Osmoregulation and Excretion
Chap. 44
Overview:

Define Osmoregulation and Excretion
44.1 Osmoregulation balances the uptake and loss of water and solutes
 Discuss osmolarity (iso,hyper,hypo) (good , this should be review so you
should not have to spend too much time on it.
 Different types of osmoregulation
 Problems with osmosis
 Compare/contrast osmoconformer and osmoregulator (very important)
 Compare stenohaline and euryhaline
 Give example of osmoregulation (figure 44.2)
 Discuss differences between marine and freshwater animals
osmoregulation
 Anhydrobiosis
o Tardigrades
 Land animals
o Adaptations to cope with desiccation
 Fur
 Transport epithelium role in osmoregulation and excretion
44.2 An animal’s nitrogenous wastes reflect its phylogeny and habitat
 Compare/contrast differences between ammonia/urea/uric acid
o Production and elimination of ammonia.
o Aquatic species and ammonia details.
o Explain which animals use each process and why.
 Discuss adaptations to environment (evolution) YES!
44.3 Diverse excretory systems are variations on a tubular theme
 Excretory Processes
o Filtration/filtrate
o Selective reabsorption
o Secretion
 Excretory Systems
o Discuss protonephridium
 Figure 44.10
 Flame bulb
 Discuss excretory system of the following.
o Platyhelminthes
o Metanephridia
 Earthworms (annelids)
o Malpighan tubules
 Arthropods/insects
o Vertebrate Kidneys
 Evolution from segmented kidneys
44.4 Nephrons and associated blood vessels are the functional units of the mammalian
kidney (stress the structure/function relationship)
 Renal artery/renal vein
 Name parts of kidney associated urinary process
 Regions of the nephron
o Function of each
 Path of filtrate
 Discuss process of filtration, reabsorption, and secretion in mammalian
kidney and how they relate to each other.
 Compare/contrast cortical nephrons and juxtamedullary nephrons
o Discuss importance of juxtamedullary nephrons in birds and
mammals (urine adaptation).
 Figure 44.13:Mammalian excretory system (you might use the mammalian
system as the example that you use to explain the kidney)
o Explain each part
 Blood vessels
 Discuss figure 44.14 with numbered process (1-5)
44.5 The mammalian kidney’s ability to conserve water is a key terrestrial adaptation
 Solute Gradients and Water Conservation
o Two solute model (discuss bend)
 Loop of Henle
o Water conservation
o Countercurrent multiplier system (salt concentration) pg. 936
 Regulation of Kidney Function
o Nervous and hormonal controls
o Figure 44.16
o ADH
o JGA
o RAAS
o ANF
44.6 Diverse adaptations of the vertebrate kidney have evolved in different environments
 Briefly discuss mammals, birds, freshwater fishes, marine bony fishes.