The celestial sphere is
a. a spherical galaxy, centered on the sun.
b. the star-sphere discovered by the greeks and other ancient civilizations which shows the physical location in space of the nearby stars.
b. the orb of the sun; a normal star.
d. the central spherical region of the milky way galaxy, dense with stars.
e. a useful illusion used to map the stars and other objects in the sky.

e. a useful illusion used to map the stars and other objects in the sky

Explanation:

A celestial sphere is a graphical representation whose purpose is to describe the different locations of objects in the sky. A Celestial Sphere depiction contains Earth's rotation axis, North Celestial Pole, South Celestial Pole and Celestial Equator.

within these regions are all the major types of biomes in the world. a biome is a community of animals and plants spreading over an extensive area with a relatively uniform climate. some diverse biomes represented in north america include desert, grassland, tundra, and coral reefs.