the excretory organs and their functions Flashcards
what plays a role in excretion
lungs ,skin,liver ,kidneys and bladder
through what process in faeces passed out through the anus
defaecation or egestion
what does faeces consist of
it consists mainly of the material that we have eaten , but not digested ,or could not be digested
why is the gut not considered as an excretory organ and the feaces not considered as an excretory waste
since feaces are not produced by metabolic activities of the body
what does the sweat glands of the skin secrete
mainly water ,some salts and a little urea ( which is a nitrogen containing or nitrogenous waste ) from the blood and from the sweat
what happens when we perspire
we lose sweat through the surface of the skin .in this way the skin excretes excess salts and urea
what are proteins digested into
amino acids
how is urea formed
when these amino acids are carried to the liver by blood vessels , excess amino acids are broken down to form urea
what is the process of the formation of urea called
de amination
where is the urea transported to
it is transported by the blood to the kidneys
how is urine formed
urea , together with other substances , form urine
what does the blood that passes through the kidneys contain
it contains metabolic waste substances such as urea and uric acid
how is urine formed
the kidneys filter these waste substances from the blood and use them together with water and salt to form urine
what stores the urine formed by the kidneys
it is stored by the bladder temporarily until it is passee out of the body by a process referred to as urination
what forms the urinary system
the kidney and the bladder together with tubes that transport urine , the ureters and urethra
