Excretory Systems Flashcards
What is the type of nitrogenous waste in animals correlated with?
Evolutionary history and habitat
What is excretion?
The removal from the body of the waste products of metabolic activity
Why is defecation not considered as a part of excretion?
Faeces are undigested food remnants and not metabolic waste products
What are the two key functions that an excretory system performs?
The removal of nitrogenous wastes
The removal of excess water
Why are nitrogenous wastes removed?
They may be toxic to the body in large concentrations
Why are excess waters removed?
To maintain a suitable osmolarity within the tissues and cells
What are nitrogenous wastes produced from?
The breakdown of nitrogen - containing compounds like amino acid
What do mammals eliminate their nitrogenous wastes as?
Urea
What do reptiles and birds eliminate their wastes as?
Uric acid
What do lungs remove?
Carbon dioxide
What do kidneys remove?
Nitrogenous wastes (urea) and excess water/salts
What does the skin remove?
Excess water salts
Why do we urinate?
It contains excess water and salts our body doesn’t need
How is urea made?
When amino acids are broken down into the liver
