Chapter 26

In land plants what % of the water transported by the xylem is used for metabolism? a. 32% b. 66% c. 85% d. 90% e. 2%

2%

____restrict the amount of water vapor that diffuses out of the plant's surfaces - but also restrict access to CO2 for photosynthesis, and oxygen for aerobic respiration

A cuticle and stomata

What benefit do root hairs provide to the plant? a. Increased nutrient absorbing ability b. Increase in surface area of the root system c. All of these choices. d. None of these choices. e. Increased water absorbing ability

All of these choices.

What features are typical of plants that are good at performing phytoremediation? a. All of these choices. b. None of these choices. c. Grow rapidly d. Grow large e. Able to uptake large amounts of contaminants

All of these choices.

Carbon, hydrogen and oxygen are _____ for plants a. macronutrients b. micronutrients c. trace elements d. required elements e. both a and d

Both a and d

Which of the following is a macronutrient? a. Calcium b. Boron c. Zinc d. Iron e. Copper

Calcium

Waxy, waterproof band that seals abutting cell walls of root endodermal cells Soil water can only enter the vascular cylinder by passing through an endodermal cell, which is covered by a waterproof _____ Transport proteins in the cells' plasma membranes control the movement of mineral ions from soil water into the plant body

Casparian strip

Steps in Pressure Flow Theory

Companion cells load sugars into sieve-tube members by active transport Solute concentration in sieve tubes increases, so water moves in by osmosis - increased fluid volume increases internal pressure (turgor) High pressure pushes fluid toward sink regions Pressure and solute concentrations decrease as fluid moves from source to sink Sugars are unloaded at sink regions; water follows by osmosis

Which two properties of water are the main driving factors behind the movement of water in vascular plants? a. Evaporation and cohesion b. Passive transport and cohesion c. Active transport and cohesion d. Diffusion and osmosis e. Cohesion and facilitate diffusion

Evaporation and cohesion

____ drives the upward movement of water through xylem inside a vascular plant

Evaporation from leaves and stems - Transpiration

One of a pair of cells that define a stoma across the epidermis of a leaf or stem

Guard cell

Decaying organic matter in soil; provides nutrients; negatively charged organic acids trap positive mineral ions

Humus

Which type of bond holds the water droplets together as they are being pulled up the plant's vascular system? a. Ionic b. Polar covalent c. Hydrogen d. Covalent e. Double covalent

Hydrogen

Process by which water moving through soil removes nutrients from it ___carries away soil nutrients; it is fastest in sandy soils, which do not bind nutrients as well as clay soils

Leaching

The role of companion cells in translocation is to A. Assist vessel members in transport of organics. B. Supply needed potassium ions for water transport. C. Load organic compounds into nearby sieve tubes. D. Supply both energy and potassium to sieve tube members. E. Supply both energy and potassium to sieve tube members and assist vessel members in transport of organics.

Load organic compounds into nearby sieve tubes.

Soil with roughly equal amounts of sand, silt, and clay have the best oxygen and water penetration

Loams

Which plant specialization mutually benefits the young root and a fungus? a. Mycorrhizae b. Root nodules c. None of these choices. d. All of these choices. e. Root hairs

Mycorrhizae

Plant growth requires the sixteen elements:

Nine elements are macronutrients, required in amounts above 0.5% of the plant's dry weight Seven other elements are micronutrients, which make up traces of the plant body Carbon, oxygen, and hydrogen are obtained from air and water Other nutrients are taken up by roots as minerals dissolved in soil water

Conversion of nitrogen gas to ammonia

Nitrogen Fixation Nitrogen-fixing bacteria form root nodules on clover, peas, and other legumes In nitrogen fixation, a bacterial enzyme uses ATP to convert nitrogen gas to ammonia (NH3) Other bacteria convert ammonia to nitrate (NO3-), a form of nitrogen that plants can absorb

Which macronutrient is responsible for the activation of enzymes in plants? a. Copper b. Zinc c. Potassium d. Sulfur e. Carbon

Potassium

thin extensions of root epidermal cells - enormously increase surface area absorbing water and nutrients They do not develop into new roots, and last only a few days

Root hairs

consists of particles from weathered rocks, mixed with variable amounts of decomposing organic material (humus) Mineral particles (sand, silt, and clay) differ in size and chemical properties Sand and silt provide air spaces Negatively-charged clay attracts positive mineral ions

Soil Mixture of various mineral particles and humus

________ is the loss of soil under the force of wind and water. a. Decomposition b. Soil erosion c. Bioremediation d. Leaching e. Phytoremediation

Soil erosion

What is the main form of stored carbohydrates in plants? a. Glucose b. Cellulose c. Chitin d. Glycogen e. Starch

Starch

Through which plant structure does the majority of water evaporate? a. Leaves b. Root hairs c. Stoma d. Root nodules e. Stroma

Stoma

Which two structures will help the plant conserve water during times of drought? a. Stomata and porous roots b. Cuticle and broad surface area on the leaves c. Stomata and cuticle d. Stomata and porous epidermis e. Cuticle and porous roots

Stomata and cuticle

In CAM plants, A. Stomata remain open day and night. B. The stomata are open during the day. C. There are no stomata, which decreases water loss. D. Stomata open at night. E. Guard cells are reversed, closing when turgid and opening when flaccid.

Stomata open at night

___prevents water loss from evaporation It consists of epidermal cell secretions: waxes, pectin, and cellulose fibers embedded in cutin, an insoluble lipid polymer ____ is translucent, so it does not prevent light from reaching photosynthetic tissues

The cuticle

When compared to the conducting tubes of xylem what is unique about phloem? a. The sieve tubes are folded over. b. The sieve tubes are formed from vessel elements. c. The sieve tubes contain tracheids. d. The sieve tubes are blocked. e. The sieve tubes are living.

The sieve tubes are living.

Uppermost soil layer Contains the most nutrients for plant growth _____typically contains the greatest amount of organic matter, so the roots of most plants grow most densely in it

Topsoil

Process that moves organic molecules through phloem Organic compounds in phloem flow from a source - region where companion cells load molecules into sieve tubes - to a sink - region where molecules are being used or stored

Translocation

Factors Affecting Stomata

Water availability, the level of carbon dioxide inside the leaf, and light intensity affect whether stomata open or close Examples: Light causes guard cells to pump potassium ions into their cytoplasm; the stoma opens to begin photosynthesis Root cells release abscisic acid (ABA) when soil water becomes scarce; binding in guard cells closes stoma

___ allows it to be pulled from roots into all other parts of the plant

Water's cohesion

Transport of photosynthetically produced sugars from leaves to roots occurs by___ a. pressure flow b. differences in source and sink solute concentrations c. the pumping force of xylem vessels d. transpiration, tension, and cohesion of water e. a and b

a and b: pressure flow and differences in source and sink solute

When guard cells swell, ____ a. transpiration ceases b. sugars enter phloem c. a stoma open d. root cells die

a stoma open

when soil is dry, guard cells respond to ___ by collapsing against on another, so stomata close a. air temperature b. low humidity c. abscisic acid d. oxygen

abscisic acid

The sink region in the pressure flow explanation of phloem transport could be A. growing leaves B. seeds C. fruits D. roots E. all of these

all of these

The stomata A. only open at night B. are open when guard cells are turgid C. close when the turgor pressure of guard cells increases D. are covered by the cuticle to reduce water loss E. all of these

are open when guard cells are turgid

A vascular cylinder consists of cells of the ____ a. exodermis b. endodermis c. root cortex d. xylem and phloem e. b and d f. all of the above

b and d: endodermis, xylem and phloem

The movement of materials already in the phloem is described using the term(s) A. source-to-sink B. pressure flow C. cohesion D. active transport E. both source-to-sink and pressure flow

both source-to-sink and pressure flow

A _____ strip between abutting endodermal cell walls forces water and solutes to move through these cells rather than around them a. cutin b. casparian c. cohesion d. cellulose

casparian

The inorganic soil constituent with the finest particles is A. clay B. gravel C. humus D. sand E. silt

clay

At night, the stomata of most plants will ________. a. close b. open c. close to prevent the loss of oxygen from the leaf d. regulate the diffusion of nitrogen e. regulate the diffusion of carbon dioxide

close

Which part of the theory of water transport states that hydrogen bonding allows water molecules to maintain a continuous fluid column as water is pulled from roots to leaves? A. pressure flow B. evaporation C. cohesion D. abscission E. fusion

cohesion

How transpiration creates a tension that pulls a cohesive column of water through xylem, from roots to shoots

cohesion-tension theory

The waxy covering of the leaf is the A. cuticle B. epidermis C. Casparian strip D. stomata E. none of these

cuticle

The Casparian strip is associated with the A. epidermis B. vascular tissue C. cortex D. root hairs E. endodermis

endodermis

A waxy cuticle is secreted by _____ a. ground tissue b. epidermal cells c. a stoma d. root hairs

epidermal cells

Mycorrhizae are A. roots B. bacteria-root associations C. fungus-root associations D. bacteria E. small animals found in agricultural soils

fungus-root associations

The cells that surround stomata are A. endodermal cells B. guard cells C. mesophyll cells D. vascular bundle cells E. vessel cells

guard cells

Stomata open in response to light when____ a. guard cells pumps ion into their cytoplasm b. guard cells pump ions out of their cytoplasm c. water evaporates out of guard cells

guard cells pumps ion into their cytoplasm

Decomposing matter in soil is called_____ a. loam b. humus c. topsoil d. nutrients

humus

What is the organic constituent of soil called? A. clay B. gravel C. humus D. sand E. silt

humus

Most of the water that enters the plant A. leaves the plant through the root system B. is lost through transpiration C. remains in the plant to form the high concentration of water in plant tissue D. remains in the plant to function in translocation E. is used up in cellular metabolism

is lost through transpiration

The soil type that has the best oxygen concentration and water penetration is called ________. a. rock b. topsoil c. leaching d. loam e. humus

loam

The type of relationship between nitrogen fixing bacteria and the roots of various plants is ________. a. parasitic b. None of these c. mutually beneficial d. predatory e. commensalistic

mutually beneficial

Fungal hyphae in and around roots help roots absorb mineral ions from a larger volume of soil than roots alone Mutually beneficial fungus-plant root partnership

mycorrhiza

The nutrition of some plants depends on a mutually beneficial association between a root and a fungus. The association is known as a____ a. root nodule b. mycorrhiza c. root hair d. root hypha

mycorrhiza

According to the pressure flow theory what do sugars do in the sieve tube members? a. Decrease the solute concentration and cause water to move into the tube. b. Increase the solute concentration and cause water to move into the tube. c. Increase the solute concentration and cause water to move out of the tube. d. Sugars are not associated with the pressure flow theory. e. Decrease the solute concentration and cause water to move out of the tube.

ncrease the solute concentration and cause water to move into the tube.

Water inside all of the xylem cells is being pulled upward by A. turgor pressure B. negative pressures (tensions) C. osmotic gradients D. pressure flow forces E. all of these

negative pressures (tensions)

Nodules found on the roots of leguminous plants are involved in supplying which element for the plant? A. aluminum B. boron C. magnesium D. nitrogen E. chlorine

nitrogen

Which of the following would not be used when describing a Casparian strip? A. waxy B. endodermis C. permeable D. exodermis E. waterproof

permeable

Sieve tubes are part of ____ a. cortex b. mesophyll c. phloem d. xylem

phloem

Sugars are usually carried throughout the plant in which tissue? A. cortex B. parenchyma C. xylem D. phloem E. cambium

phloem

The process by which plants take up and concentrate or degrade environmental contaminants is called ________. a. cellular respiration b. bioaugmentation c. phytoremediation d. bioremediation e. photosynthesis

phytoremediation

Explanation of how flow of fluid through phloem is driven by differences in pressure and sugar concentration between a source and a sink

pressure flow theory

Anaerobic bacteria in root nodules share their fixed nitrogen with certain plants Swellings of some plant roots that contain nitrogen-fixing bacteria

root nodules

Loss of soil under the force of wind and water Nutrients are also lost through ____; strong winds, fast-moving water, sparse vegetation, and poor farming practices cause the greatest losses

soil erosion

The openings in leaves that function to exchange gases are called A. cuticles B. stomata C. guard cells D. pits E. pores

stomata

Two specialized cells (guard cells) define each ___ When guard cells swell with water, a gap forms between them When guard cells lose water, the gap closes

stomata

The most common form of sugar transported to the roots is A. glucose B. fructose C. sucrose D. ribose E. starch

sucrose

Movement of soluble organic material through plants is known as A. translocation B. active transport C. passive transport D. transpiration E. none of these

translocation

Water evaporation from plant parts is called____ a. translocation b. expiration c. transpiration d. tension

transpiration

Water transport from roots to leaves occurs mainly because of_____ a. pressure flow b. differences in source and sink solute concentrations c. the pumping force of xylem vessels d. transpiration, tension, and cohesion of water e. a and b

transpiration, tension, and cohesion of water

Even though plant cell walls in the root system are rigid they are permeable to ________. a. water and ions b. sunlight and oxygen c. sunlight and potassium d. water and sunlight e. They are not permeable to anything.

water and ions

Tracheids are part of ____ a. cortex b. mesophyll c. phloem d. xylem

xylem

The cohesion-tension theory indicates that the water located in the ________ is under a constant state of ________ pressure. a. phloem, negative b. xylem, positive c. xylem, negative d. phloem, positive e. xylem, partial

xylem, negative