All animals and plants are made of cells. Animal cells and plant cells have features in common, such as a nucleus, cytoplasm, cell membrane, mitochondria and ribosomes. Plant cells also have a cell wall, and often have chloroplasts and a permanent vacuole.
Asker's rating. Report Abuse. You can stay outside for up to 2 years with a re-entry permit ...but you must keep a presence here ..home, bank account ..etc but for stays of over 6 months its best to get one a green card is for living here ...if you are not doing that you eill lose it. David Â· 6 years ago. Thumbs up. 2.
I have read from many sources thru internet and the answer is one year. Now, i have been in the situation wheares I stay outside the US. every 6 months and when my 6 month is up, I would fly back to the US. so my green card would be valid. I have done this about 3 times over the past 2 years and I will wait for one year this time before i go back there this March.