What Is an Index Fossil

question 16

Multiple Choice

What is an index fossil?

• A)An organism that existed for a vast period of time and is representative of an era
• B)An organisms that is restricted to one small, geographic setting
• C)A trace fossil that defines a colony of organisms
• D)An organism that was geographically widespread but limited to a short span of geologic time

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Definitions:

Common Bile Duct

The duct that conveys bile from the liver and the gallbladder to the duodenum.

Hepatic Portal

Referring to the hepatic portal vein, a blood vessel that carries blood from the gastrointestinal tract and spleen to the liver.

Hepatic Lobules

The functional units of the liver, hexagonal in shape, comprising a central vein surrounded by plates of liver cells (hepatocytes) involved in metabolic, detoxification, and secretory functions.

Digestive Organs

Structures involved in the process of digestion, including the stomach, intestines, liver, and pancreas.