Resorption involves degrading chlorophyll to extract the majority of its nutrients. Nitrogen is found in chlorophyll and is often a limiting nutrient for plants because plants need large quantities of N to form amino acids, nucleic acids, proteins, and certain plant hormones. Once nitrogen and other nutrients have been extracted from chlorophyll, the nutrients will travel to other tissues of the plant. Resorption is what causes leaves in the fall to change colors. Carotenoids in the leaves are slower to degrade than chlorophyll, so autumn leaves appear yellow and orange.