Question

The Calvin cycle and the Krebs cycle are referred to as cycles of chemical reactions because they
occur inside organelles.
start over continually.
are part of the carbon cycle.
allow energy to flow in ecosystems.

Answer 1

"Start over continually."

Both are called cycles because their series of reactions regenerates the original starting molecule each turn (e.g., RuBP in the Calvin cycle, oxaloacetate in the Krebs cycle).