An essential element categorized in elements that can alter the osmotic potential of a cell will be:

1. Nitrogen	2. Phosphorus
3. Molybdenum	4. Potassium

Identify the element that is not obtained by terrestrial plants primarily from soil?

A plant requires magnesium mainly for:

Which of the following elements is a constituent of vitamins such as thiamine, biotin and Coenzyme A?

The two elements required for splitting of water to liberate oxygen during photosynthesis are:
1. Manganese and Chlorine
2. Manganese and Boron
3. Copper and Chlorine
4. Molybdenum and Magnesium

The deficiency symptoms of which of the following tends to first appear in young tissues?

Any mineral ion concentration is considered toxic to plants if it reduces the dry weight of tissues by:

Symptoms of excess of manganese may actually be the deficiency symptoms of all the following except:

Absorption of elements by plants happens in two phases where:
1. The first phase is rapid into the apoplast and is passive and the second phase is slow into the symplast and is active.
2. The first phase is slow into the apoplast and is passive and the second phase is rapid into the symplast and is active.
3. The first phase is slow into the apoplast and is active and the second phase is rapid into the symplast and is passive.
4. The first phase is rapid into the apoplast and is active and the second phase is slow into the symplast and is passive.

In plants with nitrogen fixing bacteria (such as alfalfa or soybeans), the presence of oxygen will poison the bacterium. Which of the following acts as a natural defense against oxygen toxicity by scavenging free oxygen in these systems?