Question

How do the hundreds of egg remain protected even if laid in open aquatic system?

Answer 1

because hard layer of outer shell of the egg.

Answer 2

Eggs laid out in the open aquatic system is a result of external fertilization. In external fertilization the female lays out the egg and the male the sperm in the water usually at the same time, after the sperm reaches the egg fertilization occurs. This fertilization in aquatic environment protects the eggs from drying out moreover, the eggs are held together with a jelly that also provides them protection.