Which of the Following Combinations Correctly Matches a Phylum to Its

question 67

Multiple Choice

Which of the following combinations correctly matches a phylum to its description?

• A) Echinodermata-bilateral symmetry as a larva, water vascular system
• B) Nematoda-segmented worms, closed circulatory system
• C) Cnidaria-flatworms, gastrovascular cavity, acoelomate
• D) Platyhelminthes-radial symmetry, polyp and medusa body forms

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Definitions:

Motor Neuron

Cell that carries efferent information from the brain and spinal cord to make muscles contract.

Retrograde Messages

Signals that move backward across the synapse from the postsynaptic cell to the presynaptic cell, often involved in the modulation of neurotransmitter release.

Synapse Structure

The synapse structure refers to the complex architecture of the junction between two neurons, encompassing neurotransmitter release, reception, and signal processing areas.

Excitatory

Referring to neurotransmitters or neural pathways that increase the likelihood of a neuron firing an action potential, promoting neural activity.