Notes

Excretion:
---------
- The biological process through which harmful waste products are produced and excreted out of the body is known as metabolism.
- Kidney is the main excretory organ.
- The basic unit of kidney is nephrone.
- Excretory product means nitrogenous waste.
- Almost 90% of urine is composed of water.
- Other products are urea, creatanine, uric acid and different types of salt
- Urine's color becomes yellow due to a pigment known as Urochrome.
- A normal adult male expels around 1500 milliliter urine every day.
- The process through which water content and electrolytes are kept balanced in blood and osmosis is known as Osmoregulation.

Kidney:
-------
- Main excretory organ
- There are 2 kidneys in the back of each of the abdominal walls
- They are reddish brown and bean shaped
- The outer side of the kidney is convex and the inner side is concave having an indentation called Hilus.
- There are two ureters coming out of the two kidneys and they proceed downward and open up into the urinary bladder
- Nephrones in the kidney produce urine every second
- The urine produced in this are then transferred out by collecting tubules into the pelvis.

Nephrone:
---------
- The functional and secretory part of the uriniferon tubules of kidney is known as Nephrone
- There are 1 million nephrones in each kidney.
- Nephrones are composed of Renal Corpuscle, Renal tubules and a malphigian body.
- Nephrone -> Collecting Tubules -> Pelvis -> Ureter -> Urinary Bland -> Sensation of urination
- Each nephrone produces urine every second through a complex process. This urine is then carried by collected tubules and reaches the pelvis. The pelvis then carries it to the ureter. The ureter then collects the urine from the kidney and proceeds downwards to the urinary bland. After sometime, when enough urine is stored in the urinary bland, the sensation of urination is created.

Kidney Diseases and Remedy:
-------------------------
- Small stone like substances which are produced by the kidney are known as "Kidney Stones"
- Anyone can be attacked by this but it is seen more in males than in females.
- At first there is no remarkable problem from kidney stones, but after some time, kidney stones can pass into the urinary bladder and block urination. Fever and blood may come out of urine
- Kidney stones form due to excessive weight, infection in kidney, drinking insufficient water

Dialysis:
-------
- When kidney failure happens, the scientific process through which blood is purified is known as Dialysis.
- A dialysis machine attaches to the artery of the person and removes the blood through a tube. The tube then takes the collected blood and passes it through the dialysis machine and purifies the blood through Dialysis Fluid of the machine. The purified blood is then transferred back into the person through another tube connected to the vein of the person.
- This process is expensive and time consuming.

Kidney Transplantation:
--------------------
- Another alternative to kidney failure is kidney transplantation
- A person can live adequately with one kidney.
- A kidney from a healthy person can be transferred into the patient through a procedure. However, one must be aware of the tissue matching between the two people.
- There is every possibility of tissue matching between the relatives and family.
- Again, it is also possible to take a tissue matching kidney from a posthumous person.
- Here, posthumous means the brain dead person.