Two Groups of Tomatoes Were Grown Under Laboratory Conditions, One

question 34

Multiple Choice

Two groups of tomatoes were grown under laboratory conditions, one with humus added to the soil, and one a control without humus. The leaves of the plants grown without humus were yellowish (less green) compared with those of the plants grown in the humus-enriched soil. The best explanation for this difference is that ________.

• A) the healthy plants used the food in the decomposing leaves of the humus for energy to make chlorophyll
• B) the humus made the soil more loosely packed, so water penetrated more easily to the roots
• C) the humus contained minerals such as magnesium and iron, needed for the synthesis of chlorophyll
• D) the heat released by the decomposing leaves of the humus caused more rapid growth and chlorophyll synthesis

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Definitions:

Long Run

In economics, a period during which all factors of production and costs are variable, and firms can enter or exit the market.

Nonprice Competition

A marketing strategy in which businesses attempt to attract customers through methods other than lowering prices, such as product differentiation, quality, service, and advertising.

Pure Competition

A market setup defined by many small businesses, identical products, unrestricted entry and departure, and complete information transparency.

Long-Run Average

A concept referring to the time period in which all inputs can be adjusted by firms, relating to production costs and decisions.