A diatom has a cell wall made of . silica calcium chitin cellulose

Silica

Explanation:

A unique feature of diatom anatomy is that they are surrounded by a cell wall made of silica (hydrated silicon dioxide), called a frustule

Hope this helps!

A diatom has a cell wall made of silica.

Explanation:

Diatoms are eukaryotic phytoplankton cells known for their silica-containing cell walls (frustales), and are responsible for approximately 20% of total primary productivity globally. Diatom silica is a form of biogenic opal, containing oxygen isotopes and can be used in lacustrine and marine paleoenvironmental studies.

answer:

sequence 1- deletion

                  2- duplication

                  3- insertion

                  4- substitute

                  5- inversion