If one system (digesting proteins with HCl in the stomach) doesn't work, then the next system addresses the problem, if it is functioning. If the HCl is present with zinc and B1 and B6, then the proteins are digested!! DO THE PINK PEE TEST! Pat. The beet test - Heal Thyself! Eat beets.
A game designer is a person who designs gameplay, conceiving and designing the rules and structure of a game. Many designers start their career in testing departments, other roles in game development or in classroom conditions, where mistakes by others can be seen first-hand.
Techopedia explains Level Design. During the early years of video games, a single programmer was responsible for every aspect of the game - there was no dedicated profession or discipline that catered to level design. Early games featured levels or stages with ascending difficulty rather than changing levels through story or plot progression.