Closed Quiz 1 Flashcards
What is a galaxy
Vast collections of stars, gas and, dust
What is a light year?
Distance light travels in one year (about 6 trillion miles)
What is the name of our galaxy and how big is it?
Milky Way and it’s fairly big (would take 100,000 years to cris our galaxy
Approximately how many stars make up our galaxy?
a few hundred billion
100-400 billion
How old is our solar system? How does that age compared to the age of the universe?
4.6 billion years old
Solar system is much younger than the universe (13.8 billion years old)
what are the six qualities that living things have?
ORDER: molecules not randomly distributed
REPRODUCTION: living organisms make copies of themselves (genetic)
GROWTH: living organisms grows & develop (plants)
ENERGY UTILIZATION: to reproduce, grow, & maintain order (sunlight)
RESPONSE TO ENVIRONMENT: movement due to changes in environmental conditions (sunflowers)
EVOLUTIONARY ADAPTATION: gradual change in population of living organisms
What is evolution?
Gradual change, development, diversity in population of living organisms
*why earth has such great biodiversity
What is extremeophile?
What is it about extremeophiles that suggests that life might be widespread in the universe?
Living organisms that are adapted to conditions that would kill humans.
- Some can live in environments similar to those found on Mars,
-may be habitable in other planets in the universe,
What is it about life on earth that extremeophiles may not be widespread in the universe
There seems to be only one extreme that can survive?
What are the most important chemical elements for life on earth?
96% of life is made from four elements; oxygen carbon, hydrogen and nitrogen (all life on earth is based on carbon chemistry)
What was the big thing? When did it happen?
Big bang: theory— space, itself expanding, calling galaxies further away from each other. (Discovered by Edwin Hubble).
Happened about 13.8 billion years ago
What were the conditions like in the early universe?
In first moments, the universe was extremely hot and dense, but was expanding and cooling
What were the two main chemical elements produced just after the Big Bang?
Created hydrogen (~75%) and helium (~25%)
Where do the rest of the chemical elements come from?
When the universe was a few million years old clouds of hydrogen and helium gas could collapse to form the first stars
How is the chemical composition of the universe changing overtime
In today’s universe, when a star forms, a plantation system forms with it—heavy elements
Why would there have likely been no life in the universe even after it was a few hundred million years old
Without other elements, besides hydrogen and helium, it would have been difficult for life to begin