Which of These Molluscs Sometimes Do Not Have an Exterior

question 28

Multiple Choice

Which of these molluscs sometimes do not have an exterior shell?

• A) gastropods only
• B) bivalves only
• C) cephalopods only
• D) gastropods and cephalopods

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Definitions:

Cones

Photoreceptor cells in the retina of the eye that function best in relatively bright light and enable the perception of color.

Rods

Photoreceptor cells in the retina of the eye that are responsible for vision in low light conditions.

Nonspectral Colors

Colors that do not appear in the visible spectrum and are perceived through the combination of two or more wavelengths, such as pink or brown.

Receptor Cells

Specialized cells that respond to specific types of energy (e.g., light, sound) and convert it into neural activity.