Resource Acquisition, Nutrition, and Transport in Vascular Plants 29 Resource Acquisition, Nutrition, and Transport in Vascular Plants Questions prepared by Loraine Washburn, Bowdoin College

In plants’ transition to land, critical adaptations for survival that arose included all except photosynthesis. the cuticle. stomata. bulk flow. rhizoids. Answer: A

In plants’ transition to land, critical adaptations for survival that arose included all except photosynthesis. the cuticle. stomata. bulk flow. rhizoids. 3

Which statement about the movement of water and nutrients in plants is true? Water and nutrients move from the roots to the leaves via the stem or trunk. Water and nutrients move from the leaves to the roots via the stem or trunk. Water and nutrients can move either from leaves to roots or from roots to leaves via the stem or trunk. Water and nutrients are taken up by the roots and move by active transport to the leaves. Water and nutrients are pumped from the roots to the leaves via a proton pump. Answer: C 4

Which statement about the movement of water and nutrients in plants is true? Water and nutrients move from the roots to the leaves via the stem or trunk. Water and nutrients move from the leaves to the roots via the stem or trunk. Water and nutrients can move either from leaves to roots or from roots to leaves via the stem or trunk. Water and nutrients are taken up by the roots and move by active transport to the leaves. Water and nutrients are pumped from the roots to the leaves via a proton pump. 5

The difference between macronutrients and micronutrients is that the molecules of macronutrients are larger than those of micronutrients. macronutrients are essential for physiological function of plants, while micronutrients amplify plant growth if they are available. macronutrients are needed for growth, while micronutrients are needed only for reproduction. macronutrients are required by plants in larger quantities than are micronutrients. the molecules of macronutrients move through the symplast, and micronutrients can move through either the symplast or the apoplast. Answer: D 6

The difference between macronutrients and micronutrients is that the molecules of macronutrients are larger than those of micronutrients. macronutrients are essential for physiological function of plants, while micronutrients amplify plant growth if they are available. macronutrients are needed for growth, while micronutrients are needed only for reproduction. macronutrients are required by plants in larger quantities than are micronutrients. the molecules of macronutrients move through the symplast, and micronutrients can move through either the symplast or the apoplast. 7

nitrifying bacteria, which oxidize ammonium to nitrite. Legumes (such as soybeans) commonly obtain their nitrogen through a mutualistic association with nitrifying bacteria, which oxidize ammonium to nitrite. ammonifying bacteria, which convert organic nitrogen to ammonium. denitrifying bacteria, which convert organic nitrite to ammonium. nitrifying bacteria, which extract nitrogen from decomposing animals. nitrogen-fixing bacteria, which convert gaseous nitrogen to ammonium. Answer: E 8

nitrifying bacteria, which oxidize ammonium to nitrite. Legumes (such as soybeans) commonly obtain their nitrogen through a mutualistic association with nitrifying bacteria, which oxidize ammonium to nitrite. ammonifying bacteria, which convert organic nitrogen to ammonium. denitrifying bacteria, which convert organic nitrite to ammonium. nitrifying bacteria, which extract nitrogen from decomposing animals. nitrogen-fixing bacteria, which convert gaseous nitrogen to ammonium. 9

About ____% of a plant’s water escapes through the stomata, although the stomata account for just ____% of the external leaf surface. 75; 10 75; 1–2 95; 10 95; 1–2 Answer: D 10

About ____% of a plant’s water escapes through the stomata, although the stomata account for just ____% of the external leaf surface. 75; 10 75; 1–2 95; 10 95; 1–2 11

Which statement most accurately reflects the interaction between plants and the soil in the rhizosphere in which they grow? Plants passively take up nitrogen from the soil with their roots, interacting little with the rhizosphere. Plants obtain nitrogen through a two-way interaction assisted by metabolism of rhizosphere bacteria to render nitrogen to useable forms, while plants lose carbon to the bacteria. Plants’ ability to absorb nitrogen is compromised due to high concentrations of bacteria in the rhizosphere. Rhizosphere bacteria form chains of cells that penetrate the plant root and facilitate plant nitrogen absorption through capillary action. Answer: B 12

Which statement most accurately reflects the interaction between plants and the soil in the rhizosphere in which they grow? Plants passively take up nitrogen from the soil with their roots, interacting little with the rhizosphere. Plants obtain nitrogen through a two-way interaction assisted by metabolism of rhizosphere bacteria to render nitrogen to useable forms, while plants lose carbon to the bacteria. Plants’ ability to absorb nitrogen is compromised due to high concentrations of bacteria in the rhizosphere. Rhizosphere bacteria form chains of cells that penetrate the plant root and facilitate plant nitrogen absorption through capillary action. 13

The basis of transpirational pull in the xylem is positive root pressure from differences in solute potential between soil and root. hydrostatic pressure generated by the shrinking in diameter of the trunk or stem. negative pressure at the air-water interface in the leaf. pressure created by proton pumping of stomatal guard cells. adhesion tension of water molecules to xylem cell walls. Answer: C 14

The basis of transpirational pull in the xylem is positive root pressure from differences in solute potential between soil and root. hydrostatic pressure generated by the shrinking in diameter of the trunk or stem. negative pressure at the air-water interface in the leaf. pressure created by proton pumping of stomatal guard cells. adhesion tension of water molecules to xylem cell walls. 15

outside air   leaf mesophyll   root  leaf   trunk   soil  Which inequality reflects the correct relationship of water potentials during active daytime photosynthesis in a typical tree? leaf   trunk   soil  outside air   leaf mesophyll   root  leaf   trunk   soil  soil   root   leaf  Answer: A 16

outside air   leaf mesophyll   root  leaf   trunk   soil  Which inequality reflects the correct relationship of water potentials during active daytime photosynthesis in a typical tree? leaf   trunk   soil  outside air   leaf mesophyll   root  leaf   trunk   soil  soil   root   leaf  17

Changing nitrogen inputs can cause loss of biodiversity. In a changing world, where humans have more than doubled the annual production of nitrogen through fertilizer manufacture and extensive planting of legumes, all of the following are true except which one? This is a boon to agriculture, while natural ecosystems can grow more lushly. There are concomitant changes in the soil, in the abundances of nitrifying and denitrifying bacterial communities. Excess nitrogen is leading to overabundance of algal growth in aquatic systems, lowering water quality. This is bringing about a decrease in the abundance of mycorrhizal fungi in the soil, with potential negative consequences for agriculture. Changing nitrogen inputs can cause loss of biodiversity. Answer: A 18

Changing nitrogen inputs can cause loss of biodiversity. In a changing world, where humans have more than doubled the annual production of nitrogen through fertilizer manufacture and extensive planting of legumes, all of the following are true except which one? This is a boon to agriculture, while natural ecosystems can grow more lushly. There are concomitant changes in the soil, in the abundances of nitrifying and denitrifying bacterial communities. Excess nitrogen is leading to overabundance of algal growth in aquatic systems, lowering water quality. This is bringing about a decrease in the abundance of mycorrhizal fungi in the soil, with potential negative consequences for agriculture. Changing nitrogen inputs can cause loss of biodiversity. 19

Water can enter roots through two pathways, apoplastic and symplastic routes. How do these pathways differ? The apoplastic route is for water and the symplastic route is for nutrients. The apoplastic route does not involve transport across a cell membrane, but the symplastic route does. The apoplastic route is for nutrients and the symplastic route is for water. The apoplastic route is used in xylem and the symplastic route in phloem. Answer: B 20

Water can enter roots through two pathways, apoplastic and symplastic routes. How do these pathways differ? The apoplastic route is for water and the symplastic route is for nutrients. The apoplastic route does not involve transport across a cell membrane, but the symplastic route does. The apoplastic route is for nutrients and the symplastic route is for water. The apoplastic route is used in xylem and the symplastic route in phloem. 21