True. A protein becomes functional only when it reaches its tertiary shape (3D). It is not necessary for the protein to reach the quaternary stage, but that is just a more complex functioning protein. It really is just two tertiary merged together. Example is red blood cells.
23. centromeres
25. mitosis
27. cancer
29. sister chromatid
31. tissues
Surface water changes into a gas and enters the atmosphere.
1.Gliding joint
2.Hinge joint
3.Pivot joint
<span>4.Ellipsoidal Joint</span>