BY 124 Worksheet 6 : Chapter 37

  1. Soil can easily become deficient in ______because these ions are negatively charged and do not stick to negatively charged soil particles.

  1. ammonium

  1. nitrate

  1. potassium

  1. calcium

  1. magnesium

  1. The particles in soil are important because they ______.

  1. supply humus needed by plants

  1. fill spaces and keep oxygen out of the soil

  1. eliminate spaces for air and facilitate drainage

  1. are composed of nitrogen needed by plants

  1. are charged and hold ions needed by plants

  1. Fertilizers are usually enriched in ______.

  1. molybdenum, copper, and magnesium

  1. calcium and boron

  1. iron, manganese, and zinc

  1. all essential nutrients

  1. nitrogen, phosphorus, and potassium

  1. Why do farmers need to be concerned with the pH level of soil?

  1. Plants may turn blue if the pH is too high.

  1. The pH level of soil affects anion exchange and influences the chemical form of minerals.

  1. The pH level of soil affects water levels.

  1. The pH level of soil affects cation exchange and influences the chemical form of minerals.

  1. None of the listed responses is correct.

  1. At low soil pH levels (5 or less), what can happen?

  1. Toxic aluminum ions become more available, stunting the plant's growth.

  1. Cation exchange will be enhanced, causing the plants to grow faster.

  1. Plant roots are eaten away by the acidic soil.

  1. Absorption of negatively charged ions is enhanced, causing the plants to grow faster.

  1. Absorption of calcium is enhanced, but iron is unavailable.

  1. The biological process that produces 96% of the dry mass of a plant is called ______.

  1. cation exchange

  1. transpiration

  1. photosynthesis

  1. respiration

  1. oxidation

  1. Which of the following substances does a plant obtain from the air?

  1. water

  1. nitrogen

  1. carbon

  1. magnesium

  1. All of the listed responses are correct.

  1. A botanist claims to have discovered a new macronutrient required for plant growth. Most of this scientist's colleagues are skeptical of her claim. Why might they consider it unlikely?

  1. Plants manufacture their own macronutrients.

  1. Plants need thousands of nutrients; a new one is not significant.

  1. It is very difficult to prove that a plant needs a certain nutrient.

  1. All the nutrients required for plant growth have already been found.

  1. Any nutrient needed in large amounts (macronutrient) has probably been noted already.

  1. If a plant's leaves are yellowing, it may be that the plant is deficient in the elements needed to make chlorophyll, one of which is ______.

  1. magnesium

  1. molybdenum

  1. sulfur

  1. copper

  1. phosphorus

  1. If a plant is deficient in ______, it will NOT be able to make DNA.

  1. magnesium

  1. molybdenum

  1. sulfur

  1. copper

  1. phosphorus

  1. Soil could be deficient in any of the following nutrients. If you had to supply one of them, which would be needed in the smallest amount?

  1. iron

  1. nitrogen

  1. potassium

  1. phosphorus

  1. sulfur

  1. Which of the following is a true statement regarding mineral deficiency symptoms in plants?

  1. Deficiency symptoms of immobile nutrients will show up first in older organs.

  1. Symptoms always show up in younger leaves first.

  1. Deficiency symptoms of freely moving nutrients will show up first in younger organs.

  1. Growing tissues would show signs of mineral deficiency of mobile nutrients after older tissues.

  1. Symptoms of mineral deficiency always show up in older leaves first.

  1. When you add "plant food" to your potted geraniums, what are you actually providing the plant with?

  1. vitamins and amino acids

  1. minerals

  1. All of the listed responses are correct.

  1. complex carbohydrates

  1. sugars

  1. How did the addition of a gene for citrate synthesis increase the tolerance of tobacco and papaya plants to high aluminum concentrations in the soil?

  1. The citric acid produced by the plant coated the root tips and blocked the entrance of aluminum.

  1. The citric acid produced by the plants bound the free aluminum in the soil, making it less available to be taken up by the plants.

  1. The citric acid produced by the plant degraded the aluminum so that the plants couldn't take it up.

  1. The citric acid produced by the plant dissolved the aluminum in the soil.

  1. All of the listed responses are correct.

  1. What supplies the energy for most of the microorganisms in the rhizosphere?

  1. plants

  1. soil bacteria

  1. mycorrhizae

  1. nitrogen-fixing bacteria

  1. earthworms

  1. The most abundant gas in our atmosphere cannot be used by plants directly in its atmospheric form. Fortunately, this gas is made available to some plants by certain bacteria that live symbiotically in their roots. What is this gas?

  1. hydrogen

  1. iron

  1. carbon dioxide

  1. nitrogen

  1. oxygen

  1. Nitrogen fixation is ______.

  1. the recycling of nitrogen from organic matter in the soil

  1. the use of nitrogen to build molecules such as proteins and nucleic acids

  1. performed by fungi inhabiting root nodules

  1. the absorption of N2 from the soil

  1. the conversion of nitrogen gas in the air to a form usable by plants

  1. The enzyme complex that catalyzes the conversion of atmospheric nitrogen to ammonia is ______.

  1. rhizobium

  1. leghemoglobin

  1. rubisco

  1. hydrogenase

  1. nitrogenase

  1. Which of the following organisms can fix nitrogen?

  1. legumes

  1. Rhizobia

  1. Azolla

  1. lichens

  1. mycorrhizal fungi

  1. Legumes (members of the pea family) have roots with swellings called nodules that ______.

  1. increase the surface area for water uptake

  1. contain nitrogen-fixing bacteria

  1. produce antibiotics that protect the plant from soil bacteria

  1. form fungal hyphae

  1. provide a steady supply of sugar to the host plant

  1. Which of these describes the initial interaction between Rhizobium and a soybean root?

  1. The nodule develops vascular tissue.

  1. Vesicles containing bacteria bud into cortical cells.

  1. There is nodule growth in response to secretions from Rhizobium.

  1. An infection thread is initiated in the root hair of the legume.

  1. Soybeans secrete chemical signals that are detected by Rhizobium.

  1. In root nodules, the plants provide ______, and the bacteria provide ______.

  1. carbohydrates ... fixed nitrogen

  1. amino acids ... ATP

  1. ATP ... nitrogen gas

  1. carbohydrates ... nitrogen gas

  1. an aerobic environment ... fixed nitrogen

  1. Mycorrhizae develop ______.

  1. to control the evaporation of water from leaves

  1. only in plants such as mistletoe that parasitize other plants

  1. when soil is too compact and lacks sufficient air spaces

  1. between roots and beneficial fungi

  1. as stored nutrients to support the plant when necessary

  1. Which of the following is true of mycorrhizae?

  1. Arbuscular mycorrhizae do not have a dense mantle ensheathing roots.

  1. Arbuscular mycorrhizae penetrate the cytoplasm of root cells.

  1. The fungal hyphae of ectomycorrhizae form arbuscules.

  1. Ectomycorrhizae are found in many crop plants, such as wheat and maize.

  1. None of the listed responses is correct.

  1. By trapping insects, carnivorous plants obtain ______, which they need ______.

  1. phosphorus ... to make protein

  1. sugars ... because they can't make enough in photosynthesis

  1. nitrogen ... to make sugar

  1. nitrogen ... to make protein

  1. water ... because they live in dry soil

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