Question

Animals belonging to Phylum Chordata are fundamentally characterised by the presence of structures noted as A, B, C and D. Identify them and select the correct option.

• A. A- Notochord, B- Nerve cord, C- Gill slits, D- Post-anal part
• B. A- Nerve cord, B- Notochord, C- Gill slits, D- Post-anal part
• C. A- Nerve cord, B- Notochord, C- Post-anal part, D- Gill slits
• D. A- Nerve cord, B- Gill slits, C- Notochord, D- Post-anal part

Answer 1

The correct option is B A- Nerve cord, B- Notochord, C- Gill slits, D- Post-anal part

The given figure shows the internal organisation of a hypothetical chordate. It possesses notochord (B) either during early embryonic stage or throughout life.The notochord lies ventral to nerve cord (A). It possesses a post anal tail (D) and paired pharyngeal gill slits (C).