2 G1: Identify the ways in which a mammal gains and loses water Water LossUrine (Urea in water)FaecesSweatBreathingWater GainFoodDrinkChemical Reactions**Respiration = how the body releases energy from food.Oxygen + Food Carbon Dioxide + Water + Energy
3 The kidneys make sure that the amount of water gain equals the amount of water loss Water BalanceWater In = Water Out
4 G2: State that the kidneys are the main organs for regulating the water content in a mammal. This is calledOSMOREGULATIONwaterregulate/controlG3: Identify the position and state the functions of the kidney, renal arteries, renal veins, ureter and bladder.
5 NameFunctionKidneyFilter blood. Remove excess water and ureaRenal ArteriesSupply blood to the kidneysRenal VeinTake filtered blood away from the kidneysUreterTake urine (urea and water) from the kidneys to the bladderBladderStores urine until it is passed out of the body
6 G4: State that the kidneys work by filtration of blood and reabsorption of useful materials such as glucose.G5: State that urea is a waste product removed in the urine.
7 FILTRATIONAs blood flows through the kidneys, a lot of water and most of the substances dissolved in the plasma are filtered out. This includes urea, glucose, amino acids and salt.
8 RE-ABSORPTIONMany of these substances are needed by the body, so are RE-ABSORBED back into the blood.Urea and just the right amount of water that the body needs to lose are NOT re-absorbed. They pass out of the kidneys, down to the bladder and are excreted in the urine
9 C1: Explain the process of urine production using a simple diagram of the nephron.
11 Part of Nephron Function Glomerulus Kidney Tubule Collecting Duct Blood is filtered and collects in the Bowman’s CapsuleKidney TubuleUseful substances are re-absorbed (eg, glucose, amino acids) and pass back into the capillaries.Collecting DuctFinal re-absorption of water occurs here. The amount re-absorbed is controlled by ADH (anti-diuretic hormone).
12 Amino Acids Glycogen + Urea C2: State the source of urea in the body and describe how urea is transported to the kidneys.Urea is a poisonous nitrogenous (contains nitrogen) waste. It is made in the liver when surplus amino acids are broken down.Amino Acids Glycogen + UreaUseful carbohydrate stored in the liverUrea passes into the bloodstream and is transported to the kidneys where it is removed from the blood.
13 New term …… diuretic Opposite terms Don’t copy this!!!!!!!New term …… diureticA diuretic is a substance which causes an increase in the production of urine.Opposite termseg, clockwise/anti-clockwisesocial/anti-socialanti-viral
14 Diuretic Anti-diuretic A diuretic is a substance which causes an increase in the production of urine.Anti-diureticAn anti-diuretic will reduce the production of urine.
15 C3: Explain the role of ADH (anti-diuretic hormone) in the regulation of water balance = decrease production of urineAnti-diuretic hormone is released by the pituitary gland (part of the brain).Body can either produce lots of ADH or a little ADHLots of ADH= less urine
16 Scenario 1: Drank too much water Drinktoo muchBlood too diluteReleaseslittle ADHWater conc. in blood normalWater conc. in blood normalLow volume of water reabsorbed by kidneyLarge volume dilute urine to bladder
17 Scenario 2: Body has lost too much water sweatingBlood too concentratedReleaseslots ADHWater conc. in blood normalWater conc. in blood normalHigh volume of water reabsorbed by kidneySmall volume concentrated urine to bladder
18 G6: Explain the implications of damage to the kidneys by accidents or disease People can live with only one kidney, but if both kidneys become damaged, urea will build up and will eventually cause death if not treated.TreatmentDialysis (kidney machine)Kidney Transplant
19 C4: Describe the benefits and limitations of replacement and “artificial” kidneys.
20 C4: Describe the benefits and limitations of replacement and “artificial” kidneys. 1.Page 50 Biology Booklet2.Complete pages 43-513.Textbook Read/Revise/Take Notes/Answer Questions4.Last page of booklet – past paper questions/book