step 5: the blood then goes through the of the to the it leaves the heart through the then the blood travels through the releasing to the cells for and absorbs the gas exchange occurring here between the oxygen and carbon dioxide molecules occurs in the of the organs. the blood then goes back to the side of the through the veins and will go through the again.

(in this step is where you can describe where your blood cell goes – whether it goes to the leg, arm, etc. – you can be creative.)

Embryonic stem cells are cells derived from an embryo. these cells can be used to create new tissues for patients suffering from certain illnesses and disorders. which statement best summarizes why the use of embryonic stem cells could be seen as unethical? a. some people consider embryos to possess rights equal to those of fully developed human beings. b. extracting stem cells from embryos is a very energy-intensive process, which consumes resources that could be used elsewhere. c. embryos are difficult to obtain, so the monetary cost of using them for research outweighs their benefit. d. the process of extracting stem cells from embryos generates biohazardous waste that cannot be safely disposed of.