The fibrous protein that gives skin its flexibility and helps skin regain its shape after being expanded is:

Elastin          

Explanation:

The elastin is defined as an extracellular matrix protein which lends to the elasticity and also resilience to the tissues such as the lungs, skin, arteries,  tendons, and the ligaments.

Elastin synthesized from precursor molecule named tropoelastin.

Elastin is the fibrous protein which gives the skin its flexibility and also helps the skin regain its shape.

halogen, any of the six nonmetallic elements that constitute group 17 (group viia) of the periodic table. the halogen elements are fluorine (f), chlorine (cl), bromine (br), iodine (i), astatine (at), and tennessine (ts).

they fuse to form they have half as many chromosomes as a somatic cell of the same individual. b