determine when two species diverged from each other. Explain how this was done.
Your essay should be at least 2 paragraphs long. Remember to write in complete sentences, using appropriate grammar, punctuation, and spelling. Be sure to cite any sources that you use.
|strong nuclear||strongest force||within a nucleus|
|electromagnetism||much weaker than strong nuclear||infinite|
|weak nuclear||much weaker than electromagnetism||0.1% the diameter of a proton|
One of the current goals in physics research is the unification of these four forces. Two have them have already been unified, electromagnetism and weak nuclear are together called the electroweak force. There are several theories allowing for
The theory of evolution states that organisms change over time. Evolution can mean large changes, such as when species split from each other, and small changes like the shape of a bird’s beak. While evolution can not be empirically proven, there is much fossil and DNA evidence to suggest that it is true.
The teacher’s domain video above states that humans and chimps had a common ancestor several million years ago. This timeline was calculated using molecular clocks. Certain genes undergo regular changes to the base pairs in their DNA, such as one gene that codes for a part of blood changes at a rate of .56 base pairs every billion years. When portions of DNA change at regular rates such as this they can be used as a type of clock to show how long ago species diverged by counting how many base pairs are different. If two species have only 2 base pairs different in the previously mentioned gene then they must have diverged from a common ancestor about 4 billion years ago.
If a person is riding in a car going 30 mi/hr and a second car goes by at 40 mi/hr in the same direction, the velocity of the second car is 10 mi/hr relative to our person in the first car or 40 mi/hr relative to the road. So what you are measuring relative to is very important.
m/s, regardless of the velocity of the source or the observer. Basically, nothing can move faster than light. This leads to the idea of time a fourth dimension and the development of space-time.
Click here to join Tim & Moby at BrainPop© as they explore relativity.
1) Click “Play Movie” to begin the movie. You can click “full screen movie”to watch the movie in a larger screen.
2) Check out the “Q&A” to review important ideas about relativity.
3) Want to learn some more? Go to “FYI” to learn cool facts about relativity.
4) How well do you understand relativity? Take the “Review Quiz” to find out. This is not an assessment – just practice! Your score is not recorded.
5) Close the window and return here to learn more!