The tricuspid valve shuts. This prevents blood from flowing backward into the right atrium while the ventricle contracts. So, your answer will be the Tricuslid Valve. Hope I helped!
Answer:
This graph is showing how different rates of light intensity, environmental temperature, and Carbon dioxide affect the rate of photosynthesis. It looks like the greatest rate of photosynthesis has .13% Co2 at 30 degress celsius.
Explanation:
I was always taught that they y-axis is the dependent variable and going off that, all the other variables can be controlled and changed.
Axon: the messenger cell that carries the command to contract muscles.
Geologist Alfred Wegner noticed similar rocks & fossils remains were found on Continents which seemed to fit together. He called saw that it was the result of Continental drift and Pangea. Some evidence of the Drift was Rock evidence- Mountain ranges, Glacial scares, Location of coal deposits, ETC..
People couldn't image how the Earth could be millions of years ago. But the 1960's evidence would prove Continental Drift is TRUE and .. the story continues (as all good science!)
Continental drift means that continents move away from each other or separated.
