conserve vs use up

conserve

verb
  • To save for later use, sometimes by the use of a preservative. 

  • To protect an environment, heritage, etc. 

  • To remain unchanged during a process 

noun
  • Wilderness where human development is prohibited. 

  • A jam or thick syrup made from fruit. 

use up

verb
  • to consume, deplete or exhaust 

  • to take or occupy 

How often have the words conserve and use up occurred in a corpus of books? (source: Google Ngram Viewer )