1. Do you think life exists elsewhere in the universe besides planet Earth? Explain why or why not.
o Yes, yes I do, because people who are smarter than I am do. Why would we have SETI if people who are smarter than I am aren't thinking there's life elsewhere?
o I would expect chemistry to be the same everywhere. I would expect life to get started on other "Goldilocks" rocky planets with liquid water. Hey.
2. So what are the basic characteristics of life? List all the characteristics that you can think of.
Here's the GOSHARED mnemonic:
G is for Growth and development. Living things incorporate matter from the external environment, and use that matter for growing.
O is for organization. Living things are made from organized matter. Molecules -> organelles -> cells -> tissues -> organs -> organ systems -> individual organisms, for example.
S is sensitivity: stimulus-response. An organism senses something or other in its environment and responds to it.
H is for homeostasis. The organism tends to maintain an internal environment that will keep itself functioning.
A is for adaptation. A population evolves over time, but "e" didn't fit here for the GOSHARED mnemonic.
R is for reproduction.
E is for Energy use & metabolism. Living things use energy to make stuff and to do the things they do.
D is for DNA. Living Biota organisms use double-stranded DNA as their genetic material
Here's the MRS C GREN mnemonic:
Sensitivity (responds to environment)
3. Are any of these alive?
Lawnmower no, grass yes, tree yes
Candle no, flame no
Dead insect no, amber no, woodbark debris no
4. Do they exhibit characteristics of life? If so, which ones exhibit which characteristics?
Picking from the MRS C GREN mnemonic:
Grass MRS C GREN
Tree MRS C GREN
Dead insect: C
Woodbark debris: C
5. Why do space programs like NASA look for evidence of water on Mars?
None of those listed, but your teacher wants:
C. Earth life requires water.
Why that's not a great answer:
Software-based life does not require water.
6. How do you determine if the nanoparticles are alive?
B. Thaw the ice and see if they grow and reproduce
7. Based on your list from #2 is there enough evidence to say that the nanoparticles are alive? Why or why not?
Yes. They are alive.
o They're cellular (or an approximation of that)
o They have DNA and proteins, implying information storage, and functionality
o They reproduce (!!!). This implies metabolism somewhere.
o They are "sensitive" to oxygen and antibiotics, sort of
o They support and manufacture viruses (!!!)
8. Based on your list from #2 is there enough evidence to say the virus objects are alive? Why or why not?
Viruses are defined as nonliving. They are not alive. No metabolism = not alive.
HOWEVER: Their presence and reproduction is good evidence that something that IS alive is manufacturing them. There IS life in your thawed sample.
9. As chief advisor to the president, what would your recommendation be? Should he make the announcement that extra-terrestrial life has been discovered? Why or why not?
He should wait a few more days before making any announcement.
o The similarity of the nanoparticles and viruses to Earthly Biota life is good evidence for contamination of the sample by Earth Biota.
The science teams need time to determine if / when / how the contamination occurred.