I believe that paleomagnetism was a key to determining that the seafloors were spreading since the paleomagnetism changes at certain geological intervals so that stripes of new rock with the youngest paleomagnetism would be right at the mid-ocean trenches and successively would be older the further they are from the trench, ie on either side of it, symmetrically.
Solution:
Phospholipid lipids is that contribute to the structure and function of the cell membrane.
Lipids all have one thing in common - they do not mix well with water. You can see this quite well if you try to combine oil and water. No matter how much or how hard you shake them together, they remain separated. This can be useful for organisms. For example, ducks produce lipids in their feathers, allowing the water to roll right off their backs and helping the ducks stay afloat.
Phospholipids are made up of two fatty acids (long chains of hydrogen and carbon molecules), which are attached to a glycerol 'head.' The glycerol molecule is also attached to a phosphate group, and this is the hydrophilic part of the molecule. The 'tail' ends of the fatty acid chains opposite the glycerol is the hydrophobic part of the molecule
The most important function for a phospholipid is to form the phospholipid bilayer. In this bilayer, the phospholipids are arranged so that all the hydrophillic heads are pointing outward and the hydrophobic tails are pointing inward. This arrangement comes about because the areas both outside and inside your cell are mostly water, so the hydrophobic tails are forced in.
THis is the required answer.
Three examples would be gamma rays (usually these rays are emitted from unstable isotopes and can be used in nuclear experiments and testing) ultraviolent rays that are emitted from the sun and can cause sunburn and even skin cancer because the rays mutate the DNA in the skin cells nucleus. And also X-Rays, microwaves, and radio waves, which is usually harmless because it isn’t enough radiation to mutate DNA in our cells
I hope this is what you wanted