Transcript Excretory System

Excretory System
Excretory System
• excretory system;
removes excess,
unnecessary or
dangerous materials from
an organism to help
maintain homeostasis.
• It is responsible for the
elimination of the waste
products of metabolism
as well as other liquid and
gaseous wastes.
Organ
Liver
Lungs
Function
Filters the blood, glycogen storage,
decomposition of red blood cells, plasma
protein synthesis, hormone production,
detoxification and bile production.
Filters the blood gasses removes
Carbon Dioxide and gains oxygen.
Skin
Gets rid of water, salts and urea
Kidney
Regulates electrolytes, blood pressure
and filters out wastes like urea and
ammonium. They also reabsorb water,
glucose, and amino acids. The kidneys
also produce hormones.
The Nephrons of the Kidney
Function: purification
and filtration of the
blood.
About one million
nephrons are in the
cortex of each kidney,
renal corpuscle
renal tubule
Glomerulus and Bowman’s
Capsule
• The Glomerulus: A ball of
capillaries, the main filter
located within the
Bowman's capsule
• Ultra-filtration: Blood
from the renal artery is
forced into the glomerulus
under high pressure.
Most of the liquid is
forced out of the
glomerulus into the
Bowman'scapsule.
• This does not work
properly in people who
have very low blood
pressure.
Proximal Convoluted Tube
• Proximal means "near to"
and convoluted means
"coiled up" so this is the
coiled up tube near to the
Bowman's capsule.
• Glucose is re-absorbed
from the ultra-filtrate and
put back into the blood. If
the glucose was not
absorbed it would end up
in your urine.
• This happens in people
who are suffering from
diabetes.
Loop of Henle
• Water is reabsorbed
• Kidney cells in this region
spend all their time
pumping sodium ions
This makes the medulla
very salty; you could say
that this is a region of
very low water
concentration
• Remember the definition
of osmosis
Collecting Duct
• Collecting ducts run
through the medulla
and are surrounded
by loops of Henlé
• The liquid in the
collecting ducts (ultrafiltrate) is turned into
urine as water and
salts are removed
Distal Convoluted Tubule
• Distal means "distant"
so it is at the other
end of the nephron
from the Bowman's
capsule
• This is where most of
the salts in the ultrafiltrate are reabsorbed.
Urinary System