Question

1. stacks of thylakoids are called g----- (plural) or granum (singular)

Explanation:

In plant cell chloroplasts, thylakoids (membranous sacs involved in photosynthesis) are organized into stacks. The singular term for a stack of thylakoids is "Granum", and the plural form is "Grana". The question provides the singular "Granum" and asks for the plural (starting with "G----"), so the correct term is "Grana".

Answer:

Grana