Sponges and Ctenophores Have Both Been Proposed as Basal Metazoans

question 11

Multiple Choice

Sponges and ctenophores have both been proposed as basal metazoans. Which of the following types of data support the idea that sponges are the basal group?

• A) sequences of cadherin genes, cleavage type, structure of collar cells, and bilateral symmetry of adults
• B) sequences of collagen genes, bilateral symmetry of adults, cleavage type, and fossil steroids
• C) fossil steroids, molecular clock, lack of tissues in sponges, and structure of collar cells
• D) structure of collar cells, bilateral symmetry of larvae, sequences of cadherin genes, and molecular clock

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Definitions:

Aden

A prefix used in medical terminology to denote related to glands.

Plasmapheresis

A medical procedure that involves the removal, treatment, and return or exchange of blood plasma from the circulation.

-apheresis

A medical procedure that involves removing a specific component of the blood, such as plasma, red cells, or white cells, and returning the remainder to the circulation.

Erythrocyte

A red blood cell that carries oxygen from the lungs to the body's tissues and returns carbon dioxide from the tissues back to the lungs.