Which term describes stacks of thylakoids?
a. chloroplasts
b. grana
c. stroma
d. ferredoxins

The right option is B. Grana

Grana are stacks of structures known as thylakoids. Thylakoids are sac like membrane-bound structures which are embedded within the chloroplast stroma of plants and green algae. The thylakoids is the site of the light reactions of photosynthesis and it functions by trapping the energy from sunlight during photosynthesis. The high surface area of the thylakoids maximizes the amount of photosynthesis that can take place.

the way that the mass of carbon can be conserved through cellular respiration is through a process/law called the law of conservation of mass which even tho it undergoes a process, mass is not be destroyed or changed

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

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