New York State Cosmetology Practice Exam 2026 – The All-in-One Guide to Master Your Certification!

The correct answer highlights the fundamental types of chemical bonds that are significant in the structure and behavior of hair. Hydrogen bonds, salt bonds, and disulfide bonds play crucial roles in determining the strength and stability of hair fibers.

Hydrogen bonds are relatively weak and can easily be broken or reformed with changes in moisture and temperature. They are essential for the hair's flexibility and can influence styles that rely on wet-setting or drying.

Salt bonds, or ionic bonds, occur between positively and negatively charged groups in the hair's protein structure. These bonds contribute to the hair's overall strength and are also affected by pH changes, which can modify the hair's texture and shape.

Disulfide bonds are much stronger covalent bonds formed between cysteine amino acids in the hair. They are significant for the structural integrity of hair. Unlike hydrogen and salt bonds, disulfide bonds are not easily broken by heat or moisture. They are crucial during chemical processes such as perming and coloring, as breaking and re-forming these bonds can change the hair's shape and color.

In contrast, the other options mention types of bonds that are not relevant or do not play a significant role in hair structure. For example, covalent bonds are indeed strong bonds,