Exam 37: Soil and Plant Nutrition

A group of 10 tomato plants are germinated and maintained in a large tray with no drainage. After several weeks they all begin to wilt and die despite repeated watering and fertilisation. The most likely cause of this die-off is ________.

Deficiency of calcium in plants causes ________.

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

Micronutrients are needed in very small amounts because

Rhizobia, actinomycetes, and cyanobacteria all share the common feature that they can ________.

Nitrogen-fixing bacteria and nitrifying bacteria convert atmospheric nitrogen into different compounds of nitrogen such as: (a) ammonium ion, (b) ammonia, (c) nitrate ion, and (d) nitrite ion. Which of the following is the correct sequence of formation of the nitrogen compounds?

Soil pH is an important factor that influences ________.

The specific relationship between a legume and its mutualistic Rhizobium strain probably depends on

What major benefits do plants and mycorrhizal fungi receive from their symbiotic relationship?

Soil erosion could be controlled by ________.

Which one of the following micronutrients plays a critical role as a component of chlorophyll?

The B horizon of soil has ________.

Why is nitrogen fixation an essential process?

How would you expect the root system of a plant grown by hydroponics to compare to the root system of a plant grown in soil? The root system of a plant grown by hydroponics would be ________.

There are several properties that are characteristic of a soil in which typical plants would grow well. Of the following, which would be the least conducive to plant growth?

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 ________.

Which of the following experiments is the best way to determine if an element is essential for plant growth?

Some of the problems associated with intensive irrigation include all of the following except

Which of the following soil minerals is most likely leached away during a hard rain?

Which of the following plants is classified as an epiphyte?