The urinary System is responsible for maintaining a stable internal environment for the body. Urinary System , system of organs that produces and excretes urine from the body. Urine is a transparent yellow fluid containing unwanted wastes, mostly excess water, salts, and nitrogen compounds. The major organs of the urinary system are the kidneys , a pair of bean-shaped organs that continuously filter substances from the blood and produce urine. Urine flows from the kidneys through two long, thin tubes called ureters. With the aid of gravity and wavelike contractions, the ureters transport the urine to the bladder, a muscular vessel. The normal adult bladder can store up to about 0.5 liter (1 pt) of urine, which it excretes through the tubel ike urethra.
Functions of the urinary system
Excretion metabolic waste products.
Maintaining the balance of tissue fluid and electrolyte.
Secretion of some substances.
Kidneys- The main organ
Urinary Bladder – Excretory ducts
The kidney is composed of several layers and is covered with a fibrous capsule, the renal capsule. The outer layer of the kidney is the cortex. It contains the major (upper) portion of the nephrons. The middle layer of the kidney is the medulla. It is composed of the triangular shaped pyramids and the renal columns. The pyramids contain the collecting tubules and loops of Henle, the lower portion of the nephrons. These tubules run nearly parallel to one another and give the pyramids a grain which leads to their points or papillae. The renal columns are regions between the pyramids in which blood vessels run to and from the cortex. The papilla of each pyramid projects into a funnel-shaped area known as the calyx. The calyces (plural of calyx) collect the urine released from the papillae and allow it to drain into a large area known as the renal pelvis and then into the ureter.
The position of the Kidney
Proximal tubule -
proximal convoluted tubule.
thick descending limb Henle’s loop.
thin descending & ascending limbs.
thick ascending limb Henle’s loop.
distal convoluted tubule
macula densa in DCT
Collecting tubule & duct
The kidneys remove urea from the blood through tiny filtering units called nephrons. Each nephron consists of a ball formed of small blood capillaries, called glomerulus, and a small tube called a renal tubule. Urea, together with water and other waste substances, forms the urine as it passes through the nephrons and down the renal tubules of the kidney.
Slender tubes that convey urine from the kidneys to the bladder.
Ureters enter the base of the bladder through the posterior wall.
This closes their distal ends as bladder pressure increases and prevents backflow of urine into the ureters.
Urinary Bladder -The bladder wall has three layers.
Transitional epithelial mucosa.
A thick muscular layer
A fibrous adventitia
The urinary bladder stores urine prior to micturition, the urethra expels urine from the bladder, the ureters bring urine to the bladder. But the function of the kidneys is NOT to make urine, it is to maintain homeostasis of the blood: excreting wastes, keeping nutrients, maintaining electrolytes, acid base balance, and other things.
NARROW LONG TUBES WITH EXPANDED UPPER END LOCATED INSIDE THI KIDNEY AND LINED WITH MUCOUS MEMBRANE .
APPROXIMATELY ¼ INCH IN DIAMETER AND
10-12 INCHES IN LENGTH
FUNCTION—TO DRANIN URINE FROM THE KIDNEYS TO THE BLADDER
Take a Closer look at the Urethra
Stages of Urine Production
Water and solutes across glomerular capillaries .
The removal of water and solutes from the filtrate.
Transport of solutes from the peritubular fluid into the tubular fluid .
An Overview of Urine Formation
When a loved one’s kidneys fail, you are also affected. You both face life changes because of kidney disease and its treatments. How you adapt to these changes depends on many things. I hope my presentation help give you a better understanding of the urinary system . The urinary System is responsible for maintaining a stable internal environment for the body. Urinary System , system of organs that produces and excretes urine from the body. Urine is a transparent yellow fluid containing unwanted wastes, mostly excess water, salts, and nitrogen compounds.