Which term refers to the silky threads mollusks secrete for attachment?

Which term refers to the silky threads mollusks secrete for attachment?

• A. Ear
• B. Muscle
• C. Sacs
• D. Byssus

Answer: (D)

The concept being tested is terminology for the attachment mechanism mollusks use. The term byssus refers to the silky, protein-rich fibers secreted by the mollusk’s foot that attach the animal to rocks or other substrates. These threads are produced by a specialized gland and can be extended and retracted to anchor the animal in place, helping it withstand currents and waves. The other options don’t describe attachment fibers: the ear is a sensory organ, a muscle is tissue for movement, and sacs are general internal cavities. Byssus is the specific term for these attachment threads.

The concept being tested is terminology for the attachment mechanism mollusks use. The term byssus refers to the silky, protein-rich fibers secreted by the mollusk’s foot that attach the animal to rocks or other substrates. These threads are produced by a specialized gland and can be extended and retracted to anchor the animal in place, helping it withstand currents and waves. The other options don’t describe attachment fibers: the ear is a sensory organ, a muscle is tissue for movement, and sacs are general internal cavities. Byssus is the specific term for these attachment threads.