That's the description of the SOLID phase of matter.
Id say this is more of a biology question or even a psychology question , well its not a question at all but the endocrine system is a collection of glands that secrete hormones direct to the blood system (circulatory system) to be sent to the desired / target organ , an example of a gland could be the pituitary gland (located towards rear of brain)
Momentum is a vector quantity, and is always conserved. Whenever a collision occurs between two objects, the objects behave under the principle of conservation of momentum. Therefore, if an object moves in the direction opposite to its original direction after a collision, then this indicates that the momentum of the colliding object was greater than the object under consideration.