Two Groups of Tomatoes Were Grown Under Laboratory Conditions, One

question 49

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 humus-enriched soil. The best explanation 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:

Single Unit

A single unit in the context of physiological studies refers to an individual neuron or muscle fiber that can be identified or recorded from.

Figure-Ground Perception

The ability to distinguish objects (figures) from background (ground) in visual images, a fundamental aspect of visual organization.

Connectedness

The state or feeling of being connected and having close relationships with others.

Closure

A psychological term referring to an individual's desire for a firm answer to a question and an aversion toward ambiguity.