Scientific Term Puzzle?

Question

What scientific term begins with the letter "Y"?

I am working on a puzzle (word search) and you need

to find one scientific term for every letter in the alphabet.

I'm almost done, I just need one for the letter Y. There's

no word bank, so it's much harder. Thank You.

I'm a freshman and I'm taking IPC.

Answer 1

I'm taking IPS too! lol, OK, let's see...

"Y-chromosome"

One of two s*x chromosomes in higher organisms that defines the gender of the adult. In almost all sexually reproducing organisms, the Y-chromosome defines male characteristics.

or

Yanai wave! (<--- idk what that means, but it's in my book, so there!)

Hope I helped =D