Virus and viroids
Every cell is alive even root cells so yes
Endocytosis
no
DNA is found in every cell in every organism, even diseased cells.
The genes affect the whole organism because your genes are in your DNA and in every cell there is 23 pairs of chromosomes so you are what you are from your genes and DNA. Genes code for the proteins in your cells. Your proteins do nearly everything in your cells. Therefore the genes you have determine how you function at a cellular level. In terms of chromosomes, they are your DNA wrapped very tightly around protein clusters called histones.
A virus is an inert chemical, with no metabolic activity, when it is not inside a cell. It cannot function on its own. Whereas with a living cell you always have a metabolism, even if the cell is part of a parasitic organism.
Adipocyte
A virus is parasitic, it invades cells and uses the chemical content of the cell to reproduce more of itself, killing the cell in the process. When a virus invades an organism such as a person, the organism gets sick. Viral disease can be very serious, even fatal.
Cytoplasm moves because it has to transport all the materials inside the cell and in some protozoans it is even necessary for movement of whole cell such as Amoeba.
It could be a dinoflagellate, they have hard/shiny and even bio-luminescent cell walls
The subject you are talking about is probably genetic engineering. If you are able to take a gene from one organism and place it in another then you changed the DNA structure, which most likely can kill the plant, by possibly even creating a cancerous cell. But if the gene is transgenic enough the organism is a transgenic plant or animal.
There is no particular trend. For example a many-cells organism like humans have different cells than plants. (Cell walll, vacuole wise) While both differ from one-celled organisms like fungi, virus, and bacteria. Moreover, all the three are different. Fungi have a cell wall made of chitin while bacteria have a cell wall made of murein and a virus doesn't even gave a cell wall.