The Concept of Evolution Is Based on

question 17

Multiple Choice

The concept of evolution is based on

• A) any type of genetic variation within a population.
• B) all genetic variation in a population being equally successful in the same environment.
• C) survival and successful reproduction in organisms with favorable variations.
• D) parents with variations that pass these variations on to their offspring.

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Definitions:

Primitive Streak

Ectodermal ridge in the midline of the embryonic disk, from which arises the mesoderm by the inward and then lateral migration of cells.

Epiblast Cells

Cells in the early embryo that give rise to the tissues of the body.

Mesoderm

Middle of the three germ layers of an embryo.

Mesoderm

The middle layer of an embryo in early development, which gives rise to muscles, bones, and circulatory and excretory systems.