Human Excretory System – An Overview

Introduction

The human excretory system is a sophisticated system. We get our nutrients from various places, which are then digested and utilized by our bodies. After metabolic processes, the body sifts out the beneficial and hazardous compounds. As we all know, toxin buildup may be dangerous, and the body eliminates all metabolic wastes through a process known as excretion.

Depending on their environment and feeding habits, various species use different excretion mechanisms. These may involve organs like the kidney, lungs, skin and eyes. Aquatic species, for example, produce excrement in the form of urea, whereas birds and insects emit uric acid. The primary excretory substance produced by humans is urea.

Let’s take a closer look at the human excretory system to learn more about the several organs that make up the excretory system, as well as the excretion process in humans.

Human Excretory System

• The process by which all metabolic wastes are eliminated from the body is known as excretion. Human excretion occurs in a succession of steps involving various body parts and internal organs
• In many species, diffusion is the most prevalent method of excretion. However, the human body has a unique mechanism in which several living activities (respiration, circulation, digestion, etc.) occur simultaneously. As a result, many waste products created in our bodies are in diverse forms, including carbon dioxide, water and nitrogen
• Chemicals and other hazardous substances from pharmaceuticals and hormonal products are also created in addition to these. Diffusion alone is insufficient to remove these wastes from our bodies. To remove waste products, we need more complicated and customized methods
• Both beneficial and toxic compounds can be found in the blood. As a result, we have kidneys that filter beneficial compounds from hazardous molecules by reabsorption
• A structural separation chamber called the nephron, filters the blood called to the kidney
• The capillaries of the kidneys filter the blood, and vital elements such as glucose, amino acids, salts and an appropriate quantity of water are reabsorbed before the blood returns to circulation
• Urine is formed by converting excess water and nitrogenous waste in humans. Urine is then transferred from the ureters to the urinary bladder. The Brain and Nervous System is in charge of the urinary bladder. The brain causes the mucous membrane to contract, and urine is excreted through the urethra, a urinary opening. The body maintains homeostasis for many factors in addition to temperature. For instance, the concentration of various ions in your blood must be kept steady, along with pH and glucose concentration

Organs of the Excretory System

Organs of the excretory system include:

Kidneys

Kidneys are bean-shaped organs safeguarded by the ribs and back muscles on each side of the spine. Each adult human kidney measures 10-12 cm in length, 5-7 cm in width and tips scales around 120-170 grams.

The inner surfaces of the kidneys are concave. The hilum, a depression on the inner circular cylinder of the kidney, is where the blood arteries, ureter, and nerves access the kidneys. The renal pelvis, a funnel-shaped area, located within the hilum, features many projections called calyces.

Henle’s loop 

Henle’s loop, which has a horizontal and vertical limb, is the next portion of the tubule. As a distal convoluted tubule, the climbing loop persists. Many nephrons’ proximal convoluted collecting ducts open into the proximal tubule.

• The Malpighian glomerulus, proximal convoluted tubule, ascending limb tubule, and distal convoluted tubule combine to form the cortical area of the kidney, whereas a loop of Henle makes up the medullary portion
• Cortical and juxtamedullary nephrons are the two kinds of nephrons. The Henle loop in the cortex is relatively short, extending only a few millimetres into the medulla. The Henle loop is exceedingly lengthy and goes deep into the medulla in juxtamedullary

Ureter

The ureter is a thin layer of tissue tubes that originate out of each kidney from the upper abdomen to the lower pelvic region of the body. It transports urine from the kidneys to the bladder. It is around 10 to 12 meters long and consists of muscular and fibrous coating — with a mucus membrane. 

 Urinary Bladder

It is a distensible sac-like structure that stores urine. Micturition or urinating is the process by which the urine bladder is emptied.

Urethra

This tube originates in the urinary bladder and aids in the removal of urine from the body. It serves as a common pathway for sperm and urination in males. Sphincter muscles protect the opening.

Explain the Human Excretory System

The following are the steps in the elimination process in humans:

Urine Production

The following stages are involved in the formation of urine in the nephrons:

• Filtration of the Glomerulus
• Reabsorption in the Tubules
• Secretion

Major Excretory Product in Humans

Organs of the human excretory system aid in eliminating nitrogenous wastes from the system.

• The kidney, uterus, urinary bladder, and urethra are the primary excretory organs
• The kidneys filter the blood, and the result is recovered in urine
• Urine travels from the ureter to the renal pelvis before being evacuated from the body. Micturition is the term for this
• Through excessive cleaning and filtration, the lungs also manage the osmolality of a mammal’s blood. Osmotic pressure is the term for this

Conclusion

The human excretory system is responsible for eliminating waste from the body. This system comprises capillary networks and specific structures that help with the excretory process. The kidneys and their functional unit, the nephron, are part of the human excretory system. Specialized hormones that govern the quantity of filtration within the nephron control the excretory action of the kidneys.