Sorry if this is a dumb question. So when you mow a lawn, the blades of grass are sheared and have a flat cross section. Yet when it comes time to mow again, they have tapered ends. How does this happen? And does human hair grow in the same way (thinking of shaving now)?
I’m not exactly sure what you mean by a flat cross section vs tapered ends. In either case though, hair doesn’t grow like grass since grass is a living plant while hair…isn’t. Grass can attempt to repair itself, what it can’t repair will turn brown and shrivel/fray (what you’ll often see a few days later). Whatever shape the end of your hair is in after being cut, is what it’s still going to look like weeks later, the only difference is that it may get worn down a bit, which would change what it looks like under a microscope, but that’s from it making physical contact with things, not from anything it can do to itself.
Nope.
Hair is dead, your follicle adds to the bottom of the hair and pushes it out to make the hair longer.
Grass is alive, it grows from the edges of the blade to get longer and wider. The cut end heals and begins to grow, back to the shape the blade is supposed to be.
Kind of like a tree, if you put a nail in a tree at 5’ high the nail will not go higher as the tree grows taller, the tree grows from the ends of the branches and the trunk just gets thicker year by year.
Hair can’t grow that way, because it’s only growing at the base.
On the other hand, you could get new hairs that start from the base and grow out, and those could have whatever sort of end hair naturally grows with.
Grass grows from the base, not the tip. That was a major evolutinary improvement since it gave grasses an edge over tip-growing plants,
If you see a sharp pointed blade that’s a new blade, Lawn grasses put out new blades quite often.