Answer:The cell was no longer visible because the image wasn't centered before switching to higher objective of 40X.
Explanation:
While using microscopes, the image will approximately remain in focus if you adjust the focus during change of magnification. Therefore, there is need to always adjust the focus during change in magnification.
If object is not centered before switching to a higher power objective, object will not be visible.
To avoid this, center the object before switching to a higher power objective. This will help you find the object after switching the objective. And it is also important to use fine focus and not coarse focus.
Because they have so many children at once.
Gene flow is also called gene migration. Gene flow is the transfer of genetic material from one population to another. Gene flow can take place between two populations of the same species through migration, and is mediated by reproduction and vertical gene transfer from parent to offspring.
In the formation of an covalent bond, the electrons are shared between the atoms involved in the bonds. This way, the electron lies with both atoms, and is not completely transferred, meaning the there is no overall effect on charge.
Contrarily, in ionic bond formation, an electron is completely donated from one atom to another. The atom donating the electron is left with a positive charge due to loss of an electron, while the atom receiving the electron is left with a negative charge due to the gain of an electron.