Based on Their Body _______, Flatworms, Rotifers, and Ribbon Worms

question 14

Multiple Choice

Based on their body _______, flatworms, rotifers, and ribbon worms were not thought to be closely related. However, _______ showed that they are a _______ group.

• A) plans; the fossil record; monophyletic
• B) cavities; gene sequencing; monophyletic
• C) cavities; the fossil record; polyphyletic
• D) plans; gene sequencing; monophyletic
• E) cavities; gene sequencing; polyphyletic

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Definitions:

Medulla Oblongata

The lower brainstem region that regulates vital functions such as breathing, heart rate, and blood pressure.

Pyramids

Ancient monumental structures with a square or triangular base and sloping sides that converge at a point at the top, often used as tombs.

Germ Layer

One of the primary layers of cells (endoderm, mesoderm, ectoderm) in the early embryo that gives rise to all tissues and organs.

Ectoderm

The outermost layer of cells or tissue of an embryo in early development, giving rise to the outer layer of skin, central and peripheral nervous systems, eyes, inner ear, and many connective tissues.