Question

In Platyhelminthes________.
A. Nerve cords are present.
B. Nerve cords are absent.
C. Nerve nets are absent
D. None of the above

Answer 1

Hint:-Platyhelminthes are the flatworms that come under the phylum of invertebrates. These are both parasitic and non-segmented acoelomates. These are free living taxa. Here, according to the phyla classification, one of the types which is known as Platyhelminthes have no specialized respiratory and circulatory systems. Based on the nervous system it can be found and analyzed.

Complete Answer:- Platyhelminthes is hermaphroditic. Their body is softly covered with or without cilia. There are about 1300 species that come under the phylum Platyhelminthes. The following are the rank, biological name, kingdom that comes under the phylum Platyhelminthes. They are as follows:

HIGHER CLASSIFICATION	Platyzoa
BIOLOGICAL RANK	Phylum
SUBKINGDOM	Eumetazoa
SCIENTIFIC NAME	Platyhelminthes

They have some of the important characteristics:
- Platyhelminthes do not have respiratory tract.
- These are self-fertilized.
- Nerve cords are present here.
- There is the presence of parenchyma cells in their body cavity.
- There is a presence of flame cells.
- These flame cells help in osmoregulation and excretion.
- Platyhelminthes are classified into three types. They are as follows:
- Turbellaria
- Trematoda
- Cestoda
- Hooks and suckers are present in this phylum. Few organisms can cause severe diseases like snail fever. This is the most dangerous fever in the tropical countries. Taeniasis is another disease that is caused by tapeworms. Some of the examples for platyhelminthes includes:
- Dugesia
- Fasciola
- Taenia solium
So, it is clear that the correct answer is Option A.

Note:- This is the complex system with nerves all around the body. Their nervous system consists of two anterior ganglia, two nerve cords that are coining the length of the organism. These are interconnected by the transverse needs to form the ladder like structure. These have an organ level system of organization.