Urinary System

Urinary System

Published by: Nuru

Published date: 23 Jan 2022

Urinary System in Grade 7 HPE

Urinary System

The urinary system means the discharge of liquid waste along with the solvable toxins and unnecessary materials in the form of urine. It is the important part of our excretory system.

Functions of Urinary system are:

Urinary system helps to clear the excess liquid waste to maintain the balance of water in the body at the requirement level. In urinary system, we found a very important organ called kidney which helps in the circulation blood in the human body. There are many organs in the urinary system.

Organs of Urinary System:

Some of the organs in urinary system are as follow:

a. Kidney

A kidney is the most important part of the urinary system. There are two kidneys in the human body at the back of abdominal cavity on both sides of the backbone. They are like a bean in shape and are reddish brown in colour. There is two part of the kidney one is an external layer called Cortex and another is an internal layer called Medulla.

Each kidney weight is about 150g. Each kidney consists of a large number of tubules called nephrons which filtered the blood and urine. About 10 lakhs nephrons are there in each kidney. The purified blood is carried from the kidneys by the renal veins. The urine formed in the nephrons move downward the kidney by ureters and get collected in the urinary bladder. So, Nephrons are the structural and functional unit of the kidney.

b. Ureters

Ureters are the tubes by which urine transfer from the kidney to the bladder. There are two ureters which are connected to the kidney to the urinary bladder. Each ureter is about 25-30 cm long which functions is to carry urine from kidney to urinary bladder.

c. Urinary Bladder

The urinary bladder is a hollow muscular organ like sac, where urine is collected from the ureters. The urinary bladder starts outside by a tube called urethra. The urinary bladder has the capacity to hold up to500-700 ml urine but the human beings feel to urinate the urine when the bladder is about 300-400 ml filled. When the bladder is started to fill, we started to feel like doing urination.

d. Urethra

The urethra is a long tube that connects the urinary bladder to the urinary meatus for the extraction of liquid from the body. It is about 20-25 cm long in male which throws urine, sperm, and semen during the ejaculation and it is about 4 cm long in the female which throws the only urine. It is also called the reproductive part of the male and female.

Process of Urine formation are as follows:

The blood containing waste materials like an excess of water, urea, uric acid and other nitrogenous mixture etc enters in the kidney by a renal artery. The waste materials from the blood and the excess of water are absorbed by the nephrons and it converts them into the urine. Then the urine is transfer towards the ureters, then ureters collect the urine in the urinary bladder. When the urinary bladder get started to be filled, then human being started to feel for doing urination. The urine gets released through the urethra or reproductive part of the male and female.

The urine is in yellow in colour due to the presence of urobilin, which is formed by the breakdown of red blood cells. Human beings can produce about 900 ml to 1800 ml urine per day but depending upon the human being how much fluid they inhale that changes urination in decrease or increase.