NOVA- Origins: How Life Began
what perecent of earths history where there life on the surface of earth that you would see in the naked eye.
10%
tiny microbes raised the level of oxygen from less that one percent to today's ---- percent
21
when was earth born
4.5 billion years ago
the brown goo that formed in Stanley miller's lab was what?
Amino Acid
what cataclysm occurred that eventually led to the moon's formation?
The planet the size of mars hit earthearth
Amino acid
are compounds that form molecules when carbon and other elements link together and are the building blocks of proteins or (peptides), cells- which are the vital ingredients of all living things.
multi-cellular life that we are most familiar with- animals, plants and their environment- was made possible by the slow, toilsome task of ----- to oxygenate the -----
bacteria, atmosphere
Snottites acidity (ph) is that of
battery acid
named after the ----- - ----- color of their cells these cyanobacteria use photosynthesis to collect energy from the sun. they secrete a sticky coating to shield them from ----- radiation.
blue- green, ultraviolet
all living things are made up what chemical elements
carbon, oxygen, hydrogen, nitrogen- four of the mos common elements in the universe
blue-green cells that use photosynthesis to collect energy from the sun? the sticky coating does what
cyanobacteria; protects from ultraviolet rays
scientists found creatures of all types thriving in underwater volcanoes
despite scalding temp. acid eruptions and total lack of sunlight
Hydrogen sulfed can be
extremely poisonous so the scientists were masks inside the cave
Heavy bombardment
for about the firs 600 billion years, comments and asteroids (300 miles across) pounded our planet- a time known as
Earth was was covered in what? and smothered in what?
lava and noxious gas
what do you see in a magnifying piece of space dust?
mineral, carbon, and 4.5 billion years old
with the protection of the ---- layer, life was able to diversify into more complex ----.
ozone, organisms
amino acids, combinations of carbon and other basic elements had fused together to form more complex molecules called
peptides
when the atmosphere was thicker and dominated by CO2 the earth had a ------- tinge and the ocean had an olive ---- color.
redish, green
Earth is a place that is ------ and ------ by life.
shaped and modeled
over time, ----- spread out across the -----. As a byproduct of photosynthesis the ancient bacteria formed a waste product:----
stromatolites, planet , oxygen
heavy bombardment had what impacts
the impacts vaporized oceans and melted it's crust
the young sun was ---- than it is today
weaker
where are some of the oldest rocks found on earth? how old are these rocks?
west Greenland 3.7- 3.9 billion years old