Question

Which set of terms would most likely be used in a description of the nervous system of chordates?

• A. Brain, dorsal nerve cord, highly developed receptors
• B. Brain, fused ganglia, ventral nerve cord
• C. No brain, fused ganglia, tympanum
• D. No brain, nerve net, modified neurons

Answer 1

Answer: (A)

Brain, dorsal nerve cord, highly developed receptors

Chordates are a group of animals, such as fish, frogs, birds, dogs and humans. We all have central nervous systems made up of a brain and a dorsal (back) nerve cord. We all have highly developed receptors to detect changes in the environment for us to respond to.

Fused ganglia is a primitive brain found in earthworms, tympana is an external hearing structure in animals, such as frogs, insects, and mammals. Nerve nets are branched nerves without direction found in the Hydra.

Therefore, the correct answer is option A.