<span>The most primitive vertebrates whose reproductive pattern includes the amniotic eggs are the reptiles.
An amniotic egg is filled with amniote, which are these membranes that have fluid in them. They serve to protect the embryo and enable it to survive any harsh conditions that may harm it. These cells have protein shells as well as calcium that provide further protection.
</span>
Despite their frequency in the intertidal zone, in tide pools, sea urchins can be found at many different depths and in any habitats. They can also be found in nearly any ocean temperature. Sea urchins inhabit the polar seas as well as the warm tropics.
Explanation:
What happens during daytime is, oxygen that gets trapped between filaments of algae, moves them to the surface and during night as O2 is not produced, they slowly sink to lower depths, and you don't see them
Answer:
D. .................................
