Chapter 11.3 Flashcards
What is excretion?
The removal from the body of the waste products of metabolic activity
What are the functions of the excretory system?
The removal of nitrogenous wastes which may be toxic in large concentrations, as well as the removal of excess water to maintain osmolarity in cells and tissues
How are nitrogenous wastes produced?
From the breakdown of nitrogen-containing compounds like amino acids and nucleotides
What does the type of nitrogenous base depend on in animals?
Based on evolutionary history of animal and habitat
How do aquatic animals eliminate their nitrogenous waste?
As ammonia
Why is ammonia preferably excreted in aquatic animals?
Due to its high water solubility, therefore can be easily flushed into the aquatic habitat
How do terrestrial animals eliminate their nitrogenous waste?
As urea which is less toxic so can be stored at high concentrations
How do reptiles and birds eliminate wastes?
As uric acid which is non toxic but requires more energy to make
How is water produced and consumed?
It is produced via condensation reactions and consumed via hydrolysis reactions
What is tissue viability dependent on?
Osmolarity of tissue
What are osmoconformers?
Maintain internal conditions that are equal to the osmolarity of their environment
What are osmoregulators?
Keep their body’s osmolarity constant, regardless of environmental conditions
Why is less energy required to maintain internal osmolarity in osmoconformers?
Due to the fact that the environment and cell share same conditions, then water movement will be minimized in and out of cell
Why is more energy required to maintain internal osmolarity in osmoregulators?
It ensures internal osmotic conditions are always tightly controlled
What is special about the excretory and digestive systems of insects?
They are connected to each other
What is the name of the circulating fluid system in insects?
The hemolymph
From where and how do the Malpighian tubules uptake nitrogenous wastes and water?
Malpighian Tubules branch off the intestinal tract of insect to absorb materials from hemolymph
What will the Malpighian tubules do when they have absorbed materials?
They will pass them to the gut where they will mix with digested food
What is reabsorbed by the hemolymph and what is excreted via anus?
Solutes, water and salts are reabsorbed while nitrogenous wastes as well as undigested food will be excreted
What are the different functions of the kidney?
-Water balancing system
-Blood filtration system
-Removes nitrogenous wastes
How does blood enter and exit the kidney?
Enters via the renal artery and exits via renal vein
What structures are responsible for the filtration of blood?
Nephrons and they produce urine
How is the urine transported and to where?
Transported via the ureter and will be stored in baldder