11.3
the kidneys & osmoregulation
Essential Ideas: All animals excrete nitrogenous waste products, and some animals also balance water and solute concentrations.
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Nature of Science: Curiosity about particular phenomena: investigations were carried out to determine how desert animals prevent water loss in their wastes.
UNDERSTANDINGS:
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11.3.U1 Animals are either osmoregulators or osmoconformers.
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11.3.U2 The Malpighian tubule system in insects and the kidney carry out osmoregulation and removal of nitrogenous waste.
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11.3.U3 The composition of blood in the renal artery is different from that in the renal vein.
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11.3.U4 The ultrastructure of the glomerulus and Bowman’s capsule facilitate ultrafiltration.
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11.3.U5 The proximal convoluted tubule selectively reabsorbs useful substances by active transport.
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11.3.U6 The loop of Henle maintains hypertonic conditions in the medulla.
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11.3.U7 ADH controls reabsorption of water in the collecting duct.
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11.3.U8 The length of the loop of Henle is positively correlated with the need for water conservation in animals.
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11.3.U9 The type of nitrogenous waste in animals is correlated with evolutionary history and habitat.
APPLICATIONS & SKILLS:
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Application: Consequences of dehydration and overhydration.
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Application: Treatment of kidney failure by haemodialysis or kidney transplant.
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Application: Blood cells, glucose, proteins, and drugs are detected in urinary tests.
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Skill: Drawing and labelling a diagram of the human kidney.
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Skill: Annotation of diagrams of the nephron.
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RESOURCES:
