Question

How do hemichordates differ from chordates?

Answer 1

Hemichordates:

1. Animals of this phylum are deuterostomes and marine animals.
2. Hemichordate word means resembling half to the chordates.
3. They share some common characteristics with the chordates.
4. The common name for hemichordates is ‘acorn worms’.

Chordates:

1. This phylum consists of animals that bear a flexible rod that supports their dorsal side of the body, called the notochord.
2. This phylum includes tunicates, lancelets, and vertebrates.

Differences between hemichordates and chordates:

Hemichordates	Chordates
1. All the hemichordates are marine.	1. This phylum consists of both terrestrial and aquatic animals.
2. No notochord is present in them, instead, they possess a stomochord.	2. At some stage of their life, the notochord is present in them.
3. They have an open circulatory system.	3. They possess a closed circulatory system.
4. They do not have any post-anal tail.	4. They have a post-anal tail.
5. Examples- Balanoglossus, Saccloglossus, etc.	5. Examples- vertebrates, mammals, birds, fishes, humans, etc.