Reference Terms
from Wikipedia, the free encyclopedia
Excretory system
The excretory system is the system of an organism's body that performs the function of excretion, the bodily process of discharging wastes. The Excretory system is responsible for the elimination of wastes produced by homeostasis. There are several parts of the body that are involved in this process, such as sweat glands, the liver, the lungs and the kidney system.
Every human has two kidneys. Each kidney is made up of three sections: the renal cortex, the renal medulla and the renal pelvis. The blood arrives at the kidney via the renal artery, which splits into many afferent arterioles. These arterioles go to the Bowman's Capsules of nephrons, where the wastes are taken out of the blood by pressure filtration. Peritubular capillaries also surround the nephron so substances can be taken in and out of the blood. The renal cortex is the outer layer of the kidney and the medulla is the inner layer of the kidney. The renal pelvis takes urine away from the kidney via the ureter. Both of the ureters lead the urine into the body's only urinary bladder, which expands and sends nerve impulses when full. From there, urine is expelled through the urethra and out of the body.
Related Stories
1
2
Health & Medicine News
November 16, 2025
Nov. 16, 2025 Penn State scientists identified a striking rise in melanoma across several Pennsylvania counties dominated by cropland and herbicide use. The elevated risk persisted even after factoring in sunlight, suggesting an environmental influence beyond the ...
Nov. 16, 2025 Researchers found that ancient hominids—including early humans—were exposed to lead throughout childhood, leaving chemical traces in fossil teeth. Experiments suggest this exposure may have driven genetic changes that strengthened ...
Nov. 16, 2025 A newly recognized set of T helper cells seems to guard against aging by eliminating harmful senescent cells. Their presence in supercentenarians suggests they may be a key to maintaining a healthier, age-balanced immune ...
Nov. 15, 2025 Researchers found that tau proteins don’t jump straight into forming Alzheimer’s-associated fibrils—first they assemble into soft, reversible clusters. When the clusters were dissolved, fibril growth was almost entirely suppressed. This ...
Nov. 15, 2025 Scientists identified a small molecule that interrupts a harmful protein pair linked to diabetic inflammation and tissue damage. The compound helped wounds heal faster and reduced organ stress in both Type 1 and Type 2 diabetes models. Unlike ...
Nov. 14, 2025 By reactivating a long-lost gene, researchers were able to lower uric acid levels and stop damaging fat accumulation in human liver models. The breakthrough hints at a future where gout and several metabolic diseases could be prevented at the ...
Nov. 14, 2025 Researchers uncovered how fatty molecules called ceramides trigger acute kidney injury by damaging the mitochondria that power kidney cells. By altering ceramide metabolism or using a new drug candidate, the team was able to protect mitochondrial ...
Nov. 14, 2025 Researchers have created a prediction method that comes startlingly close to real-world results. It works by aiming for strong alignment with actual values rather than simply reducing mistakes. Tests on medical and health data showed it often ...
Nov. 14, 2025 Scientists studying aging found that sensory inputs like touch and smell can cancel out the lifespan-boosting effects of dietary restriction by suppressing the key longevity gene fmo-2. When overactivated, the gene makes worms oddly indifferent to ...
Nov. 13, 2025 Exercise appears to spark a whole-body anti-aging cascade, and scientists have now mapped out how it happens—and how a simple oral compound can mimic it. By following volunteers through rest, intense workouts, and endurance training, researchers ...
Nov. 13, 2025 Ultra-endurance athletes can push their bodies to extraordinary extremes, but even they run into a hard biological wall. Researchers tracked ultra-runners, cyclists, and triathletes over weeks and months, discovering that no matter how intense the ...
Nov. 13, 2025 Researchers have uncovered surprising evidence that anxiety may be controlled not by neurons but by two dueling groups of immune cells inside the brain. These microglia act like biological pedals—one pushing anxiety forward and the other holding ...
Latest Headlines
updated 12:56 pm ET
Nov. 15, 2025 Scientists found that people who use both cannabis and tobacco show a distinct brain pattern tied to mood and stress regulation. Their scans revealed ...
Nov. 13, 2025 Smoking, vaping, or using both products significantly increases the likelihood of developing prediabetes and diabetes, and the risk is even higher among Hispanic, Black, and low-income groups. ...
Nov. 13, 2025 Researchers have designed a smart drug that hunts down and breaks a little-known RNA that cancer cells depend on. The drug recognizes a unique fold in the RNA and triggers the cell to destroy it. ...
Nov. 13, 2025 Scientists have discovered strange microscopic structures in the blood of people with Long COVID—clusters of tiny microclots tangled together with sticky immune webs known as neutrophil ...
Nov. 12, 2025 Colchicine, a cheap and widely used gout drug, may help prevent heart attacks and strokes in people with cardiovascular disease. Trials involving nearly 23,000 patients show meaningful reductions in ...
Nov. 12, 2025 Scientists have uncovered a new environmental culprit behind liver disease: tetrachloroethylene (PCE), a chemical used in dry cleaning and household products. The study found that people with PCE ...
Nov. 12, 2025 New research from the Technical University of Munich and Harvard Medical School reveals that popular GLP-1-based drugs, semaglutide (Ozempic) and tirzepatide (Mounjaro), not only promote weight loss ...
Nov. 12, 2025 Scientists in Seoul have uncovered 15 gut bacterial species linked to coronary artery disease, showing that microbes can influence heart health far beyond digestion. Their findings reveal how shifts ...
Nov. 12, 2025 GLP-1 drugs such as Ozempic and Wegovy may extend the lives of colon cancer patients, according to a major UC San Diego study. Patients on the medications had less than half the mortality rate of ...
Nov. 11, 2025 Texas A&M scientists have unlocked new potential for astatine-211, a rare and short-lived element, as a highly precise cancer-fighting isotope. Its alpha emissions destroy tumor cells while sparing ...