The Evolutionary Innovation That First Appeared in Arthropods and Is

question 67

Multiple Choice

The evolutionary innovation that first appeared in arthropods and is characteristic of the most successful of all animal groups is that of

• A)bilateral symmetry.
• B)coelomic body architecture.
• C)jointed appendages.
• D)segmentation.

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Definitions:

Dizygotic Twins

Also known as fraternal twins, these are siblings born from two separate eggs fertilized by two separate sperm, sharing about 50% of their DNA, making them genetically similar to typical siblings.

Monozygotic

Referring to twins that originate from a single fertilized egg, resulting in individuals that are genetically identical.

Zygotes

The initial cell formed when a sperm cell and an egg cell merge, representing the first stage of development in many multicellular organisms.

Longitudinal Design

Research design in which one participant or group of participants is studied over a long period of time.