In Marine Sticklebacks, the Pitx1 Gene Is ____, but in Freshwater

question 39

Multiple Choice

In marine sticklebacks, the Pitx1 gene is ____, but in freshwater sticklebacks, the Pitx1 gene is ____.

• A) not expressed in fin buds of the pelvic region and spines are present; expressed and spines are absent
• B) not expressed in fin buds of the pelvic region and spines are absent; expressed and spines are present
• C) expressed and spines are present; not expressed in fin buds in the pelvic region and spines are absent
• D) expressed and spines are absent; not expressed in fin buds in the pelvic region and spines are present
• E) present so spines develop; absent so spines do not develop

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Definitions:

Secondary Oocyte

An intermediate cell in human and animal oogenesis, resulting from the first meiotic division of the primary oocyte, ready for fertilization.

Gametes

Gametes are the reproductive cells (sperm in males and eggs in females) that contain half the genetic information of an organism and can combine to form a new organism.

Reproductive System

A biological system within an organism which works to facilitate reproduction, consisting of organs and structures that enable the production of offspring.

Gametes

Reproductive cells (sperm in males and eggs in females) that carry half the genetic information of an individual and can unite with another to form a new organism.