The excretory system is responsible for removing the waste that is produced by our bodies. The excretory process within humans includes various organs and they work together to excrete the leftover. Urination, respiration, sweating and defecation all play roles in excretion of our body.

What Does the Excretory System Do?

In order to answer the question “how does the excretory system work”, we first need to figure out what excretory system is. In a narrow sense, the excretory system refers to the urinary system which removes waste from our bodies as urine. In a broader sense, however, the excretory system also involves the large intestine where wastes pass through as feces, the lungs which remove carbon dioxide, and the kidneys which eradicate liquid waste. Some liquid waste also evaporates from the skin, or it leaves through the lungs (which can be seen during cold days).

How Does the Excretory System Work?

Unlike other organ systems within our bodies, the excretory system is made up of a few different systems which spread throughout the body, working harmoniously to do its job. Below are details of these systems and how they work to excrete waste.

1. Urination

The urination system excretes urea from your body. Urea is produced when your body breaks down food rich in protein. It is then carried through the blood stream to the kidneys. The urea is filtered from the blood by miniscule filtering units within the kidney called nephrons. Urea, along with water and other waste substance, forms urine as it passes through the nephrons and down the renal tube.

From the kidney, the urine passes down two small tubes (called ureters) through to the bladder. Ureters are constantly tightening and relaxing in order to force the urine away from the kidney. Small amounts of urine are released into the bladder from the ureters. Circular muscles called sphincters help to keep the urine from leaking. Nerves in the bladder tell you when it’s time to empty.

2. Respiration

Since the broader definition of exretory system is not confined to urinary system, how does the excretory system work except letting the urine out? One of the answers is breathing out the gaseous wastes via respiration. The protein, fat and carbohydrates that we consume are eventually converted to glucose. This glucose is then greeted by oxygen in a chemical reaction, ‘cellular oxidation’ which produces the energy to drive all other bodily functions and chemical reactions of cells. The products of the reaction are carbon dioxide and water. The carbon dioxide is dissolved in the blood and carried to the lungs via the respiratory system where it is breathed out.

3. Sweating

Skin is the largest organ on the body. It protects the tissue and organs in the body and keeps the body cool through sweating. Sweating not only helps to lower body temperature, but also removes bacteria, dirt and dead skin cells from the pours, as well as excess water, salt and other wastes from the body.

4. Defecation

Defecation, also known as a bowel movement, is the act of excreting solid or semi-solid waste (feces) from the digestive tract. Fecal material is removed by muscular contractions in the walls of the colon, through the digestive tract, and to the rectum. The pressure inside the rectum eventually increases when the rectum becomes full, forcing the walls of the anal canal apart and allowing the fecal material to pass through. The rectum shortens as it disposes materials into the anal canal, propelling the feces out of the rectum with peristaltic waves.

How to Keep the Excretory System Healthy

After learning “how does the excretory system work”, it’s also important to know how to keep your excretory process healthy.

1. Hydration

If you don’t constantly replenish your water supply, your body reserves water for its most essential functions. Drinking plenty of water will flush your blood and remove toxins.

2. Exercise

When doing exercise, the increase of your heart rate and body temperature will cause your skin to sweat and release waste. Exercising also provides a highly oxygenated blood flow to the major organs of the excretory system.

3. Healthy Diet

Eating a varied diet packed with various sourced of nutrients will benefit the functioning of your excretory system. Processed foods often contain additives and preservatives that require more effort for your excretory system to process, so they are best avoided.

4. No Alcohol or Cigarettes

The toxins in alcohol and cigarettes gradually build up in your body as a burden for your excretory system to flush out. For this reason, it is best to avoid all harmful substances that offer no health or nutritious benefits.