In some species, adult structures can undergo dedifferentiation to form a relatively undifferentiated mass of cells that then redifferentiates during morphogenesis of the new structure. Such regeneration is characteristic of:

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#Question id: 24210

#Unit 1. Molecules and their Interaction Relevant to Biology

The human genome encodes four different hexokinases (I to IV), all of which catalyze the same reaction. If Two or more enzymes that catalyze the same reaction but are encoded by different genes are called to be

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#Question id: 15420

#Unit 5. Developmental Biology

signal from the inducing cell is necessary for initiating new gene expression in the responding cell. Without the inducing cell, the responding cell is not capable of differentiating in that particular way, phenomena known as:

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#Question id: 11565

#Unit 7. System Physiology – Animal

Portal blood vessels connect two capillary beds found in the ________.

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#Question id: 3391

#Unit 11. Evolution and Behavior

Which of the following statements is an example of genetic drift?

a. Allele g for fat production increases in a small population because birds with more body fat have higher survivorship in a harsh winter.

b. Random mutation increases the frequency of allele A in one population but not in another.

c. Allele R reaches a frequency of 1.0 because individuals with genotype rr are sterile.

d. Allele m is lost when a virus kills all but a few individuals and just by chance none of the survivors possess allele m

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#Question id: 14708

#Unit 5. Developmental Biology

Difference between gastrulation in Xenopus and sea urchin;

I. In Xenopus, formation of blastopore: mesoderm and endoderm move inside by involution over blastopore lip.

II. In sea urchin, formation of blastopore: mesodermal cells migrate into the interior; endoderm moves inside by invagination of the epithelial sheet.