uarinary formation explaination
Answers
The kidneys filter unwanted substances from the blood and produce urine to excrete them. There are three main steps of urine formation: glomerular filtration, reabsorption, and secretion. These processes ensure that only waste and excess water are removed from the body
Explanation:
⊙ Uarinary Formation Explaination
⊙ Urine Formation
☆ Urine is the liquid waste product of the human body. It contains urea, uric acid, salts, water and other waste products that are the result of various metabolic processes occurring in the body. It is formed in the primary excretory organs– the kidneys. The structural and functional unit of the kidneys is called the nephrons. Millions of nephrons are involved in the process of urine formation.
⊙ The formation process occurs in 3 steps or phases:
☆ Glomerular Filtration
☆ Tubular Reabsorption
☆ Tubular Secretion
⊙ The anatomy of the nephron is important to understand the urine formation process. Each nephron is made up of two parts:
☆ Renal Corpuscle
☆ Renal Tubule
⊙ The renal corpuscle is divided into the glomerular capillaries or glomerulus and the Bowman’s capsule. It is in the renal corpuscle that the blood is filtered at high pressure. The arteriole that brings blood into the glomerulus is called the afferent arteriole whereas the artery that takes blood away from the glomerulus is known as the efferent arteriole.
Between these arterioles forms, a network of capillaries called the glomerular capillaries of the glomerulus. The Bowman’s capsule is a cup-shaped structure in which this glomerulus is located. The glomerulus along with the Bowman’s capsule achieve the filtration of blood to form urine. The renal tubule consists of :
☆ The proximal convoluted Tubule(PCT)
☆ The U-shaped Loop Of Henle
☆ The Distal Convoluted Tubule(DCT)
⊙ Once the blood is filtered in the renal corpuscle, the resultant fluid is called the glomerular filtrate. This glomerular filtrate now passes into the PCT. In the PCT, substances like NaCl, K+, water, glucose, and bicarbonate are reabsorbed into the filtrate whereas urea, creatinine, uric acid are added to the filtrate.
⊙ From the PCT, the filtrate enters the U-shaped Loop of Henle where reabsorption and secretion of water and various metabolites occurs. The filtrate then passes into the DCT. From the DCT, the filtrate passes into the collecting tubules, into the renal pelvis and the ureters as urine to be stored int he urinary bladder.
