20 terms


Which of the following describes the fate of most of the water taken up by a plant?
c. It is lost during transpiration.
Most of the dry weight of a plant is the result of uptake of
c. CO2 through stomata in leaves.
Organic molecules make up what percentage of the dry weight of a plant?
e. 96%
In hydroponic culture, what is the purpose of bubbling air into the solute?
b. to provide oxygen to root cells
When performing a mineral nutrition experiment, researchers use water from a glass still. Why is it not a good idea to use regular distilled water from a stainless steel still?
c. Metal ions dissolving off the steel may serve as micronutrients.
Which of the following essential nutrients does not have a role in photosynthesis, either as a structural component or in the synthesis of a component?
e. K
Which of the following is of least concern to a researcher in a mineral nutrition experiment?
d. ability of a laboratory balance to weigh very small quantities of chemicals
Which two elements make up more than 90% of the dry weight of plants?
d. oxygen and carbon
The bulk of a plant's dry weight is derived from
b. CO2.
What are the three main elements on which plant growth and development depend?
c. oxygen; carbon; hydrogen
A growing plant exhibits chlorosis of the leaves of the entire plant. The chlorosis is probably due to a deficiency of which of the following macronutrients?
c. nitrogen
Which of the following elements is incorrectly paired with its function in a plant?
e. sulfur—component of DNA; activates some enzymes
Reddish-purple coloring of leaves, especially along the margins of young leaves, is a typical symptom of deficiency of which element?
d. P
Which of the following best describes the general role of micronutrients in plants?
a. They are cofactors in enzymatic reactions.
Which of the following is not true of micronutrients in plants?
d. They are the essential elements of small size and molecular weight.
What is meant by the term chlorosis?
c. the yellowing of leaves due to decreased chlorophyll production
If an African violet has chlorosis, which of the following elements might be a useful addition to the soil?
e. magnesium
Iron deficiency is often indicated by chlorosis in newly formed leaves. This suggests that
a. iron is an immobile nutrient in plants.
There are several properties of a soil in which typical plants would grow well. Of the following, which would be the least conducive to plant growth?
c. high clay content
A soil well suited for the growth of most plants would have all of the following properties except
e. a high pH.