When a Scientist Describes the "Body Plan" of a Phylum

question 30

Multiple Choice

When a scientist describes the "body plan" of a phylum, he or she is implying that ________.

• A) organisms direct their own evolution in order to maximise their success
• B) animals evolve according to a pre-ordained plan
• C) the body shapes we see now have been more successful than others in the past
• D) mutations have arisen that allow only some shapes to be produced

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Definitions:

Fetal

Pertains to a stage of human development inside the womb, from conception until birth.

Proximodistal Pattern

A pattern of physical growth and motor control that proceeds from the center of the body outward, in which torso and arm development precede that of the hands and fingers.

Prenatal Development

Prenatal development encompasses the process of growth and development within the womb, from conception to birth.

Upper Arm

The region of the human arm between the shoulder and the elbow, containing muscles like the biceps and triceps which are responsible for bending and stretching the arm.