The First Heart Sound (Lub) Is Produced by the Closing

question 28

Multiple Choice

The first heart sound (lub) is produced by the closing of the ____ and ____ valves.

• A) aortic semilunar; pulmonary semilunar
• B) right atrioventricular; aortic semilunar
• C) left atrioventricular; pulmonary semilunar
• D) right atrioventricular; left atrioventricular
• E) mitral; left atrioventricular

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Definitions:

Trading Practices

The activities and principles involved in buying, selling, and exchanging goods and services, both domestically and internationally.

Beaver Pelts

The skins of beavers, which were highly prized for their fur, playing a central role in the North American fur trade in the 17th and 18th centuries.

European Imports

Goods brought into the Americas or another region from European countries, which could include commodities like textiles, tools, luxury items, or technologies.

Massachusetts Bay

A region in the northeastern United States, centered around the bay that forms the central coastline of the state of Massachusetts, significant for its early colonial history and the founding of Boston.