16. which of the following explanations accounts for the
formation of sunspots?
o a. the curvature of magnetic fields near the sun's equator creates
pockets in the photosphere that aren't warmed by convection.
b. magnetic field reversal causes portions of the sun to die slowly
over time, leaving dark marks.
o c. the movement of plasma is much faster on the poles than on the
sun's equator, and this creates pockets of intense heat.
od. volcanic eruptions are sustained by the photosphere, resulting in
hardened lava on the sun's surface.

A

Explanation:

Due to the inhibition of convection by the magnetic fields, these areas (usually occur in pairs corresponding to the two poles), the hot plasma from the sun’s interior doe not reach the surface of these areas hence creating local regions that are cooler than the rest of the photosphere. This cooler regions appear darker when observed with a telescope and are called sunspots.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

the generally accepted parts of modern cell theory include: all known living things are made up of one or more cells. all living cells arise from pre-existing cells by division. the cell is the fundamental unit of structure and function in all living organisms.