1. Homeostatic mechanisms reflect both common ancestry and divergence due to adaptation in different environments.

2.  Circulatory systems reflect common ancestry.

3.  Before we go on, can you think of any??

4.  In order to carry on photosynthesis, green plants need a supply of carbon dioxide and a means of disposing of oxygen. In order to carry on cellular respiration, plant cells need oxygen and a means of disposing of carbon dioxide (just as animal cells do).  The exchange of oxygen and carbon dioxide in the leaf (as well as the loss of water vapor in transpiration) occurs through pores called stomata (singular = stoma).

7.  The breakdown of proteins and nucleic acids produces ammonia. Ammonia is very toxic to animals and requires access to large amounts of water to dilute the effects of the toxicity. Some animals convert ammonia into urea. Urea is relatively nontoxic and requires less water for excretion but does require energy for the conversion. Uric acid is relatively nontoxic and is excreted as a semisolid paste because it is insoluble in water. In general, the kinds of nitrogenous wastes excreted depend on an animal ′ s evolutionary history and habitat—especially the availability of water.

8.  Excretory systems in flatworms, earthworms and vertebrates  Osmoregulation in bacteria, fish and protists  Osmoregulation in aquatic and terrestrial plants  Circulatory systems in fish, amphibians and mammals  Thermoregulation in aquatic and terrestrial animals (countercurrent exchange mechanisms)

10.  http://www.slideshare.net/thelawofscience/t hermoregulation-13101660 http://www.slideshare.net/thelawofscience/t hermoregulation-13101660

11.  Osmoregulation is the active regulation of the osmotic pressure of an organism's fluids to maintain the homeostasis of the organism's water content; that is, it keeps the organism's fluids from becoming too diluted or too concentrated.  Organisms in aquatic and terrestrial environments must maintain the right concentration of solutes and amount of water in their body fluids; this involves excretion (getting rid of metabolic wastes and other substances such as hormones that would be toxic if allowed to accumulate in the blood) through organs such as the skin and the kidneys.

12.  Protists use contractile vacuoles to pump out water  Kidneys play a large role in animals  Fresh and salt water fish have different issues