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
Answer: b. The trochophore is considered ancestral and the veliger is a derived larval stage
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By evaluating the genome sequences of ____________, it is possible to compare sequences of two closely related species and determine the original sequence probably present in the common ancestor
Fill in the blanks with correct word
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A. hypoxic. B. oligotrophic. C. autotrophic. D. eutrophic.
You modify the primary sequence of an enzyme in a region that will be the active site when the protein
is properly folded. What is the predicted outcome of this change?
a. The enzyme will not properly bind to the substrate. b. The enzyme will not be able to bind an allosteric inhibitor. c. The enzyme will have an increased rate of activity. d. There will be no change in the enzyme's function. e. The enzyme will bind the substrate but not be able to release the products.