exhale carbon dioxide to ensure normal metabolism.
3. The main function of the circulatory system is to transport nutrients.
4. The function of urinary system is to discharge the metabolic waste of human body.
The function of reproductive system is to reproduce.
6. The function of the nervous system is to regulate the activities of the body and organ system.
7. The function of motion system is motion, support and protection.
8. The endocrine system can regulate the human body.
The human body is divided into four main tissues:
1. Epithelial tissue is composed of epithelial cells, which are closely arranged and have protective and secretory functions.
Second, there are many kinds of connective tissues and well-developed interstitial cells. Medical education network is widely distributed and has the functions of support, connection, protection and nutrition.
Thirdly, muscle tissue is mainly composed of muscle cells, which have the functions of contraction and relaxation.
Fourth, nerve tissue is composed of nerve cells, which can receive stimulation, generate and transmit excitement.
The above contents refer to:
Baidu Encyclopedia-Eight Systems of Human Body