<span>maintaining a stable internal environment</span>
Explanation:
a control group does not. They should be identical in all other ways.
Well, obviously one would need to start off with a plan. After having an idea/blueprint of what your ideal treehouse will look like try finding some measurements for the wood (or whatever material you will use I won't judge) of course you better already have the length, width, and height of your treehouse. After that, you can get building; which could take days or even weeks depending on the house design and the amount of people you have to help out. Once that's done you can paint and decorate it all you want. (of course, to get it in the tree you might need a pulley to put it up there or build the bottom up on the tree.) And all your missing your ladder and that's it.
Crossing over is essential for the normal segregation of chromosomes during meiosis. Crossing over also accounts for genetic variation, because due to the swapping of genetic material during crossing over, the chromatids held together by the centromere are no longer identical.
I just found this on google