1. Explain how the phrase “too much of a good thing” can apply to watering and fertilizing plants.

Overwatering deprives roots of oxygen. Overfertilizing is wasteful and can lead to soil salinization and water pollution

2. Some lawn mowers collect clippings for easy disposal and to prevent clumps from inhibiting photosynthesis. What is a possible drawback of this practice with respect to plant nutrition?

As lawn clippings decompose, they restore mineral nutrients to the soil. If they are removed, the minerals lost from the soil must be replaced by fertilization.

3. How would adding clay to loamy soil affect the soil’s capacity to exchange cations and retain water? Explain.

Because of their small size and negative charge, clay particles would increase the number of binding sites for cations and water molecules and would therefore increase cation exchange and water retention in the soil.

4. Explain how the forms of nutrients available to plants explains Stephen Hales’s hypothesis that air is a substance with mass and that plants are nourished mostly by air.

Table 37.1 shows that CO2 is the source of 90% of a plant’s dry weight, supporting Hale’s view that plants are nourished mostly by air.

5. Are some essential elements more important than others? Explain.

No, because even though macronutrients are required in greater amounts, all essential elements are necessary for the plant to complete its life cycle.

6. The element silicon (Si) is absorbed by plants and increases the quality and yield of agricultural crops. Would this be sufficient evidence to consider it an essential plant nutrient?

No. Most plants can complete their life cycles in the absence of silicon. Therefore, by definition, it is not an essential nutrient.

7. Why is the study of the rhizosphere critical to understanding plant nutrition?

The rhizosphere is a narrow zone in the soil immediately adjacent to living roots. This zone is especially rich in both organic and inorganic nutrients and has a microbial population that is many times greater than the bulk of the soil.

8. How do soil bacteria and mycorrhizae contribute to plant nutrition?

Soil bacteria and mycorrhizae enhance plant nutrition by making certain minerals more available for plants.

9. A peanut farmer finds that the older leaves of his plant are turning yellow following a long period of wet weather. Suggest a reason why.

The constant rainfall depletes the soil of oxygen. heavy rain may leach nitrate from the soil. A symptom of nitrogen deficiency is yellowing of older leaves.

Help

Options

focusNode

Didn't know it?
click below

Knew it?
click below

Don't Know

Remaining cards (0)

Know

retry

shuffle

restart

0:00

Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

Normal Size Small Size show me how

Ch 37 for Bio

Soil and Plant Nutrition

Question	Answer
1. Explain how the phrase “too much of a good thing” can apply to watering and fertilizing plants.	Overwatering deprives roots of oxygen. Overfertilizing is wasteful and can lead to soil salinization and water pollution
2. Some lawn mowers collect clippings for easy disposal and to prevent clumps from inhibiting photosynthesis. What is a possible drawback of this practice with respect to plant nutrition?	As lawn clippings decompose, they restore mineral nutrients to the soil. If they are removed, the minerals lost from the soil must be replaced by fertilization.
3. How would adding clay to loamy soil affect the soil’s capacity to exchange cations and retain water? Explain.	Because of their small size and negative charge, clay particles would increase the number of binding sites for cations and water molecules and would therefore increase cation exchange and water retention in the soil.
4. Explain how the forms of nutrients available to plants explains Stephen Hales’s hypothesis that air is a substance with mass and that plants are nourished mostly by air.	Table 37.1 shows that CO2 is the source of 90% of a plant’s dry weight, supporting Hale’s view that plants are nourished mostly by air.
5. Are some essential elements more important than others? Explain.	No, because even though macronutrients are required in greater amounts, all essential elements are necessary for the plant to complete its life cycle.
6. The element silicon (Si) is absorbed by plants and increases the quality and yield of agricultural crops. Would this be sufficient evidence to consider it an essential plant nutrient?	No. Most plants can complete their life cycles in the absence of silicon. Therefore, by definition, it is not an essential nutrient.
7. Why is the study of the rhizosphere critical to understanding plant nutrition?	The rhizosphere is a narrow zone in the soil immediately adjacent to living roots. This zone is especially rich in both organic and inorganic nutrients and has a microbial population that is many times greater than the bulk of the soil.
8. How do soil bacteria and mycorrhizae contribute to plant nutrition?	Soil bacteria and mycorrhizae enhance plant nutrition by making certain minerals more available for plants.
9. A peanut farmer finds that the older leaves of his plant are turning yellow following a long period of wet weather. Suggest a reason why.	The constant rainfall depletes the soil of oxygen. heavy rain may leach nitrate from the soil. A symptom of nitrogen deficiency is yellowing of older leaves.

Created by: titiwalton

Popular Biology sets

Genetics: Monohybrid, Dihybrid, & Non-Mendelian

Unit 2- Requirements of Life

Evidence of Evolution

"Know" box contains:
Time elapsed:
Retries: