Endoskeleton

An internal skeleton, it is made of bone and/or cartilage.

Endoskeleton Definition | GradesUp.gg
Endoskeleton Definition | GradesUp.gg

GradesUp

Learn While Playing The Best Video Games.

Using GradesUp:
Study: Students took a test on unknown facts in Biology and scored an average of 10%. After using GradesUp while playing games for 5 hours, their average score increased to over 70%.