That Science quiz thingy
Apr. 18th, 2006 11:18 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
pensnestFor anyone who had a go, the answers are below. (If you didn't have a go, the quiz was my LJ entry yesterday, so pray do.
nb The answers are exactly as I found them - if you need more information, I'm, um, not the best person to ask.
1. About 71 percent of the earth's surface is covered by water.
2. The single cells in the brain communicate through electrical and
chemical signals.
3. No. Dinosaurs went extinct at the end of the Cretaceous period, 65
million years ago. Modern humans did not appear until around 200,000
years ago.
4. Darwin's theory of species origination says that natural selection
chooses organisms that possess variable and heritable traits and that
are best suited for their environments.
5. A year, 365 days, is the time it takes for the earth to travel
around
the sun. A day, 24 hours, is the time it takes for the earth to spin
around once on its axis.
6. Solar radiation sunlight is scattered across the atmosphere by a
process called diffused sky radiation. The sky is blue because much
more
short-wave radiation -- blue light -- is scattered across the sky than
long-wave radiation -- red light.
7. Rainbows can be seen when there are water droplets in the air and
the
sun is shining. Sunlight, which contains all colors, is refracted, or
bent, off the droplets at different angles, splitting into its
different
colors of red, yellow, blue, etc.
8. Influenza viruses and others continually change over time, usually
by mutation. This change enables the virus to evade the immune system of
its host so that people are susceptible to influenza virus infection
throughout their lives. Bacteria mutate in the same way and can also
become resistant if over treated with antibiotics.
9. About 3.8 billion years; they're bacteria-like organisms.
10. Adding salt to snow or ice increases the number of molecules on
the ground surface and makes it harder for the water to freeze. Salt can
lower freezing temperatures on sidewalks to 15 degrees from 32
degrees.
Extra credit: Seasons occur because the earth is tilted at an angle of
23.5 degrees. At certain times of year the top half of the earth leans
to the sun and therefore gets more sun and has summer. When that same
half of the earth leans away from the sun it gets less light and has
winter.
nb The answers are exactly as I found them - if you need more information, I'm, um, not the best person to ask.
1. About 71 percent of the earth's surface is covered by water.
2. The single cells in the brain communicate through electrical and
chemical signals.
3. No. Dinosaurs went extinct at the end of the Cretaceous period, 65
million years ago. Modern humans did not appear until around 200,000
years ago.
4. Darwin's theory of species origination says that natural selection
chooses organisms that possess variable and heritable traits and that
are best suited for their environments.
5. A year, 365 days, is the time it takes for the earth to travel
around
the sun. A day, 24 hours, is the time it takes for the earth to spin
around once on its axis.
6. Solar radiation sunlight is scattered across the atmosphere by a
process called diffused sky radiation. The sky is blue because much
more
short-wave radiation -- blue light -- is scattered across the sky than
long-wave radiation -- red light.
7. Rainbows can be seen when there are water droplets in the air and
the
sun is shining. Sunlight, which contains all colors, is refracted, or
bent, off the droplets at different angles, splitting into its
different
colors of red, yellow, blue, etc.
8. Influenza viruses and others continually change over time, usually
by mutation. This change enables the virus to evade the immune system of
its host so that people are susceptible to influenza virus infection
throughout their lives. Bacteria mutate in the same way and can also
become resistant if over treated with antibiotics.
9. About 3.8 billion years; they're bacteria-like organisms.
10. Adding salt to snow or ice increases the number of molecules on
the ground surface and makes it harder for the water to freeze. Salt can
lower freezing temperatures on sidewalks to 15 degrees from 32
degrees.
Extra credit: Seasons occur because the earth is tilted at an angle of
23.5 degrees. At certain times of year the top half of the earth leans
to the sun and therefore gets more sun and has summer. When that same
half of the earth leans away from the sun it gets less light and has
winter.
