- The meeting of cells with each other forms the organs that meet with each other to form the organs of the body, and these organs must work jointly in a coordinated manner to secure human life.
- 📌 nervous system It is a group of nerves and specialized cells known as neurons that transmit signals between different parts of the body ▪️ The nervous system consists of two parts: _ Central nervous system: The central nervous system consists of the brain, spinal cord, and nerves. _ Peripheral nervous system: The peripheral nervous system is made up of sensory neurons, ganglia (groups of neurons), nerves that connect to each other, and the central nervous system. ▪️The functions of the nervous system: The nervous system responds to internal and external stimuli by means of signals that are sent to the muscles to contract or to the glands to secrete hormones. The following are the most important functions of the nervous system: ✔️ Organizing different mental activities. ✔️ Regulating body movement. ✔️ Control involuntary body functions such as heartbeat, digestion, and breathing. ✔️ Responding to emergencies by releasing the hormone adrenaline, which is also known as the hit-and-run hormone. ✔️Control all the senses of the body 📌 Immune system The role of the immune system is to protect against disease or its potentially harmful pathogens. When the immune system is working properly, it identifies a variety of threats, including viruses, bacteria and parasites, and distinguishes them from the body's healthy tissues. ▪️ The parts of the immune system: _White blood cells _lymph nodes _spleen _thymus gland _Bone Marrow Skin and mucous membranes ▪️ The functions of the immune system: Function of the immune system The following are the main functions of the immune system: ✔️ Trying to eliminate pathogens such as bacteria, viruses, and parasites. ✔️ Recognize and eliminate harmful substances inside the body. ✔️ Facing disease-causing changes inside the body such as cancer cells. 📌 Digestive System It is a series of organs that convert food into essential nutrients that are absorbed into the body and remove unused substances. The digestive system begins in the mouth and includes the esophagus, stomach, small intestine, large intestine, and rectum, and ends at the anus. ▪️ Digestive system parts: _the mouth _esophagus _stomach _ Small intestine _Intestine. the thick _rectum ▪️ The function of the digestive system ✔️ The function of the digestive system is to convert food into small parts, so that the body is able to absorb and use it as a source of energy, to help the body grow and repair damaged cells.
- 📌Rotation device: The circulatory system is known as the circulatory system, or the vascular system, and it is indicated that the circulatory system consists of the heart responsible for pumping blood to various parts of the body, and a network of blood vessels. ▪️ Rotational parts: _the heart _arteries _ veins _ Capillaries ▪️ The function of the circulatory system The following are the main functions of the circulatory system: ✔️ Providing the various cells of the body with oxygen and nutrients, including sugars, fats, vitamins, minerals, and amino acids. ✔️ Transferring the waste of vital processes and carbon dioxide to the organs specialized in their disposal. ✔️ Providing a quick way for the immune system to reach and eliminate pathogens. ✔️ Transfer of hormones secreted by the endocrine glands to the organs or tissues controlled by the endocrine glands. ✔️ Regulating body temperature, as the size of blood vessels close to the surface of the skin increases when the body temperature rises, allowing the excess heat to be disposed of. 📌The respiratory system: The respiratory system is one of the important organs in the human body, as it is responsible for the process of breathing, gas exchange, and helps to excrete carbon dioxide outside the body. ▪️ The parts of the respiratory system: _Mouth and nose _paranasal sinuses _pharynx _ Bronchi _ airways _lung ▪️ The function of the respiratory system The respiratory system performs many other functions in addition to the respiratory process, which are as follows: ✔️Helps speak and smell. ✔️ Moisturizes the air with the level of moisture the body needs. ✔️ Delivers oxygen to all cells of the body. ✔️ Protects the airway from irritants and harmful substances. ✔️Removes waste gases such as carbon dioxide when exhaled 📌The skeletal and muscular system: The skeletal and muscular system is related to the muscles and bones of the body, and it is indicated that the skeletal and muscular system enables the body to balance and helps it move. ▪️The parts of the skeletal and muscular system: _bones _cartilage _knuckles _ Muscles _ligaments _ strings ▪️ The function of the skeletal and muscular system: The main function of the skeletal and muscular system is to provide the body with balance and stability and help it move, in addition to that it performs the following functions: ✔️ The skeletal system plays an important role in the formation of blood, and in the storage of many minerals such as calcium. ✔️The muscular system stores most of the carbohydrates in the body in the form of glycogen
- The anatomy of the body is one of the branches of biology that is concerned with studying the structure and composition of the human body from the inside.
Vital Body Functions
Often the organs in the human body cooperate functionally to form integrated systems, The basic unit of the human body is the cell, and this cell constantly needs oxygen, energy and heat to accomplish its various functions
