Why would human life have any different purpose than a single cell organism. Life lives and then dies. What living organisms do in between that varies, but they usually grow, sometimes reproduce etc.
To attribute any other purposes would suggest that there is some higher or outer consciousness.
I can choose a purpose to act on, but I have not found anything else that directs a purpose.

The meaning is the what ever you give it

The ONLY real purpose of LIFE is to live it as best you can because it IS the only one you ever get.

Whatever purpose we make of it

If the purpose of doing those things you say is to have life everlasting with the almighty. (You say God, so i asume you mean christians who are working toward heaven.) If the purpose of being what is interpreted as a good christian is to get into heaven, then the atheist is living only one shot, yeah? We're doing our best here on earth with one life because it's all we got. (In my opinion)

They just spell it wrong, the main purpose of human life is not to make gods happy, its to make dogs happy.

It is what one makes of what is meaningful to them. I think the question should be rephrased as "What is the meaning of your life?"

The purpose of life is to be happy. What makes me happy is making others happy.

to live in the moment as best you can....there is no second time around so enjoy everything, learn as much as you can, make others' lives better and pave the way for future generations to have their chance at the same things...when you are done, hopefully, you enriched the life of at least one person who will do the same for another...

I don’t think that’s what most people who believe in god would say. Regardless, I’m with the Dalai Lama on the purpose of life — to be happy and to make others happy.