This Image Shows Tissue Layers of the Digestive Tract

question 21

Multiple Choice

This image shows tissue layers of the digestive tract.What does "2" represent?

• A)lumen
• B)muscularis externa
• C)submucosa
• D)mucosa (mucous membrane)
• E)serosa (mesentery)

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Definitions:

Self-interest

The pursuit of personal gain or advantage, whether economic, psychological, or physical.

Command System

A method of organizing an economy in which property resources are publicly owned and government uses central economic planning to direct and coordinate economic activities; socialism; communism. Compare with market system.

Central Planning

An economic system where the government or a central authority makes all decisions about the production and allocation of goods and services.

Economic Profits

The surplus generated when total revenues exceed the total costs (including both explicit and implicit costs) of production, reflecting a return beyond the normal profit level.