Wastes And removal Flashcards
Deamination
Removal of nitrogen groups in amino acids
What is the excretory system responsible for?
Maintaining water balance, ion concentrations and waste removal in vertebrate animals
Amino acids can form
Glucose and ammonia (nitrogenous waste
Ways of getting rid of waste
- NH3- (must remove huge amounts of water) eg. Fish
2. Urea- (It needs a lot less water) (requires energy to s it
What animals make uric acid
Reptiles and birds
Uris acid (limited water available)
- less toxic than urea or ammonia, and is INSOLUBLE
- requires twice as much energy t convert ammonia to Uris acid
Urea
- less toxic than ammonia
- requires energy t convert ammonia toured
- humans and most mammals
Ammonia (lots of water available)
Toxic
- can be converted to less toxic forms
Kidneys roles
- filter blood, remove wastes
- produce urine,
- excrete hormones, vitamins and excess salts
- maintain pH of blood
Structure of kidneys
Medulla: second layer of kidneys- NEPHRONS
Cortex: outer layer of kidney, contains glomerulus
What is the nephron made up of
Long slender tubes where urine is produced, made up of glomerulus, bowman s capsule and loop of Henle
Glomerulus
Capillary network where fluid is filtered from capillaries under high pressure
Bowmans capsule
Blood filtering unit surrounding the glomeruli, collects fluid for more selective processing
End up with water, glucose
Urine formation
- Filtration
Reabsorption
Secretion
Filtration
Occurs in bow and capsule
- blood pressure forces water and solutes (glucose, sodium, urea) from glomerus into bowmans capsule
- filtered because blood cells, large proteins and large solutes remain in the blood
Reabsorption
Occurs in tubular sections of the nephron
- proximal tube selectively reabsorption glucose, salts, ions by diffusion or active transport
- loops of Henle reabsorption much more water
Secretion
Occurs in the opposite direction to reabsorption
- material from blood, (ions, uric acid and foreign substances like some drugs) enter the filtrate
Urine
Is the fluid that is left after secretion
Where is urine stored
In the bladder
ADH
Antidiuretic Hormone. uses the collecting tubules to reabsorption more water,
- the amount of ADH I the body determines how much water is lost by the body
- if an organisms water output is more than water input, then dehydration can occur
Water inputs
Free water
Metabolic water (cellular respiration)
Food (seeds, plants
Water outputs
Urine Sweat Milk production Faeces Exhaled air