Question

(Two though provoking questions regarding “worms”)

1. Many of the organisms we have discussed thus far are small, some even microscopic. What might limit the size these organisms can attain?

2. How is a nervous system important for the diversity of ecological niches that flatworms can exploit?

Answer 1

Ans .1.On our planets different kinds of living beings are present .They can be as giant as elephant as small as bacteria.Microorganism are those which are not visible by naked eyes.To see them we need microscopes example bacteria .The microorganism are so minute because most of them are single celled , no tissue is present for differentiation .They show simple life cycle and processes.

Ans2 .Flatworm belong to phylum platyhelminths .They are simple flat and soft worms.Group of nerve cells controlling nervous system is  called ganglia.Parasitic flatworms have hook at their mouth to attach themselves to the host and consume digested food of the host .Hence, these don't need development of digestive and nervous system .Hence,the saved energy can be put into reproduction only .That is very much required for parasites.