GMO corn has been genetically altered to contain chemicals in it that will kill insects that eat the corn. What is bad is that the pollen also has the insect killing chemical. When the pollen gets blown from the corn to lets say milkweed, the monarch caterpillars that inadvertently come into contact with the blown pollen will die. So no Monarch Butterflies.
If honey bees come to collect the pollen for their hives, this will sicken and kill the bees. No honey.
No one knows the long lasting effects of GMOs, though some say people have been eating them since 1996 and that is evidence that there are no long lasting negative effects of GMOs. Since long term studies on rats that showed serious effects of GMO consumption have been discredited, and GMO foods are not labeled, it is hard to determine what the long lasting effects of GMOs are. There is evidence, though it is not accepted as valid by some, that people who are put on a non GMO diet have improved health.
It is opposed by some organizations and individuals because they are not convinced that the safety of the crops to the environment or human health has been proven, the regulatory process in the U.S. appears to have been influenced by those who develop and profit from the technology, etc.
Yes, but only some times some times they could be harmful
As far as is known, the government does not allow heavy metals in foods, but they allow them in other things, like vaccines, and they allow many additives and preservatives in foods that are harmful. Concerning GMOs, the government claims that they are not harmful or dangerous, and they are considered to be "substantially equivalent" to non GMOs by the FDA. There are various theories as to why the US government seems to promote GMOs, but none of the theories are substantiated.
There have been countries that have refused to import grains that contain GMOs, so it has resulted in negative effects on the GDP.
Non organic foods themselves would do no harm to you unless they contain harmful additives and/or preservatives, chemicals from synthetic pesticides that were sprayed on them, etc. It is also possible that non organic foods are genetically modified and the health effects of GMOs are not known, though there is some anecdotal evidence that they can have adverse health effects in animals and people.
People buy organic food because they do not want GMOs, artificial preservatives and additives, pesticides, and other harmful substances in their food.
There is no known information that indicates GMOs are easier to grown than non-GMOs.
GMOs are not caused, but produced. GMO is the abbreviation for Genetically Modified Organism. Basically, the process of genetic engineering removes a section of DNA from one organism, often a bacteria or virus, and inserts it into another organism, often a crop like corn or soybeans. The majority of genetically modified crops have been modified to withstand direct spraying of synthetic weed killers, or to produce a substance within the plant itself that kills insects when insects feed on the plant. The use of this technology is controversial, but to answer your question directly, many would say the "cause" is economical for the producers of the GMOs, since when they modify a crop genetically, the modified plants are considered unique organisms that can be (and are) patentable.
There is no evidence that GMOs have improved food production.
No, they do not. There are no laws that protect consumers if they do not want to eat GMOs. The consumers' only choice if they wish to avoid eating GMOs is to stop eating lots of foods that may contain GMOs.
Organic foods are good because they are produced without harmful chemicals and pesticides, GMOs, artificial flavors and preservatives. They are better for your body than non organic foods.