So carbon dioxide can diffuse from the leaf
I think a villain can be a protagonist because the hero is antagonist.
Natural selection provides the outline of an explanatory theory." Biologists consider it to be a scientific fact that evolution has occurred in that modern organisms differ from past forms, and evolution is still occurring with discernible differences between organisms and their descendants.
The third one is ze answer
Hello, Leah082656. There are many heated arguments over discussing stem cell research because of these two moral principals: the duty to prevent or alleviate suffering and the duty to respect the value of human life. In order to get embryonic stem cells, the embryo has to be destroyed. Although this is a huge controversial problem, by researching this could actually save and treat many other people. Some people are for it because it saves multiple people in the process, and some do not like this because it is killing an embryo. Whatever your stance is on this debate, these are the two sides that people debate over. I hope I helped!! Have a great day. :)