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The Excretory System
The Excretory System
Pelvis
Functions:
It eliminates nonsolid wastes from the body
It regulates body fluids
It filters the blood supply to remove salts and other body wastes
It controls rate of RBC formation
It regulates blood pressure
It regulates absorption of calcium
The Excretory System
Lungs
Skin
Liver
Kidneys
Ureter
Urinary Bladder
Urethra
Major Organs
The Urinary System
Lungs – exhale carbon dioxide and water vapor
Skin – Sweat glands in skin release excess water and salts
Liver – removes hazardous chemicals from the blood. (Detoxification of blood)
Some proteins and other nitrogenous compounds are broken down in the
liver forming a compound called urea
Major Organs
KIDNEYSThe two kidneys are located near the spine in the middle of the back.
They are protected by lower ribs and covered by layers of fat.
The kidneys are fist-sized, bean-shaped structures
It is possible to function with only one kidney.
Major Parts:
KIDNEYSAt any given time, 20 % of blood is in the kidneys.
The body’s entire volume of blood is filtered every 45 minutes.
If one ceases to work, the other increases in size to handle the workload.
Without the kidneys, it would not take long before the body’s system would be poisoned by its own waste.
Major Parts:
Two Layers:Cortex (Outer Region)Medulla (Inner region)
Nephron – filtering units
They clean and rebalance the blood to produce urine.
There are approximately 1 million nephrons in each kidney
Renal Artery
Renal Vein
Parts of the Kidney
FunctionsIt filters blood in order to remove cellular waste products from the body.
It helps to maintain homeostasis by filtering the blood.
It helps to maintain electrolyte, pH, and fluid balances
URINE
Waste drains out of the kidneys in the form of urine.
Urine is about 95% water and 5% urea (protein from protein breakdown).
Fresh urine has no bacteria in it. It is quite clean (probably cleaner than our hands).
Waste Products
Waste Products
Urea – a nitrogenous waste produced in the liver from the breakdown of protein. It is the main component of urine
Uric acid – usually produced from breakdown of DNA or RNA
Creatinine – waste product of muscle action.
Waste Products
Parts of the Kidney
Pelvis
Papilla
Calyx
Parts of the Kidney
Parts of the Kidney
Parts of the KidneyThe principal function of the loop of Henle is the recovery of water and sodium chloride from the urine.This is how the body’s water is conserved and howHomeostasis is maintained
Parts of the Kidney
Ureters – are tubes that carry urine from the pelvis of the kidneys to the urinary bladder.
Urinary Bladder – temporarily stores urine until it is released from the body.
Urethra – is the tube that carries urine from the urinary bladder to the outside of the body.
The outer end of the urethra is controlled by a circular muscle called a sphincter.
Other Parts of the Urinary System
Digestive System
When you eat, the food you eat gets processed by your digestive system. The solid waste come out the anus, while the excretory system processes the liquid waste and releases it.
Circulatory System
The excretory system pays close attention to the circulatory system to maintain liquid levels balanced, and keep all liquids in the body free of toxics.
Excretory System in Relation with other Systems
Nervous System
It also works with the nervous system because when the bladder is filled with urine, it sends the nervous system a message that it is time to go the bathroom.
Endocrine System
The Endocrine system has adrenal glands that have chemical substances that allow the kidney to control body fluid levels in the body
Excretory System in Relation with other Systems
Musculoskeletal System
It protects the organs in order for these to function well. They work in concert with the urinary system to regulate the release of urine. The bladder is a muscle that can expand and contract as necessary to accommodate or expel urine.
Excretory System in Relation with other Systems
Kidney Stones
Definition: These are smaller sized deposits of calcium and can be seen in the nephrons. The stones could also increase or go down to urinary tract causing extreme pain. The stone may also get infected causing further set of complications
Causes: The main cause is change/increase in salt and mineral levels and that of other substances in urine. This may later on cause coagulation and increase size of stones. The other reason can be heredity.
Symptoms:•Vomiting or nausea•Painful urination•Frequent urination•Fever or chills•Bloody or smelly urine•Sharp pain of the back or the side
Treatments: Reduced size of stones tends to pass out of body without requiring any surgery. The treatment may consist of just taking lot of fluids so that the stones are washed down. In such cases, the fluid is collected for 24 hours continuously and examined in laboratory for presence of small stones. Painkillers may also be used for alleviation of pains for the patient.
Cystitis Definition: The inflammation of the bladder is known as cystitis. The bladder is the storage place for the urine until it is discharged by voluntary action of body. The urge to urinate is not an automatic action and hence bladder always has some quantity of urine. The bladder is the place where bacteria can grow easily leading to inflammation of bladder.
Causes: It may be due to reaction of some of medicines, bacterial infection, using catheter for long time in case of some diseases, undetected underlying diseases, and a result of radiation therapy.
Symptoms:•Pain or difficulty when urinating•Foul-smelling urine•Pain or soreness of abdomen•Cloudy urine•Blood in urine
Treatments: Cystitis is normally treated with antibiotics for bacteria. The removal of contributing causes can also form part of treatment.
