Answer:
attatch the images of the Petri dishes so we can further help in understanding this question
The answer is Spiral. Spiral does not represent a type of nebula. There are only 3 types of nebula : Reflection, Emission & Dark. Reflection Nebulaedoes not emit its own light. Instead, it scatters the blue light from a nearby cool star. Emission Nebulae emits own light. Glow very brightly, and are frequently the birthplace of stars. Dark Nebulae also called "absorption nebulae", they block light from brighter objects behind them and can only be seen as an outline in front of a bright nebula or field of stars.
The earthworm has a closed circulatory system, and there are 3 main vessels: <span>aortic arches, dorsal blood vessels, and ventral blood vessels.
aortic arches: It functions as the heart of the earthworm
dorsal blood vessels: Responsible to carry blood to the front of the body
ventral blood vessels: Responsible to carry blood to the back of the body
hope this helps</span>