EXCRETORY SYSTEM-KIDNEYS

-          The urinary system plays a vital part in maintaining homeostasis of water and electrolyte concentrations  within in the  body.

1.     If  Consists of

·         2 Kidneys -         Which secret urine

·         2 ureters    -        which convey the urine from the kidneys to the urinary bladder.

·         1 urinary bladder – where urine collects and is temporarily stored.

·         1 urethra – through which the urine is discharged from the urinary bladder to the exterior.

-          The kidneys produces the urine.

Ø  Metabolic waste  products

Ø  Nitrogenous compounds

Ø  Urea & uric acid

Ø  Excessions & some drugs.,

                                  KIDNEYS

1.           INTRODUCTION:- these are the excretory organs which are present in our body.

2.            SITUATION :It  lie on the posterior abdominal wall, one on each side of the vertabal column, behind the peritoneum and below the diaphragm.

3.            SHAPE:-“ Bean- Shaped”

4.            MEASUREMENT :- Lenth      -       11 cms

                                     Wide        –         6 cms

                                     Thickness-         3 cms

                                     Weight      -       150 gms

5.ORGANS ASSOCIATED WITH THE KIDNEYS:

      RIGHT KIDNEY:

            SUPERIORLY: The right adrenal gland

            ANTEROIRLY:The right lobe of the liver,the duodenum and the                                                 hepatic flexure of the colon.

       POSTERIORLY: the diaphragm,and muscles of the posterior                                                          abdominal wall.

   LEFT KIDNEY:

            SUPERIORLY:  The left adrenal gland

   ANTEROIRLY: the spleen,stomach,pancreas,jejunum and spleenic                                  flexure of the colon

POSTERIORLY: the diaphragm,and muscles of the posterior                                           abdominal wall.

6.PARTS:- 

                   1. Medulla

          2. Cortex

 3. Papillae of medulla,        

             4. Renal Pelvis.

-          Fibrous Capsule:- Surrounding the Kidney

-          Cortex – A  reddish- brown  layer of Issue

-          Medulla- the innermost layer, consisting of pale conical-shaped striations of  the renal pyramids.

RENAL PELVIS: it  is the funnel-shaped structure which  acts as a receptable for the urine formed by the kidney.

It has a no of distal branches called “Calyces”.

7.MICROSCOPIC  STRUCTURE OF THE KIDNEY

1.       The kidney is composed of about I million functional units, are we called it has “Nephron’s”a smaller number of collecting tubules.

2.       The  collecting tubules transport urine through the pyramids to the renal pelvis giving them their Stripped appearance.

3.       The tubules are supported by a small amount of connective tissues,

 it contains- Blood vessels, nerves & lymph vessels .

8.BLOOD SUPPLY:-

ARTERIAL SUPPLY:- RIGHT & LEFT RENAL ARTERIES

VENOUS DRIANAGE: RENAL VEIN BRANCH OF INFERIOR VENECAVA.

9. NERVE SUPPLY:-

SYMPATHETIC NERVE SUPPLY.

  PARA SYMPATHETIC NERVE SUPPLY.

10.FUNCTIONS OF THE KIDNEY:

1.Formation or Urine’s

1.   The kidneys from urine which passes through the ureters of the bladder for storage prior to excretion.

Composition of urine:

Water 96%

Urea 2%

Uric acid

Creatinine

Ammonia

Sodium                                   2 %

Potasium

Chlorides

Phosphates

Oxalates

2.   Kidneys are helps for the filtration .

3.   it helps to maintain the pH level (acid-base) balance  in the Body.

4.   It helps for secretion

5.   It helps to maintain water balance and urine output.

6.   Kidneys  are maintains the fluid electrolyte balance in the Body.

11.DISEASES OF THE KIDNEYS:

1.   GLOMERULONEPHRITIS – Inflammation of the Glomerulus

2.   ACUTE RENAL  FAILURE- sudden & severu reduction in the glomerular filtration rate & kidney function.

3.   RENAL CALCULI: Formation of stone in the Kidney.