The human body is made up of many systems that work together to maintain life and health. This chapter of our exam biology e-book will explore 14 of these systems, giving you a comprehensive understanding of how the human body works.
1. Circulatory System
The circulatory system is responsible for transporting nutrients, oxygen, hormones and defense cells to all parts of the body. It is composed of the heart, blood vessels and blood. The heart works like a pump, pushing blood through the blood vessels.
2. Respiratory System
The respiratory system, composed of the lungs, trachea and other structures, is responsible for the exchange of gases. It allows us to inhale oxygen from the air, which is then transported to the body's cells, and to exhale carbon dioxide, a waste product of cellular metabolism.
3. Digestive System
The digestive system is made up of the mouth, esophagus, stomach, intestines, and other organs. It is responsible for breaking down food into nutrients that can be absorbed by the body for energy, growth and repair.
4. Excretory System
The excretory system, made up of the kidneys, ureters, bladder, and urethra, removes waste from the body. The kidneys filter the blood to remove unwanted substances, which are then excreted in the urine.
5. Nervous System
The nervous system, made up of the brain, spinal cord, and nerves, is the control center of the body. It takes input from the senses, processes that information, and sends messages to the body to respond appropriately.
6. Endocrine System
The endocrine system is made up of glands that produce and secrete hormones. These hormones regulate a variety of bodily functions, including growth, metabolism, sexual function and mood.
7. Muscular System
The muscular system is composed of skeletal, smooth, and cardiac muscles. It allows for body movement, maintains posture, and circulates blood throughout the body.
8. Skeletal System
The skeletal system, made up of bones, cartilage, ligaments, and tendons, provides a framework for the body, protects internal organs, and allows for movement. In addition, bones produce blood cells and store minerals.
9. Lymphatic System
The lymphatic system, made up of lymph vessels, lymph nodes, and other tissues, is responsible for defending the body against infection and disease. It also returns interstitial fluid to the bloodstream.
10. Immune System
The immune system protects the body against foreign invaders such as bacteria, viruses, and cancer cells. It is made up of a variety of cells and proteins that work together to defend the body.
11. Reproductive System
The reproductive system is responsible for reproduction. In men, it includes structures such as the testicles and the penis. In women, it includes the ovaries, fallopian tubes, uterus and vagina.
12. Integumentary System
The integumentary system, made up of skin, hair, and nails, protects the body from external damage, helps regulate body temperature, and allows for the sensation of touch, heat, and cold.
13. Urinary System
The urinary system, made up of the kidneys, ureters, bladder, and urethra, removes waste from the body through urine. It also helps regulate blood pressure and electrolyte balance in the body.
14. Sensory System
The sensory system is made up of a variety of sensory organs, including the eyes, ears, nose, tongue, and skin. It allows the body to sense and respond to the world around it.
Understanding how these systems work together to keep the human body functioning is fundamental to biology and the ENEM exam. We hope this chapter will help you better understand these systems and help you prepare for the test.
