Anything in the environment that can cause a mutation is called as a mutagen.
Environmental mutagens include:
radiations, chemical, infectious agents, extreme heat.
The environment we live in has a real impact on whether we experience genetic mutations. The quality of water we drink and the air we breathe can actually effect the integrity of our DNA. Our bodies are designed to correct any mistakes, but dangers from the environment can increase our chances of ending up with a mutation.
The question above is about an experiment that was performed on eyes.
The experiment involves covering the left eyes of the experimental subject while the right eye is exposed to light at different distances and the correspondent size of the pupil measured.
In the graph given for the experiment, the largest decrease in the size of the pupil take place between 7 and 8 distances. At distance 7, the size of the pupil is 4mm while at distance 8, the size is 1mm, which means that, there is a decrease of 3mm in pupil size. This is the largest decrease on the graph.
I'm thinking it would be: surface mixed zone, transition zone, and deep zone
Copernicus and other astronomers before him thought that celestial bodies followed a circular orbital path.
Answer: circular - first choice
<span>we estimate that identical twins with Down syndrome occur at the rate of 1 or 2 in a million pregnancies and non-identical twins at the rate of 14/15 in a million. If the likelihood of having a twin or twins with Down syndrome is also linked to a family history of twins, to age or to assisted pregnancies, we presume these factors will play a part in increasing the risk for some individuals.</span>
