* not completed

. Ontogeny is

development of the ear correct incorrect

the evolutionary history of a species or group correct incorrect

the study of cancer correct incorrect

the development of an individual organism correct incorrect

* not completed

. An example of a triploblast is

Hydra correct incorrect

sponges correct incorrect

Xenopus correct incorrect

a triploid plant correct incorrect

* not completed

. A key event in the evolution of the bilaterally symmetric triploblasts from the common ancestor of the triploblasts and the diploblasts would have been

the evolution of limbs. correct incorrect

the evolution of a nervous system. correct incorrect

the evolution of a gut. correct incorrect

the evolution of mesoderm. correct incorrect

* not completed

. Considering the ancient evolutionary split between protostomes and deuterostomes, which of the following pairs of animals is most closely related evolutionarily?

Caenorhabditis elegans and amphioxus correct incorrect

humans and Drosophila correct incorrect

sea urchins and humans correct incorrect

snails and starfish correct incorrect

* not completed

. In humans, the branchial arches are

embryonic gill slits, reflecting our evolution from fish correct incorrect

embryonic precursors to gills, which do not continue to develop in humans correct incorrect

embryonic precursors to structures in the face and neck correct incorrect

embryonic structures that develop into the ribs correct incorrect

* not completed

. How would you expect Hox genes to be expressed in centipedes, where all segments bear similar legs, when compared to insects?

The pattern of Hox gene expression would be the same as in insects, but the interpretation of segmental identity would have evolved correct incorrect

Leg-specifying Hox genes would be expressed in all the trunk segments correct incorrect

The Hox code is unlikely to be similar in centipedes and insects, and so the expression of Hox genes would be impossible to predict correct incorrect

Centipedes do not have or use Hox genes to specify identity along the anterior-posterior axis correct incorrect

* not completed

. Which is true?

limbs evolved from fins correct incorrect

ears evolved from jaws correct incorrect

bat wings evolved from bird wings correct incorrect

insects evolved from crustaceans correct incorrect

* not completed

. The rudimentary hindlimbs in some snakes may be attributable to evolutionary changes in

collagen proteins correct incorrect

apical ectodermal ridge formation correct incorrect

BMP signaling correct incorrect

Shh expression correct incorrect

* not completed

. The Hox gene complexes of mice and other mammals have evolved by

the splitting of one cluster into two correct incorrect

the duplication of a single ancestral Hox gene such as the one found in insects correct incorrect

the duplication of the ancestral cluster correct incorrect

the loss of three clusters from the ancestral condition of four clusters correct incorrect

* not completed

. The horse's hoof is homologous to human

fingers or toes correct incorrect

humerus correct incorrect

radius and ulna correct incorrect

wrist bones correct incorrect

* not completed

. Changes in the timing of developmental events is called

neoteny correct incorrect

ontogeny correct incorrect

heterochrony correct incorrect

phylogeny correct incorrect

* not completed

. The loss of pelvic spines during adaptive evolution in sticklebacks is based on

a mutation in the protein-coding region of the Pitx1 gene correct incorrect

a mutation in the protein-coding region of the Pitx2 gene correct incorrect

a mutation in the control region of the Pitx1 gene correct incorrect

the same mutation in Pitx1 in geographically distinct populations of spine-deficient fish correct incorrect

* not completed

. The evolutionary acquisition of sexual maturity by an animal while still in a larval stage is called

apoptosis correct incorrect

metamorphosis correct incorrect

neoteny correct incorrect

ontogeny correct incorrect

* not completed

. Which protein does the long-germ wasp Nasonia use for the initial patterning of the blastoderm

Bicoid correct incorrect

Engrailed correct incorrect

Krüppel correct incorrect

Orthodenticle correct incorrect

* not completed

. Which of the following statements regarding evolution is FALSE?

Multicellular organisms have arisen only once during evolution. correct incorrect

Changes in the control regions of genes are important in evolution. correct incorrect

Alterations in the timing of development are important in evolution. correct incorrect

Differences in Hox gene expression along the antero-posterior axis contribute to differences in arthropod body plan. correct incorrect