Human Bio ATAR Year 11 - Excretion
System Exam Questions and Answers
Excretion - Correct Answers -The removal of metabolic waste from the body
Homeostasis - Correct Answers -Removing wastes allowing the body to maintain an
equilibrium within the body
Kidney - Correct Answers -filter blood and excretes nitrogenous wastes like urea, uric
acid and creatinine
Liver - Correct Answers -deamination and synthesis of urea
Lungs - Correct Answers -excretes CO2
Skin - Correct Answers -sweat glands secrete sweat (contains salts, urea and lactic
acid)
Urine composition - Correct Answers -95% water, 5% other solutes, no blood cells bc
too large to pass through glomerulus
effect of alcohol on urine - Correct Answers -increases urine output
effect on sleeping on urine - Correct Answers -kidney function slows at night, so less
urine produced and higher concentration in the morning
Liver functions - Correct Answers -Deamination, bile formation, blood glucose
regulation, fat conversion, plasma protein production, production of blood clotting
factors, storage, toxin and hormone breakdown and heat production
Deamination - Correct Answers -the stripping of nitrogen from amino acids
Deamination process step 1 - Correct Answers -1. removal of (-NH2) from the amino
acid
Deamination process step 2 - Correct Answers -2. The amino group is converted to
ammonia
Deamination process step 3 - Correct Answers -3. As ammonia is toxic to the body, it is
quickly converted to urea
System Exam Questions and Answers
Excretion - Correct Answers -The removal of metabolic waste from the body
Homeostasis - Correct Answers -Removing wastes allowing the body to maintain an
equilibrium within the body
Kidney - Correct Answers -filter blood and excretes nitrogenous wastes like urea, uric
acid and creatinine
Liver - Correct Answers -deamination and synthesis of urea
Lungs - Correct Answers -excretes CO2
Skin - Correct Answers -sweat glands secrete sweat (contains salts, urea and lactic
acid)
Urine composition - Correct Answers -95% water, 5% other solutes, no blood cells bc
too large to pass through glomerulus
effect of alcohol on urine - Correct Answers -increases urine output
effect on sleeping on urine - Correct Answers -kidney function slows at night, so less
urine produced and higher concentration in the morning
Liver functions - Correct Answers -Deamination, bile formation, blood glucose
regulation, fat conversion, plasma protein production, production of blood clotting
factors, storage, toxin and hormone breakdown and heat production
Deamination - Correct Answers -the stripping of nitrogen from amino acids
Deamination process step 1 - Correct Answers -1. removal of (-NH2) from the amino
acid
Deamination process step 2 - Correct Answers -2. The amino group is converted to
ammonia
Deamination process step 3 - Correct Answers -3. As ammonia is toxic to the body, it is
quickly converted to urea
