There are 206 bones in the human body and two systems--the axialskeleton (trunk) and appendicular--(our limbs.)
excretory and reproductive systems
Frogs have four limbs, two hind legs and two forelegs.
Excretory and Reproductive
The main two are the skeletal system and the muscular system however, the muscles can't do anything without the nervous system and the cardiovascular system.
The nervous system and the endocrine system are the two major regulatory systems in the body.
The two coordination systems of the body are the nervous systems and the endocrine sytems, which enable all parts of the body to work together as one.
The Nervous System and the Endocrine System are the two body systems that regulate homeostasis.
Digestive and respitory systems
the respiratory and circulatory systems
there are way more than two, but i think you mean the endocrine and nervous systems
The nervous and endocrine systems are the two systems responsible for controlling behavior.