These stinging cell animalsuse what
to move their armlike parts?

Cnidarians uses arm-like parts called tentacles to sting.

Explanation:

Animals belonging to genus Cnidaria use arm-like structures called tentacles to sting. The cnidarians tentacles are present with specialized stinging cells called cnidocytes.

These cnidocytes are responsible for the stinging action which is done by the cnidocyte organelle called the nematocysts or the stingers.

Nemotocyts contain coiled thread or barb-like or hair-like structures which fires the toxin out while stinging.

The opening or the mouth-like parts on the tentacles contain numerous cnidocytes which releases toxin when the tentacles are touched by another organism or when the cnindarian touches its prey.

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure