What is the difference between polar and nonpolar covalent bonds?

What must happen before a body cell can begin mitotic cell division

Which of the following units is not an official si unit? mole liter kilogram ampere

An animal cell loses the ability to convert energy stored in food to energy that the cell can use. which of the cell's organelles has stopped working? a.the mitochondria b.the nucleus c.the vacuoles d.the endoplasmic reticulum