In Some Molluscs,the Free-Swimming Larva Is a Trochophore While in Others,it

question 51

Multiple Choice

In some molluscs,the free-swimming larva is a trochophore while in others,it is a veliger with the beginnings of a foot,shell and mantle.What is the relationship of these molluscan juvenile stages?

• A)A veliger is found strictly in terrestrial molluscs
• B)The trochophore is considered ancestral and the veliger is a derived larval stage
• C)The two larval forms represent two early and distinct branches of molluscs
• D)The veliger is ancestral and the trochophore is a derived larval stage
• E)Only the cephalopods have the veliger stage;all other molluscs have a trochophore stage

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Definitions:

Backwards-counting Task

A cognitive exercise involving counting numbers in reverse order, often used to assess working memory or attentional control.

Working Memory

A mental framework with a constrained capacity, intended for the temporary retention of data to be processed.

Interference

A phenomenon where previously learned information hinders the ability to learn new information, often explored within the context of memory research.

Mnemonic Device

A memory aid or strategy that makes information easier to remember.