A: Morphological Phylogeny. B: Molecular Phylogeny

question 4

Multiple Choice

A: Morphological phylogeny.

B: Molecular phylogeny.
-What is true of the deuterostomes in the molecular phylogeny (B) that is not true in the traditional phylogeny (A) ?

• A) Deuterostomia is a clade.
• B) To maintain Deuterostomia as a clade, some phyla had to be removed from it.
• C) Deuterostomia now includes the Acoela.
• D) It is actually a grade, rather than a clade.
• E) It diverged from the rest of the Bilateria earlier than did the Acoela.

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Definitions:

Nervous System

The network of nerve cells and fibers that transmits nerve impulses between parts of the body, coordinating its actions and sensory information.

Endorphins

Natural chemicals in the body that interact with the brain's receptors to reduce pain and boost pleasure, resulting in a feeling of well-being.

Dendrite

The branched extensions of a neuron that receive signals from other neurons or sensory receptors.

Myelin

A fatty substance that forms a sheath around the axons of neurons, increasing the speed at which impulses propagate.