excretory system Flashcards
What are the KIDNEYS?
kidneys are the main excretory organs, they excrete wastes and excess water from the blood
what are the LUNGS?
Lungs remove carbon dioxide and small amounts of other gases (water vapour) from the body
what is the LIVER
The liver removes metabolic waste. It excreted water, salts, lipids, and removes harmful substances such as alcohol and drugs from the blood through detoxification.
What is the SKIN?
The skin removes excess heat and helps maintain the body temperature. It also excepted water, salts, and some urea in perspiration.
What are URETERS?
Ureters are tubes that carry wastes from the kidneys to the bladder
What is the BLADDER?
The bladder is the storage area for urine. Drainage is controlled by muscles called Sphincters.
How many mL’s can your bladder hold?
Up to 800 mL’s, but we become aware of the fluid at 250mL’s, and become uncomfortable at 500mL’s
What is the URETHRA?
The urethra is the passageway from the bladder to the opening from which urine exits the body
Each kidney consists of 3 layers:
1) Renal Cortex
2) Renal Medulla
3) Renal Pelvis
Renal Artery
Brings oxygen-rich blood TO the kidney
Renal Vein
Carried oxygen-rich blood AWAY from kidney
The wastes filtered by kidneys are made up of 3 nitrogen containing compounds, what are they?
1) Urea: produced in the liver, main component of urine
2) Uric Acid: produced from the breakdown of RNA and DNA
3) Creatinine
How can humans function with only one kidney?
If one kidney stops working, the other increases in size to handle the workload.
The Renal Cortex
Where blood is filtered
The Renal Medulla
Carry the filtrate (filtered blood) to the Pelvis through collecting ducts
The Renal Pelvis
A hollow cavity where urine accumulates and then drains into the ureter
What are Nephrons?
Nephrons are the functional units within the kidney that remove waste, while reabsorbing useful molecules and water
Where are nephrons found?
Within The Renal Cortex and The Renal Medulla
GLOMERULUS
A mass of thin-walled capillaries located in the cortex of the nephron
BOWMANS CAPSULE
A double-walled structure that encapsulates the glomerulus
Proximal Tubule
Leads from the Bowman’s capsule to the Loop Of Henle
Loop Of Henle
A long loop which extends to the medulla
Distal Tubule
Connects to the loop of Henle to the collecting duct
Collecting Duct
Passes urine on to the renal pelvis of the Kidney