Question

A helically coiled ammonite Turrilites is differentiated from externally resembling Gastropoda Turritella by

• A. apical angle
• B. number of whorls
• C. direction of coiling
• D. chambered shell

Hint:

In paleontology, paying attention to the direction of coiling can help differentiate between ammonites and gastropods. Ammonites typically coil in a more tightly wound helix.

Answer 1

The Correct Option is C

Step 1: Understanding the question.
Turrilites is an ammonite known for its helical coiling, while Turritella is a gastropod with a different type of coiling. The key difference lies in their coiling patterns.
Step 2: Analyzing the options.
(A) apical angle: This is not the key feature that differentiates these two genera.
(B) number of whorls: Both ammonites and gastropods may have multiple whorls, but this is not the defining characteristic.
(C) direction of coiling: Correct — The direction of coiling is the primary difference between the helical ammonite Turrilites and the gastropod Turritella.
(D) chambered shell: Both Turrilites and Turritella have chambered shells, so this does not differentiate them.
Step 3: Conclusion.
The correct answer is (C) direction of coiling, as this is the key feature that differentiates Turrilites from Turritella.