Bio Chapter 37

If a wide-spectrum fungicide that kills all fungal species were used extensively in a forest, what effects would you expect the treatment to have on the forest vegetation? a) It would greatly reduce the ability of most plants to take up water and minerals from soil. b) It would benefit plants by killing off fungal pathogens. c) It would harm the few plants that benefit from mutualistic relationships with mycorrhizal fungi.

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 for this difference is that a) the humus made the soil more loosely packed, so water penetrated more easily to the roots. b) the humus contained minerals such as magnesium and iron, needed for the synthesis of chlorophyll. c) the healthy plants absorbed chlorophyll from the humus. d) the healthy plants used the food in the decomposing leaves of the humus for energy to make chlorophyll. e) the heat released by the decomposing leaves of the humus caused more rapid growth and chlorophyll synthesis.

We would expect the greatest difference in plant health between two groups of plants of the same species, one group with mycorrhizae and one group without mycorrhizae, in an environment a) where nitrogen-fixing bacteria are abundant. b) that has hot summers and cold winters. c) in which the soil is relatively deficient in mineral nutrients. d) that has soil with poor drainage. e) that is near a body of water, such as a pond or river.

A mineral deficiency is likely to affect older leaves more than younger leaves if a) the mineral is a macronutrient. b) the mineral is a micronutrient. c) the older leaves are in direct sunlight. d) the mineral is required for chlorophyll synthesis. e) the mineral is very mobile within the plant.

Micronutrients are needed in very small amounts because a) only the most actively growing regions of the plants require micronutrients. b) most serve mainly as cofactors of enzymes. c) they play only a minor role in the growth and health of the plant. d) most of them are mobile in the plant. e) most are supplied in large enough quantities in seeds.

Most of the mass of organic material of a plant comes from a) nitrogen. b) soil minerals. c) atmospheric oxygen. d) carbon dioxide. e) water.

On average, how far do agricultural products travel from farm to plate in the United States? a) 100 miles b) 400 miles c) 800 miles d) 1100 miles e) 1400 miles

Today, it takes about ______ Calories of energy to produce about 1 Calorie of food. a) 2 b) 20 c) 55 d) 90 e) 125

When does Cognito Farm use antibiotics on its cattle? a) Monthly to prevent illness. b) Weekly to prevent illness. c) Daily to prevent illness. d) Only when they are sick. e) Never

It has been estimated that confined animal feeding operations contribute to about _____ of world carbon dioxide emissions. a) 5% b) 15% c) 25% d) 35% e) 45%

What is used at Cognito Farm to control fly larvae in the pasture? a) insect traps b) chickens c) chemical pesticides d) all natural organic pesticides e) ultraviolet radiation

Cognito Farm avoids washing chicken carcasses with __________, which is done at many packing plants in the United States. a) bleach b) salt water c) hydrochloric acid d) calcium carbonate e) acetic acid

What are the largest particles formed from the breakdown of rock? a) Clay b) Silt c) Gravel d) Sand

Which of the following is an elemental ion? a) K+ b) HCO−3 c) K d) NO−3

True or false? Soil texture affects the amount of water available to plants; water is held best by clay and sand particles. a) True b) False

Which of the following steps occurs first during soil formation? a) Lichens grow on the rock surface. b) Organic material is added to the rock surface. c) Weathering of solid rock occurs. d) Mosses grow on the rock surface.

Why is the decomposition of dead organisms important for soil formation? a) The process makes negatively charged ions more easily absorbed by plant roots. b) The process adds organic matter to the soil, which is necessary to support the growth of larger plants. c) The process produces acidic compounds that dissolve the rock surface. d) The process increases the amount of silt in the soil.

Which of the following statements about nutrient uptake by plants is true? a) Root hairs increase the volume of roots for more efficient absorption of water and nutrients. b) Plants can easily absorb mineral ions from soil with large amounts of organic matter. c) Plants require other elements besides carbon, hydrogen, and oxygen to grow, and they can obtain these in soil. d) Positively charged ions remain dissolved in water and are easily absorbed by plant roots.

True or false? Plants use both active and passive transport processes to transport ions against their concentration gradients. a) True b) False

The release of CO2 into the soil results in the formation of _____. a) hydrogen ions and oxygen ions b) sodium ions and chloride ions c) hydrogen ions and carbonate ions d) potassium ions and calcium ions e) carbonate ions and oxygen ions

What process is the source of the CO2 that root hairs release into the soil? a) respiration and photolysis b) respiration c) photosynthesis d) photosynthesis and respiration e) photolysis

The binding of H+ ions to soil particles _____. a) promotes the clumping of soil particles b) is counteracted by acid precipitation c) displaces nitrates from soil particles d) displaces mineral cations e) displaces mineral anions

Which of these ions is most likely to be leached from the soil? a) potassium ions b) calcium ions c) magnesium ions d) iron ions e) chlorine ions

Acid precipitation _____. a) promotes the attachment of anions to soil particles b) has no effect on soil fertility c) enhances the diffusion of cations into root hairs d) decreases soil fertility e) increases soil fertility

How do cations enter root hairs? a) endocytosis b) diffusion c) active transport d) osmosis e) phagocytosis