Question

What is a group of similar cells that perform a particular function called?

Answer 1

A group of similar cells organized to perform a particular function is a "tissue."

Explanation:

Like cells form a `"tissue"`
Example: cartilage made of chondrocytes
https://www.sciencedaily.com/terms/cartilage.htm

Different tissues form an organ
Example: lungs made of several kinds of tissue
https://alevelnotes.com/The-Lungs/169
(Scroll down to "The Structure of the Lungs"

Different organs form a system
Example: Many different organs make up the digestive system
https://www.hopkinsmedicine.org/healthlibrary/conditions/digestive_disorders/digestive_system_an_overview_85,P00380
(Scroll down a little)

Different systems combine to make up an organism

Like organisms form a species