The Protostome Developmental Sequence Arose Just Once in Evolutionary History

question 21

Multiple Choice

The protostome developmental sequence arose just once in evolutionary history, resulting in two main subgroups-Lophotrochozoa and Ecdysozoa. What does this finding suggest?

• A) These two subgroups have a common ancestor that was a deuterostome.
• B) The protostomes are a polyphyletic group.
• C) Division of these two groups occurred after the protostome developmental sequence appeared.
• D) The lophotrochozoans are monophyletic.

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Definitions:

Skin Integrity

The condition of healthy and intact skin, which is essential for protecting against infection and disease.

Impaired Skin

Refers to the condition where the skin loses its integrity, leading to issues such as breaks, tears, or erosions.

Muscle Weakness

A reduction in the strength of one or more muscles, which can affect the ability to move and perform daily activities.

Hemostasis Phase

The first stage of wound healing, when the body acts to stop bleeding through clot formation and blood vessel constriction.