The Circulatory System of Cephalopods Is More Efficient Than That

question 21

Multiple Choice

The circulatory system of cephalopods is more efficient than that of other molluscs because

• A)it places the systemic circulation before the gills.
• B)it is a closed network of vessels.
• C)all blood is circulated through the gill filaments.
• D)accessory or brachial hearts increase blood pressure before blood flows through the gills.
• E)All of the choices are correct

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Definitions:

Protostomes

A group within the animal kingdom that includes organisms in which the mouth develops from the primary embryonic opening.

Radial Cleavage

A type of embryonic development in deuterostomes where the planes of cell division are either parallel or perpendicular to the vertical axis of the embryo, resulting in the cells being positioned directly above or beside each other.

Cleavage

Series of mitotic cell divisions, without growth, that converts the zygote to a multicellular blastula.

Meiotic Cell Divisions

A type of cell division that reduces the chromosome number by half, leading to the production of gametes in sexual reproduction.