No, the word 'cell phone' is a singular, common, concrete, compound noun, a word for a thing.
The word 'your' is a possessive adjective, a type of pronoun; a word that is placed before a noun to show that that noun belongs to the person spoken to (you).
A possessive noun would be a noun in the possessive form placed before the noun (cell phone) to tell who the phone belongs to; for example, the teacher's cell phone or Jack's cell phone.
The possessive form for the noun woman is woman's.Example: The woman's cell phone kept interrupting our conversation.
The singular possessive form is: the cell membrane's purpose.
The possessive form of the proper noun Tammy is Tammy's.Example: I have Tammy's phone number.
The possessive form of the proper noun John is John's.Example: I have John's phone number.
The possessive form of the proper noun Betty is Betty's.Example: I have Betty's phone number.
The word "Lisa's" is the possessive form of the proper noun "Lisa".A possessive noun is formed by adding an apostrophe s ('s) to the end of the noun. The possessive form of the noun indicates that something in the sentence belongs to Lisa.Example:I have Lisa's phone number. (the phone number of Lisa)I went to school with Lisa's sister. (the sister of Lisa)
The possessive form of the singular, proper noun Scott is Scott's.Example: I have Scott's phone number.
The possessive form of the singular, proper noun Scott is Scott's.Example: I have Scott's phone number.
The possessive form of the proper noun Diaz is Diaz's.Example: Mr. Diaz's office is on the tenth floor.
The possessive singular noun is explorer's. The possessive plural noun is explorers'.
The possessive form for the noun coyote is coyote's.
The word 'my' is not a noun.The word 'my' is a type of pronoun called a possessive adjective.A possessive adjective is a word that takes the place of a possessive noun to describe another noun as belonging to someone or something.The possessive adjectives are: my, your, his, her, its, our, their.The possessive adjective 'my' describes a noun as belonging to the person speaking.Example: Just a minute, I left my phone on my desk.Note: The pronoun 'my' is capitalized only when it's the first word in a sentence.