Excretion
General Information
Excretion: The removal of Harmful metabolic waste products
Excess water and salts taken in with food
Foreign substances (drugs, preservatives) taken into or absorbed
by body
Secretion: The release of useful substances formed in cells of the body
Eg. Enzymes (salivary amylase, Hormones = adrenaline)
Defaecation: The elimination of undigested or unabsorbed food food from the body
via the anus
Faeces consists of; substances not formed in body cells as result of
metabolic activity + never part of cells in cade of excretion or secretion
Functions of Excretory system
- Eliminates most of waste products of metabolism
The chemical process that occurs within a living
organism in order to maintain life
Retain molecules essential for normal body function
Elimination of waste products + reabsorption of essential materials
accomplished by nephrons - located in kidneys
- Regulation of body fluids (osmoregulation)
- Balance of pH & electrolyte composition of body fluids
- Production of hormones
Important in regulation of blood pressure
, Excretory Organ Metabolic waste products exerted
CO2
Lungs
Water vapour
Skin Mineral Salts
(sweat glands) Urea
Liver Bile pigments
Urea
Uric acid
Creatine
Kidneys
Ammonia
Excess water
Mineral Salts
Urea = main nitrogen containing substance in urine of
mammals
- Formed in liver
Lung : Oxygen - combining 2 ammonia molecules (NH3) +
Carbon dioxide molecule (CO2)
CO2 - When excess amino acids = deaminated
Water Vapour
Bile pigments = due to destruction of old red blood cells
Uric Acid comes from breakdown of DNA
- Can cause gout
Kidney : Waste Creatine from breakdown of creation phosphate in muscles
substances found in
bladder
Urea , Uric acid Liver : Toxic substances Skin = involved in excretion
Creatine , Ammonia Excess amino acids + secretion
Excess water , Glands Secrete oils
Mineral Salts Bile pigments Excrete sweat
General Information
Excretion: The removal of Harmful metabolic waste products
Excess water and salts taken in with food
Foreign substances (drugs, preservatives) taken into or absorbed
by body
Secretion: The release of useful substances formed in cells of the body
Eg. Enzymes (salivary amylase, Hormones = adrenaline)
Defaecation: The elimination of undigested or unabsorbed food food from the body
via the anus
Faeces consists of; substances not formed in body cells as result of
metabolic activity + never part of cells in cade of excretion or secretion
Functions of Excretory system
- Eliminates most of waste products of metabolism
The chemical process that occurs within a living
organism in order to maintain life
Retain molecules essential for normal body function
Elimination of waste products + reabsorption of essential materials
accomplished by nephrons - located in kidneys
- Regulation of body fluids (osmoregulation)
- Balance of pH & electrolyte composition of body fluids
- Production of hormones
Important in regulation of blood pressure
, Excretory Organ Metabolic waste products exerted
CO2
Lungs
Water vapour
Skin Mineral Salts
(sweat glands) Urea
Liver Bile pigments
Urea
Uric acid
Creatine
Kidneys
Ammonia
Excess water
Mineral Salts
Urea = main nitrogen containing substance in urine of
mammals
- Formed in liver
Lung : Oxygen - combining 2 ammonia molecules (NH3) +
Carbon dioxide molecule (CO2)
CO2 - When excess amino acids = deaminated
Water Vapour
Bile pigments = due to destruction of old red blood cells
Uric Acid comes from breakdown of DNA
- Can cause gout
Kidney : Waste Creatine from breakdown of creation phosphate in muscles
substances found in
bladder
Urea , Uric acid Liver : Toxic substances Skin = involved in excretion
Creatine , Ammonia Excess amino acids + secretion
Excess water , Glands Secrete oils
Mineral Salts Bile pigments Excrete sweat
