Modern classification, otherwise known as taxonomy, was invented so as to have a single system used throughout the entire world in understanding different types of beings in existence. This way you avoid having different names for same things.
Each myofibril is attached at either end of the muscle fiber, when sarcomeres shorten, the muscle fiber Shortens
Mechanism :
Myofibrils are components of the animal skeletal muscles that are made up of sacromeres. They perform the muscular contraction and relaxation via the sliding filament model.
To produce motion, A cross-bridge forms between actin and the myosin heads triggering shortening of the sacromere. This shortening of the sacromere results in the contraction of the muscle fibers, which the net effect can be seen to be a shortening of the fibers.
To learn more about myofibril refer to : brainly.com/question/15461128
#SPJ4

¿What is the Kingdom Plantae?
It is one that is composed of multicellular, eukaryotic, autotrophic, anaerobic and immobile organisms whose reproduction is sexual or asexual.
They are classified in :-
I hope I've helped : )