The First Multicellular Organisms Probably Arose About

question 57

Multiple Choice

The first multicellular organisms probably arose about

• A) 1.2 billion years ago.
• B) 500 million years ago.
• C) two billion years ago.
• D) 3.5 billion years ago.
• E) six billion years ago.

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Definitions:

Bryozoan Lineages

The evolutionary branches representing the diverse groups within the Bryozoa phylum, small aquatic invertebrate animals.

Modern Fauna

Refers to the animal species that inhabit the Earth during the current geological time period, known as the Holocene.

Carbon Dioxide

A colorless, odorless gas produced by burning carbon and organic compounds and by respiration. It is naturally present in the air and absorbed by plants in photosynthesis.

Marine Life

Organisms that inhabit the ocean and other saltwater environments, including fish, mammals, invertebrates, and plants.