A Nurse's Guide to the Human Body

When you study all of the different systems that work together inside the human body, you can quickly see that many things are happening at the same time to keep you growing, strong, and healthy. All of the systems inside the body have important jobs, and they all rely on the other systems to keep things running smoothly. If one system stops working properly, the other systems are often affected, so you need to see a nurse or doctor as soon as possible.

Cardiovascular/Circulatory System

The circulatory system includes the heart and blood vessels. The heart’s job is to pump blood through the body. With every beat of your heart, blood moves away from the heart in arteries and back toward it through veins. Scientists estimate that your heart beats about 100,000 times every day.

Digestive and Excretory Systems

The digestive and excretory systems work together to take in food, break it down, move nutrients throughout the body, and eliminate waste from the body. Digestion begins in the mouth as you chew your food. Muscles move the food down to the stomach, where muscles and stomach acid continue to break the food down further. When food enters the small intestine, enzymes break it down even more so nutrients can be transported throughout the body. As food moves into the large intestine, water and nutrients continued to be absorbed and waste products are pulled into the intestine. From here, waste moves through the large intestine to be eliminated from the body.

Endocrine System

Your body produces hormones that manage growth, tissue function, reproduction, mood, sleep, and more. The endocrine system includes the glands that produce hormones. These glands include the thyroid, parathyroid, pituitary gland, adrenal gland, pancreas, and reproductive glands.

Integumentary and Exocrine Systems

The integumentary system is an important system that includes your skin, hair, and fingernails. Although your skin isn’t very thick, it is your biggest organ. The skin has a very important job, which is to protect your body from things that could harm it. Your hair and nails help the skin with this job. Exocrine glands are in your skin. These glands excrete sweat. Your body excretes sweat to help keep it cool. Sweat can also contain waste products that your body doesn’t need.

Lymphatic and Immune Systems

The lymphatic system and the immune system work together in the body, sharing some organs. Your body relies on your immune system to fight off germs and bacteria that could make you sick. If any germs do get into the body, the immune system attacks them. The lymphatic system includes nodes and capillaries that move fluid throughout the body. This system is responsible for moving immune cells around and clearing out debris and other harmful things that could make you sick.

Muscular and Skeletal Systems

Working together, the muscular and skeletal systems have the important job of forming and supporting the body and enabling movement. These systems include all of your bones as well as joints, tendons, and cartilage that work together for movement. Along with these structural tissues, you also have muscles that are soft tissues, providing strength so you can do things like stand, walk, and run.

Nervous System

The job of the nervous system is to send signals throughout the body. Two separate systems make up the entire nervous system: the central and peripheral nervous systems. The central nervous system includes the brain and spinal cord. The peripheral nervous system includes the nerves that branch out from the central nervous system to all over the body.

Renal/Urinary System

The urinary system is also known as the renal system. This system is responsible for making, storing, and getting rid of fluid waste in the body. This fluid waste is called urine, and the kidneys make it by filtering out wastes and extra water that the body doesn’t need. From the kidneys, urine travels through tubes to the bladder. When the bladder fills, the urine exits the body through the urethra.

Reproductive System

The human reproductive system is in charge of making more humans. Together, the male and female reproductive systems work to produce babies. The male system produces sperm, and the female system produces eggs. If a sperm fertilizes an egg, the fertilized egg travels to the uterus, where it will grow into a baby inside a woman’s body.

Respiratory System

To stay alive, you have to keep breathing in oxygen. Oxygen is in the air. You might not think about it, but every day, you take about 20,000 breaths. Your respiratory system is in charge of breathing. You take in air through your nose or mouth, and it passes through your windpipe or trachea to your lungs. From the lungs, oxygen moves into your red blood cells, where the heart pumps it throughout your body.

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