Which of the Following Statements About the Evolution of Eye

question 39

Multiple Choice

Which of the following statements about the evolution of eye development in the ribbon worm (Lineus sanquineus) and planaria is false?

• A)Inactivating Pax6-related genes in planaria suppresses eyespot formation.
• B)Pax6-related genes are not expressed in regeneration experiments with planaria.
• C)A Pax6 homolog has been cloned in the ribbon worm.
• D)The Pax6 homolog gene in the ribbon worm is expressed at sites where eyespots will develop.
• E)Regeneration experiments involving expression of Pax6-related genes give different results in ribbon worm and planaria.

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Definitions:

Cranial Bones

The bones that form the skull, protecting the brain and supporting structures of the face.

Flat Bones

Bones with a thin, roughly parallel surface that provide protection for body organs and a base for muscular attachment. Examples include the skull, ribs, and scapulae.

Osteoclasts

Cells that break down bone tissue, playing an essential role in bone remodeling and calcium homeostasis.

Calcium Salts

Inorganic compounds found in bones and teeth, critical for maintaining their hardness and strength.