Plant Science Final Exam Review

Define phellogen.

(Cork cambium) Meristematic tissue that provides cells that grow both outward and inward

Define spongy mesophyll parenchyma cells.

- Cell layer in a leaf located between the palisade parenchyma and the lower epidermis - These cells have thin cell walls and are loosely packed

Define palisade parenchyma cells.

- Cell layer in leaves immediately below the upper epidermis - Packed with chloroplasts - Found in dicots, but not in monocots

Define cotyledon.

- Leaf-like structures at the first node of the seedling stem - Often referred to as seed leaves - In some dicots, cotyledons contain stored food for the young plant not able to photosynthesize its own food yet

Define integuments.

- Tissues covering or surrounding the ovule, usually consisting of an inner and outer layer - Subsequently become the seedcoats of the mature ovule

Define glacial till.

-Product of glacial weathering, best agricultural soil

Average lot sized for new homes are about _____________________________.

0.15 hectare, or 0.40 acre

It is possible to feed an adult on a plant diet from about _____________ of land.

0.2 hectares

List the categories in which symptoms can generally be placed.

1) Abnormal tissue coloration 2) Wilting 3) Tissue death 4) Defoliation 5) Abnormal increase in tissue size 6) Dwarfing 7) Replacement of host plant tissue by tissue of the infectious organism

Some important commercial uses of synthetic auxins are ___________________.

1) Adventitious root initiation 2) Weed control 3) Inhibition of stem sprouting 4) Tissue culture

The four principal function of roots in higher plants are: _____________________

1) Anchoring plants in the soil 2) Absorbing water and mineral nutrients 3) Conducting water and dissolved minerals, as well as organic materials, to other parts of the plant 4) Storing food materials Ex: In plants such as sweet potatoes, sugar beets, and carrots

There are five traditionally recognized groups of natural plant hormones: ______________________

1) Auxins 2) Gibberellins 3) Cytokinins 4) Ethylene 5) Abscisic acid

What are the six common functional groups for grasslands? Give examples of each.

1) C3 (cool season grasses)- perennial ryegrass, orchardgrass, timothy, Kentucky bluegrass, tall fescue, reed canary grass, crested wheatgrass, smooth bromegrass 2) Legumes- alfalfa, red clover, white clover, birdsfoot, trefoil, lespedeza 3) C4 (warm season grasses)- Bermuda grass, big bluestem, switchgrass, indiangrass, limpograss, paspalum 4) Forbs- chicory, plantain (buckthorn) 5) Annual species- cereal rye, wheat, oats, subteranean clover, annual bromegrass 6) Shrubs

Cultivated plants are grouped into 6 categories. List those 6 categories and examples of each.

1) Cereal crops- wheat, maize (corn), rice, barley, oats, sorghum, rye, and millet 2) Roots and tubers- potatoes, sweet potatoes, and cassavas 3) Oil crops- soybeans, corn, peanuts, palm, coconuts, sunflowers, olive, and safflower 4) Sugar- sugar cane and sugar beets 5) Fruit crops- bananas, oranges, apples, pears, etc. 6) Vegetable crops- tomatoes, lettuce, carrots, melons, asparagus, etc.

List the management practices for controlling insect pests and give examples of each where appropriate.

1) Cultural practices (timing of planting, tillage, crop rotation) 2) Seed, soil, and foliar applied insecticides 3) Biological control (reducing pest populations through use of natural predators) 4) Insect resistant crops (varietal/hybrid tolerance to insect pests

List the five step approach referred to on page 333 available for diagnosing plant disorders. Be familiar what takes place in each step.

1) Define the problem 2) Examine the entire plant community 3) Look for patterns 4) Consider how the damage developed over time 5) Ask questions, gather information, and determine the causes of the plant damage

What are the three basic parts of the seed?

1) Embryo 2) Food storage tissue (endosperm, cotyledons, or perisperm) 3) Seed coats

What are the phases of development that a seedling will undergo?

1) Embryonic growth 2) Juvenility 3) Transition stage- called "phase change" in plants 4) Maturity or adult phase 5) Senescence- deterioration with age/loss of a cells power of division and growth 6) Death

List and describe the three groups in which higher plant parasites can be placed.

1) Epiphytes- use host plant for physical support and protection (little or no harm to host plant) 2) Hemiparasites- absorb water and mineral nutrients from host plant (harm host plant) 3) True parasites- depend on host plant for all nourishment

Fruit and seed production involves seven phases: _______________________

1) Flower induction and initiation 2) Flower differentiation and development 3) Pollination 4) Fertilization 5) Fruit set and seed formation 6) Growth and maturation of fruit and seed 7) Fruit senescence

The main plant factors affecting forage fiber and other quality factors are: __________.

1) Forage species 2) Leaf-to-stem ratio 3) Maturity 4) Antiquality components

In contrast to some of the other plant hormones, ethylene and ethylene-releasing chemicals have several valuable commercial applications: ____________

1) Fruit ripening 2) Flower initiation 3) Changing sex expression 4) Degreening oranges, lemons, and grapefruit 5) Harvest aids 6) Growth regulation

List and define the five methods for managing plant pests.

1) Genetic host resistance- use of genetically resistant plants to minimize or avoid losses caused by insect pests and/or pathogens 2) Cultural practices- use of agronomic or horticultural practices that favor plant development and minimize pest or pathogen activity 3) Chemical applications- use of pesticides such as herbicides (weeds), insecticides (insect pests), miticides (mites), antibiotics (bacteria), fungicides (fungi), and nematicides (nematodes) to suppress or inhibit pest or pathogen activity 4) Biological control- use of beneficial or antagonistic organisms that kill or otherwise suppress plant pests or pathogens 5) Government regulatory measures- use of quarantines and post-eradication programs to stop the introduction or spread of deleterious plant pests and/or pathogens

List the steps to scientific inquiry. _____________________________________ ________________________________________________________________________________________________________________________________________________________________________________________________

1) Identify the problem or question and make a hypothesis 2) Test the hypothesis by doing an experiment or a study 3) Check and interpret the results 4) Report the results

Seed germination occurs in three stages. What are they?

1) Imbibition- water uptake 2) Increase in biological activity 3) Radicle (root) and shoot emergence

What are the agricultural uses for gibberellins?

1) Increasing fruit size of seedless grapes 2) Stimulating seed germination and seedling growth 3 Promoting male flowers in cucumbers

List several examples of cultural weed control.

1) Modification of crop planting date 2) Crop row spacing 3) Crop rotation 4) Flooding 5) Use of cover crops 6) Mechanical weed control 7) Use of mulches 8) Use of fire

The disease triangle concept consists of 3 things: __________.

1) Pathogen 2) Environment 3) Host

What are the three methods of herbicide application?

1) Pre-plant- applying before the crop is planted 2) Preemergence- applying after the crop is planted but before crop emergence 3) Postemergence- applying after crop emergence

Most weed-control programs use one or more of the following three strategies—__________.

1) Prevention- restricting introduction or expansion of a weed problem 2) Eradication- complete elimination of weed plants or seeds from an area 3) Reduction of weed plants and seed to a tolerable level

What are the two growing points of the embryo?

1) Radicle- embryonic root 2) Plumule- embryonic shoot

The keys to developing a successful production system are __________.

1) Recognizing and understanding the types of interactions that occur among production factors as well as various yield limiting factors 2) Developing management systems that maximize the beneficial aspect of each interaction

Examples of cold-induced processes include: ________________

1) Seed germination 2) Flowering (The cold induction of flowering is called vernalization) 3) Dormancy breakage 4) Acquisition of cold and freeze tolerance

Complete flowers usually have four parts- _________________.

1) Sepals 2) Petals 3) Stamens 4) Pistil which are usually borne on a receptacle

The carpel or pistil is composed of three parts. List and describe each of them.

1) Stigma- receptive surface that receives the pollen 2) Style- tube connected to the stigma 3) Ovary- attached to the lower end of the style

The stem develops from these three primary tissues produced by the apical meristem.

1) The protoderm 2) The ground meristem 3) The procambium

Name and describe the three soil horizons.

1. A horizon -surface layer -varies in depth -contains most of the plant roots - often lacks some of the important mineral nutrients, but does contain the largest amount of organic matter, which makes the horizon permeable and dark-colored - normally the zone of greatest biological activity in the soil profile 2. B horizon - zone of accumulation - plant nutrients, silts, clays, and other materials are leached into and accumulate in this horizon - generally lighter color than the A horizon - less organic matter is present (although the roots of deep-rooted plants do reach into the B horizon) 3. C horizon - consists of unweathered to slightly weathered material from which the A and B horizons are formed - can also include accumulated calcium carbonates or other salts

The two major processes in soil formation are ___________________________ ________________________________________________________________.

1. Accumulation 2. Transformation of the parent material

Name two ways to protect crops from wind damage. ______________________ _______________________________.

1. Construct windbreaks 2. Grow shelter belts of tall vegetation

Chemical weathering entails four distinct processes. What are they? ________________________________________________________________

1. Dissolution- process by which the constituents of parent material dissolve in water or weak, naturally occurring acids are leached away 2. Hydration- adds molecular water to another compound to form a hydrated material more vulnerable to pulverization 3. Hydrolysis- reaction between a compound and water to form a more soluble product 4. Oxidation- reaction that forms oxides of parent material by reacting with oxygen

List, describe, and give examples of the three types of rocks.

1. Igneous rocks- formed from the hardening of various kinds of molten rock material and are composed of minerals such as quartz and feldspar - Ex: Lava and magma 2. Sedimentary rocks- generally unconsolidated and composed of rock fragments that have been transported and deposited by wind, water, or glaciers - Ex: Limestone, sandstone, and shale 3. Metamorphic rocks- form from igneous or sedimentary rocks that have been subjected to sufficiently high pressures and temperatures to change their structure and composition - Ex: Slate, gneiss, schist, and marble

What factors are responsible for soil formation? __________________________ ________________________________________________________________

1. Parent material 2. Climate 3. Biology 4. Topography 5. Time

Soils consists of 4 components. List each component and define/describe each.

1. Solid fraction- rock fragments and minerals 2. Organic fraction- decayed and decaying residues of plants, microbes, and soil animals 3. Liquid fraction- includes water and dissolved minerals 4. Soil atmosphere or soil air

What are the three functions of roots? _________________________________ ________________________________________________________________

1. Support and anchor the plant stem 2. Absorb water and nutrients 3. Provide storage for food reserves

Agriculture accounts for only about __________ of US energy use, so it can make only _______________________________________________________.

2 percent; a minor contribution to energy consumption

Agriculture accounts for only about ___________ of _______________________ in North America and Europe, it would amount to about ______________ of energy demand in the rest of the world.

2%; energy consumption; 10%

About ________ of pharmaceuticals are _______________________________, and the rest are produced ________________.

25 percent; based on plant products; synthetically

Humans as a race appeared around _______________ years ago and modern man, Homo sapiens, appeared about ____________ years ago.

3 million; 28,000

The pH drops to __________, inhibiting spoilage bacteria and enzyme action, thus __________.

4.2 or below; preventing deterioration

What soil mixture produces a loam soil? _______________________________

40% sand, 40% silt, and 20% clay

About ________________ of the world's population relies on ___________ as its primary energy source, but these same people are mostly in ________________ _______________ and consume _______________________ by US standards.

40%; biomass; undeveloped countries; very little energy

The distribution gap which indicates access to food is projected to rise from ____ ____________________ to more than _________________________________.

44 million tons in 2007; 57 million tons in 2017

Most plants will grow in the pH range of ________.

5 to 7

Cities can be as much as ___________________________________________.

5*C warmer than the surrounding countryside

By _______________ years ago, crops were being grown in Europe and Mexico.

5,000-6,000

The combined value of the ornamental crops is about _____ of the value of corn.

50 percent

A productive soil has _______________________________________________ ________________________________________________________________.

50% pores that will drain water quickly after a thorough watering and 50% that hold water through capillary forces

The estimated _______________ people living in the world depend on cultivated plants _____________________________________________________. The global population ______________________________________.

6.5 billion; for nourishment and to provide quality to their lives; cannot survive as hunters and gatherers

Dry air (absence of water vapor) is comprised of _________________________________________.

78% nitrogen (N), 20.9% oxygen (O), 0.037% carbon dioxide (CO2), and the rest is all other gases

After two centuries of exponential growth, world population shows signs of stabilizing at about _________________________.

9 billion people in 2050

Nearly all of the world's water, __________, is in the ____________ and much of the remainder, ________, is __________.

97.6%; oceans; 2.1%; frozen

List examples of the 5 methods above from the text.

????? Page 301-302 ?????

Define liane. _____________________________________________________

A climbing or twining plant, usually woody

What is an androecium?

A group or whorl of stamens

Define long-day plant.

A plant that flowers when the light period is greater (dark period is shorter) than a critical duration

Define phytochrome. ________________________________________

A reversible protein, red/far-red light sensing pigment occurring in the cytoplasm of green plants. It is associated with the absorption of light that affects growth, development, and differentiation of a plant, independent of photosynthesis

Give an example of how plant roots can physically break down parent rocks. ________________________________________________________________

A tree root growing into a crack in a rock can ultimately fracture the rock.

Define buffering.

Ability of some soil components to resist a change in soil pH

Define parent material. _____________________________________________ ________________________________________________________________

Accumulates from the breakdown of rocks by weathering

Define weather. ___________________________________________________.

Actual values of climatic variables (is not the same as climate)

____________________ is the study of field-grown crops such as wheat, soybeans, corn, forages, and those used for industrial purposes.

Agronomy

Define community. ________________________________________________ ________________________________________________________________.

All the plant populations within a given habitat; usually the populations are considered to be interdependent

Define inflorescence.

An axis-bearing flowers, or a flower cluster (e.g. umbel, spike, panicle)

Define symbiosis. _________________________________________________ ________________________________________________________________.

An obligate relationship between two organisms of different species living together in close association for their mutual benefit

Define saprophyte. ________________________________________________ ________________________________________________________________.

An organism deriving its nutrients from the dead body or the nonliving products of another plant or animal

Define obligate parasite. ____________________________________________ ________________________________________________________________.

An organism that must live as a parasite and cannot otherwise survive

Evaporation from plants involves the process of moving water through the plant and _______________________________________________________________.

And evapotranspiration, often just called transpiration

____________________ is the group of plants to which grasses, flowers, vegetables, fruits, trees, and shrubs belong.

Angiosperms

__________ reproduce by seed only and complete their life cycle within one year.

Annuals

Define protein.

Any group of nitrogen-containing compounds that yield amino acids on hydrolysis and have high molecular weights; They are essential parts of living matter, and are one of the essential food substances of animals

Define lipids.

Any of a group of fats or fat-like compounds insoluble in water, but soluble in certain other solvents

Define genetically modified organism (GMO).

Any organism that is the product of genetic recombination, which includes almost all organisms except those produced clonally or parthenogenetically. Sometimes different species, such as plant and bacteria, can exchange genetic material, for example, wheat. Includes, but is not limited to, genetically engineered organisms

Define pasture.

Area of domesticated forages, usually improved, on which animals are grazed

When light intensity is too low for adequate photosynthesis, ______________________________________.

Artificial light can be used

The sensing of light for photoperiodic and other photomorphogenic responses occur _______________________________________________.

At much lower light intensities than are needed by most plants for photosynthesis

The intensity of solar radiations is highest __________________ and decreases at ________________________________ for two reasons, both relating to the _________________________________________.

At the equator; higher and lower altitudes; angle at which the radiation is received

Define microclimates. ______________________________________________ ________________________________________________________________________________________________________________________________

Atmospheric environmental conditions in the immediate vicinity of the plant, including interchanges of energy, gases, and water between atmosphere and soil

___________________ were the first group of plant hormones to be discovered.

Auxins

What is the most abundant soil organism? ______________________________

Bacteria

__________ are microscopic, single-celled organisms.

Bacteria

Why have grasslands been the most extensively modified biome? ________________________________________________________________

Because of their value for agriculture

__________ live for two years and reproduce only by seed.

Biennials

What are the two types of biofuels? ___________________________________

Biodiesel and ethanol

What is the advantage of biofuels over fossil fuels? ______________________ ________________________________________________________________________________________________________________________________.

Biofuels are renewable and they sequester CO2 during their growth cycle, thereby reducing the carbon footprint

__________ involves introduction of a living organism, often a natural pest or disease, to control a weed species.

Biological weed control

Define salicylic acid.

Biologically active component of aspirin?????

____________________ is a recent, but major threat to agriculture.

Bioterrorism

What are the signals that trigger the action of the regulatory genes?

Biotic signals: - Plant hormones - Certain inorganic ions - coenzymes - Other metabolites

Define eutrophication.

Build up of plant nutrients in a body of water that increases plant growth, especially algae, and often results in hypoxia (reduced oxygen) that is needed for aquatic animals to survive.. The hypoxia results from the respiration of the densely growing plants, especially at night when they are not photosynthesizing, and decomposition of the plants when they die.

_________ are highly compressed underground stems to which ______________________. Examples: _________________

Bulbs; numerous storage leaves (scales) are attached

___________________________________________________ in preparation for agriculture or other development also contributes to ____________________.

Burning of forests and other natural vegetation; airborne particulates

What is the term for the sepals collectively?

Calyx

What happens in the zone of elongation?

Cells expand (especially in length), new protoplasm forms, and the size of the vacuoles increases

________________ is the basis of many of the fibers that we use for clothing, rope, and the like.

Cellulose

Define shade avoidance response.

Change in growth in response to overcrowding among plants, most notably an increase in stem length, thinner stems, as well as larger, thinner leaves

Photosynthesis occurs in _________________.

Choloroplasts

______________ is the main influence on the type of __________ that develops.

Climate; vegetation

The emerging plumule is protected by a sheath-like leaf, the ________________ that __________.

Coleoptile; envelopes the main stem as it grows upward through the soil

_____________________________ gives support to young stems, petioles, and the ______________________________.

Collenchyma tissue; veins of leaves

Define plastids.

Colorless leukoplakia that serve as storage bodies for oil, starch, and proteins

Define chlorophyll.

Complex organic molecule that traps light energy for conversion into chemical energy through photosynthesis

Define starch.

Complex polysaccharide carbohydrate; form of food commonly stored in plants

Define humus.

Complex, amorphous, and colloidal substance that remains after decomposition and is resistant to further decomposition

_____________ make up the dominant vegetation in this boreal forest, or _____, and plant diversity is _______________________________________________.

Coniferous trees; taiga; much lower than in the temperate and tropical forests

Define vascular system.

Consists of the pericycle, phloem, vascular cambium, xylem, pith rays, and pith?????

__________ refers to the materials that enter the insect or mite body directly through the pest's cuticle.

Contact poison

_______________ allow for the comparison needed to ____________________ _____________________.

Controls; draw conclusions about treatment effects

____________________ occurs commonly in the bark of maturing stems, the trunks of trees, and ___________________.

Cork tissue; potato skins

__________ are thickened compressed stems that grow _____________. Examples: _______________________

Corms; underground; Gladiolus, crocus, and freesia

What is the most important and best-known plant fiber crop? ________________

Cotton

______________________________ have one or a few species that do not ________________________________________________________________.

Crop ecosystems; exploit all of the resources of the environment

__________ describes any method of crop production that enhances the capacity of a crop to compete with weeds

Cultural weed control

Which group of plant hormones primarily promotes cell division but also participates in a great many aspects of plant growth and development?

Cytokinins

_______________ is the branch of biology involved in the study of the components of cells and their functions.

Cytology

What is the most common maturity rating system in the United States?

Days-to-maturity system

Moving toward the poles, the angle of approach __________________________________________________. The result is that the ____________ at noon at 40°N is _________________________________________.

Decreases towards zero so that light travels further through the atmosphere and spreads over a wider surface area; intensity; about 60% of the value at the equator

Define photomorphogenesis.

Describes several highly integrated processes that are regulated to produce the shape or form of the plant, and they include seed germination in light-sensitive seeds. de-etiolation (greening of young seedlings when they emerge from the soil), and stem growth in plants competing for light with other plants

What is the largest biome? ______________

Desert

__________ are chemicals or materials that can cause insects to lose water faster than they can replace it.

Dessicants

__________ is the study of insects.

Entomology

___________________________________ (EPA) data imply that ___________ ________________________________________________________________.

Environmental Protection Agency; more pesticides, mostly herbicides, are applied to lawns than to agronomic crops

____________________, the study of plant usage by _____________________ ________________________________________________________________, has become an important branch of plant science.

Ethanobotany; indigenous cultures and the preservation of that knowledge about plants

________________________________ are made up of compartments bounded by membranes, with specialized structures and functions.

Eukaryotic cells

Define morphology.

External form of the plant

____________________ promotes stem elongation so the low _____________ ____________________________.

Far-red light; R:FR account for the spindly growth

__________ are thick-walled sclerenchyma cells that provide support.

Fibers

How can land be desalinated? _______________________________________ ________________________________________________________________

Flooding the land with water and leaching the salts downward through the soil profile

Define flower.

Floral leaves grouped together on a stem that, in the angiosperms, are adapted for sexual reproduction

Define florigen.

Floral stimulus (suspected of being a protein) that promotes flowering

Define forb.

Flowering herbaceous plants that are not grasses, sedges, or rushes

What are perfect flowers?

Flowers with both stamens and pistils

Define pistillate flowers.

Flowers with pistils, but no stamens

Define staminate flowers.

Flowers with stamens, but not pistils

What are the reproductive parts of the plant?

Flowers, fruits, and seeds

__________ are the edible parts of plants, primarily the __________ that can be fed directly or following storage to livestock.

Forage, browse, or herbage; leaves and digestable stems

_________________ starts with pollination, which is the transfer of pollen from an anther to a stigma in angiosperms.

Fruit, grain, and seed formation

Define biofuel. ____________________________________________________

Fuel that is produced from recently living organic matter

____________________ are transcribed from the DNA in the nucleus and translated into proteins on the ________________.

Genetic codes; ribosomes

What does GMO stand for? _________________________________________

Genetically modified organism

What type of plants accumulate nutrients in the roots and stems that are renewed from year to year? ___________________________

Grassland plants

_______________ accounts for ________ of the total, while only _____ exists as _______________________________________.

Groundwater; 0.3%; 0.01%; fresh water in lakes and streams

_________________ are a way to measure heat accumulation.

Growing degree days (GDD)

Define apical meristem.

Growing point that lies between the cotyledons and is flanked by two opposite primary foliage leaves

Organisms, including humans that cannot synthesize those compounds are called ________________.

Heterotophs

_____________________________ (HID) lights are the only type of artificial light source currently available that ________________________________________.

High intensity discharge; can be used in greenhouses to promote growth of high-value crops when natural light intensity or duration is too low

The world's terrestrial ecosystems can be divided into three broad groups ________________________________________________________________.

High, intermediate, and low photosynthetic productivity

What determines a microclimate? _____________________________________ ________________________________________________________________________________________________________________________________

Hills, valleys, small depressions in a field, proximity to large and small bodies of water, presence of large land masses or buildings

Define hypocotyl.

Hook of the bean

Define plagiotropic growth.

Horizontal growth

_______________ is the study of crops that require more intense and constant care, from planting through delivery to the consumer.

Horticulture

What is a flower lacking either stamens or pistils called?

Imperfect flower

How are biomes described? _________________________________________ ________________________________________________________________

In terms of the vegetation that existed before human interference

__________ are applied as fumigants and inhaled as a vapor or dust by the insect or mite, and the material is then absorbed through the respiratory system.

Inhalants

What causes soil horizons? _________________________________________ ________________________________________________________________

Interactions between biological and chemical agents reacting with parent material over long periods of time differentiate the soil into horizons.

_____________________________ are active tissues that have been separated from the apical meristem by regions of more mature or developed tissues.

Intercalary meristems

Define middle lamella.

Intercellular later that contains many of the mucilaginous pectin compounds that hold adjacent cell walls together

__________ consists of simultaneously producing two or more crops in the same field.

Intercropping

Define histology.

Internal structure of the plant (microscopic features)

Define plant growth.

Irreversible increase in volume or dry weight (biomass)?????

_______________ has a long history and allows us to grow many ____________.

Irrigation; crops in areas that otherwise would be unsuitable for growing

Define grazing land.

Land that is suitable for use as pasture for animals though it may not be suitable for growing other crops

Define xeriscape.

Landscapes that are designed to reduce or eliminate the need for irrigation

Define biome. ____________________________________________________ ________________________________________________________________________________________________________________________________.

Large terrestrial ecosystem characterized by specific communities, usually named after the predominant vegetation found there (ex: temperate forest)

Define tissue.

Large tracts of organized cells of similar structure that perform a collective function

Define trifoliate.

Leaf with three leaflets attached at the same point (ex: bean plant or clover)

Define photoperiod.

Length of day or period of daily illumination required for the normal growth and sexual reproduction of some plants

__________ is the stages an organism goes through from fertilization to death.

Lifecycle

The light intensity at which photosynthesis and repiration rates are equal is called the ______________________________.

Light Compensation Point

____________________ does not refer to how beneficial the light is for the plant, but rather to ______________________.

Light quality; the relative quantity of individual component wavelengths contained in an incident beam of light

Define visible light.

Light with a wavelength of 400-700 nm, which is the range visible to the human eye

__________ is the breaking or collapse of stalks or stems usually at or near maturity.

Lodging

Plants that flower when the light period exceeds a critical length are called ___________.

Long day plants

Define transpiration.

Loss of water from a leaf by evaporation

____________________________ can be used to decide when to sow seeds and to select areas suitable for fruit production. Other maps can show the _____________________________.

Mapping showing expected dates of last frost; expected dates of first frost in the autumn

__________ are important factors to consider in variety selection for all crops.

Maturity, yield potential, and insect and disease resistance

_______________ or ____________________________ is comprised of actively dividing cells that develop and differentiate into yet other tissues and organs.

Meristem; meristematic tissue

Define vascular cambium.

Meristems that produce new xylem (water and mineral conducting elements) and new phloem (photosynthate conducting elements), and the cork cambium (produces bark)

____________ are sites of respiration and are also involved in protein synthesis.

Mitochondria

Define deoxyribonucleic acid.

Molecule that contains genetic information coding for all cell functions

Define pigments.

Molecules that are colored by the light they absorb; Some plant pigments are water soluble, and are found mainly in the cell vacuole

__________ is growing the same crop in a field continuously over a period of years.

Monoculture

Plants having both staminate and pistillate flowers on the same plant are called ____________. If the pistillate and staminate flowers are borne on separate individual plants, the species is called ____________________.

Monoecious; dioecious

What has to happen to allow the family farm to remain viable? ______________ ________________________________________________________________ ________________________________________________________________

New uses for old crops and production strategies for new crops will have to be developed.

_________________________ plants are important for maintaining the nitrogen supply in natural ecosystems.

Nitrogen-fixing

Define Rhizobioum.

Nitrogen-fixing bacteria that has a symbiotic relationship with the plant

__________ involves pasture establishment without tillage of the soil.

No-till planting

__________________________________________________ provide the plants for the urban environment.

Nurseries, greenhouses, and sod farms

____________ are passed continuously from one organism to another along with the _______________________________________ that sustain the whole ecosystem and that ________________________________________________.

Nutrients; energy and carbon compounds; originally came from plants

_____________________ does not allow the use of __________ and certain types of _______________________________________.

Organic farming; GMOs; chemicals for pest control and fertilization

________________________ contains reserves of nutrients and makes up a large part of the _________________________ that are characteristic of _________________________ around the world.

Organic matter; black earths; moist grasslands

Define autotrophs. _________________________________________________ ________________________________________________________________

Organisms that can synthesize their own food from inorganic compounds via a process called photosynthesis

Define heterotrophs. _______________________________________________ ________________________________________________________________

Organisms that depend on the compounds synthesized by autotrophs for nourishment

How can arid lands be turned into desert? ____________________________

Overgrazing

_____________ are organisms that derive their nutrition by ________________ ______________________________________, often _____________________ _________________________________ such as swellings or discolored tissue.

Parasites; living in or on the tissues of another organism; producing symptoms of disease

________________ is a long-term relationship between ___________________ _____________, in which the host ____________________________________ ________________________________________________________________.

Parasitism; a host and a pathogen; does not usually die because this would also entail the death of the pathogen

___________________________________ is made up of living thin-walled cells with large vacuoles and many flattened sides.

Perenchyma tissue

__________ can interfere with an insect's normal nervous system functions.

Pesticides

The chemicals that insects normally use to communicate with each other are called __________.

Pheromones

_______________________ are thick-walled cells that provide _____________.

Phloem fibers; stem support

_______________ conducts food and metabolites from __________________________________.

Phloem; the leaves to the stem, flowers, roots, and storage organs

For most plants, ____________________ cannot occur without simultaneous ____________________.

Photosynthesis; transpiration

Physical weathering is ____________________________________.

Physical breakdown of large pieces of rock into smaller and smaller pieces

Define short-day plant.

Plant that initiates flowers only under short-day (long night) conditions

Define day-neutral plant.

Plant that is capable of flowering under either long or short daylengths

_________ are consumed by a wide range of animals, which we call _________.

Plants; herbivores

__________ are the key components of the _______________ and influence ________________________________________________________________.

Plants; soil ecosystem; all of the other organisms present

As water vapor escapes through _____________________________________, the carbon dioxide needed for photosynthesis ____________________________.

Pores in the lead surface called stomata; enters the lead through the pores at the same time

__________ are applied directly to foliage after weed emergence.

Postemergence herbicides

__________ are applied to soil after crop planting but prior to the emergence of the weeds, crops, or both.

Preemergence herbicides

__________ are applied before the crop is planted.

Preplant herbicides

Define climate. __________________________________________________.

Prevailing weather conditions of an area

List the categories of organisms found in all terrestrial ecosystems. __________ ________________________________________________________________ ________________________________________________________________

Primary producers, herbivores, parasites, commensals, detritovores, and saprophytes

Define exfoliation.

Process of the cracking ad peeling of the outer layers of rocks through differential rates of contraction and expansion caused by temperature changes?????

What are the two types of cells?

Prokaryotic cells and eukaryotic cells

_________________________________ have no separate subcellular units. Ex: _______________

Prokaryotic cells; nuclear material is not enclosed in a membrane

Define nucleus.

Prominent organelle within the cell that is enclosed by a double membrane and contains one or more bodies called nucleoli

Define coleorhiza.

Protective sheath from which the primary root develops and the secondary roots branch

Define seed coat or testa.

Protective tissue derived from the integuments that cover a seed

Define transcription factors.

Proteins that regulate the activity of structural genes and other regulatory genes

What is one aspect of climate that can be and is modified on a large scale?

Providing water in order to grow crops where natural precipitation is inadequate during some or all of the growing season

Define photosynthetic active radiation.

Radiation in the 400-700 nm spectral waveband

________________ is a serious pathogen of several of our food crops. The potential of the fungus to ____________ those crops is the reason it has been ________________________________________.

Ralstonia; devastate; listed as a bioterror organism

Define relative humidity (RH).

Ratio of amount of water vapor in the air compared to what the air can hold at that temperature (see also saturated vapor pressure, or SVP)

Define vegetative growth.

Referring to asexual (stem, leaf, root) development in plants in contrast to sexual (flower, seed) development (Includes roots, shoots, and leaves, but not reproductive structures, such as flowers and seeds)

Radiation passing through the earth's atmosphere can be ________________________, resulting in significant reflection of light back into outer space and thus __________________________.

Refracted or scattered; reducing the amount of light available for photosynthesis

Define cyme.

Resembles the corymb (Short flat-topped flower with an indeterminate cluster that continues to produce flowers until conditions become unfavorable), except that the central or topmost flower is the first to open

__________________ and __________________ landscaping is a business that generates billions of dollars annually in the United States alone.

Residential; commercial

Define photoperiodism.

Response of a plant to the relative lengths of day and night (light and dark), particularly in respect to flower initiation and bulbing

Define fibrous root. Give examples.

Roots that branch in many directions; grasses, grain crops, and many kinds of shallow-rooted trees

Define adventitious roots.

Roots that form at any place on a plant tissue other than the radicle of a germinating seed and its extensions

What are the vegetative parts of the plant?

Roots, stems, and leaves

What parts make up the plant body? __________________________________

Roots, stems, leaves, flowers, fruits, and seeds

__________ (sheep, goats and cattle) have four digestive chambers, the first of which (the rumen) is filled with __________.

Ruminants; microorganisms that digest and break down forage fiber

After the soil is saturated, the excess water _____________________________.

Runs off or drains away

_______________________ or the _______________________ is the systematic approach to understanding and solving a problem.

Scientific inquiry; scientific method

_________________________________ is composed of thick-walled cells found throughout the plant as fibers or _______________.

Sclerenchyma; sclereids

__________ and the vigor and timing of planting are major factors that need to be considered when determining __________.

Seed germinability; the seeding rate required to acheive a target plant population

What are albuminous seeds?

Seeds having a large portion of their food stored as endosperm

What are exalbuminous seeds?

Seeds with no endosperm, or only a thin layer surrounding the embryo

__________________ is considered to be a terminal, irreversible ____________ in living organisms, leading to cellular and tissue breakdown and __________.

Senescence; deteriorative change; death

What are the accessory flower parts?

Sepals (calyx) and petals (corolla)

____________________ are those that flower when the light period is less than a critical length.

Short day plants

Define corymb.

Short flat-topped flower with an indeterminate cluster that continues to produce flowers until conditions become unfavorable

_______________ members are long slender cells with ____________________ called sieve plates.

Sieve-tube; porous ends

Define microclimate. ______________________________________________.

Similar, smaller effects caused by buildings, ponds, or ground depressions contribute to it?????

Define spring ephemerals. __________________________________________ ________________________________________________________________________________________________________________________________

Small flowering plants that grow in deciduous forests that start and complete their annual lifecycle in a very short time in the spring before trees leaf out

Define stoma (stomate).

Small opening (bordered by guard cells) in the epidermis of leaves and stems, through which gases (including water vapor) pass

Why do malnutrition and starvation exist in both developed and undeveloped countries? _______________________________________________________ ________________________________________________________________

Social and political issues prevent the distribution of food to those who need it

__________ are those in which fibers are located in the stems or, more precisely, in the outer phloem tissues of the bark. Examples: __________

Soft of bast fibers; flax, hemp, jute, kenaf, and ramie

________________ can be a devastating consequence of attempted cultivation.

Soil erosion

What is the most important management tool for the control of forage production?

Soil fertility

________________________ is defined as the percentage of sand, silt, and clay particles in a soil.

Soil texture

____________________ determines or influences all of the other variables that _____________________.

Solar radiation; make up climate

Climate includes the intensity and duration of ____________________________ ___________________________________________ that may be expected; and how these _______________________________________________________.

Solar radiation; temperature; rainfall; wind speed and direction; characteristics vary according to season

Define organelle.

Specialized region in a cell that is bound by a membrane (Ex: mitochondria)

What are the essential parts of the complete flower for sexual reproduction?

Stamen ad pistils

__________ are stems that grow horizontally _____________, sometimes called __________. Examples: ___________________

Stolons; above ground; runners; ajuga, Bermuda grass, and some ferns

__________ refers to the materials that enter the insect by mouth, and kill by being absorbed into the body through the digestive track.

Stomach poison

_______________ are payments that are supposed to help farms stay in business, but end up as one more factor encouraging consolidation in the industry.

Subsidies

____________ is the most common form of sugar transported in the plant and is the sweetener that we commonly call _____________________.

Sucrose, table sugar

____________ are materials generally act by slowing, but not stopping, cell division and elongation in subapical meristems, usually without causing stem or leaf malformations.

Synthetic growth retardants

What is the second largest biome? _______________

Taiga

Define dew point.

Temperature at which water vapor condenses from the air

What is the major function of greenhouses? _____________________________

Temperature manipulation

_________________ strongly influences fruit set. Temperatures that are ______________ at this critical period are often responsible for _____________.

Temperature; too low or too high; crop failures

Define sustainability. _______________________________________________ _______________________________________.

The ability to be maintained with little input of nonrenewable resources

Define angle of incidence.

The angle that a beam of sunlight makes with the Earth's surface

Define determinate growth.

The flowering of plant species uniformly within certain time limits, allowing most of the fruit to ripen about the same time

Define indeterminate growth.

The flowers of plants are born on lateral branches, the central stem continues vegetative growth, with blooming continues for a long period Ex: Alfalfa and fuchsia

What is the first step in the development of soil?

The formation and accumulation of material by chemical and physical weathering of parent rocks

Define human footprint. _____________________________________________ ________________________________________________________________

The impact that human activity has on ecosystems and global resources

Define carbon dioxide compensation point.

The level of carbon dioxide available to the leaf for photosynthesis equals the amount of carbon dioxide generated by the plant's respiration. Photosynthesis cannot increase unless the amount of available carbon dioxide is increased by further respiration.

Define Calvin Cycle

The non-light requiring reaction in photosynthesis where carbon fixation occurs. The energy from the light reaction provides the energy for the Calvin Cycle.

Define harvest index. ______________________________________________ ________________________________________________________________

The percentage of a plant's biomass that is incorporates into the harvestable plant

Define photosynthesis

The process in green plants of converting water and carbon dioxide into sugar with light energy, accompanied by the production of oxygen

Define Carbon Cycle

The recycling of carbon through the process of photosynthesis and respiration

Define climax community. __________________________________________ ________________________________________________________________

The stable community of plants and animals that results from a complex community replacing simpler ones

_________ are long, tapered, dead cells that conduct water through ______ and contribute significant _______________________________________________.

Tracheids; pits; strength and support to the stems of the gymnosperms

_______________ in grassland and savanna is limited to some extent by ______ ________, but ____________________________________________________ ______________________.

Tree growth; lack of water; fire and grazing animals are also important in maintaining these ecosystems

Define orthotropic growth.

Upright growth

____________ populations have increased in every US state.

Urban

Define independent variable. ________________________________________ ________________________________________________________________

Variable in an experiment that is manipulated to evaluate its effect on another (dependent) variable in an experiment

Define dependent variable. __________________________________________ ________________________________________________________________

Variable that is measured or evaluated as the result of a change in another (independent) variable in an experiment

Define by-pass growth.

Vegetative growth that occurs if the switch in reproductive growth is interrupted Ex: In poinsettias if long days (vegetative photoperiod) follow several short days (reproductive photoperiod)

Define soil profile. _________________________________________________ ________________________________________________________________

Vertical section of soil extending through all its horizons from the surface to the parent material

_______________ are long tubes made up of ___________________________ that are joined end to end after the end walls of the cells ___________________.

Vessels; short vessel members; have dissolved

__________ are intracellular pathogenic particles that infect other living organisms.

Viruses

Define pore spaces. _______________________________________________

Voids found between the solids

_______________ are the two carriers for ______________________________.

Water and air; convective heat transfer

Define field capacity. _______________________________________________ ________________________________________________________________

Water that is left after gravity has removed as much as it can

Spindly growth results in a _______________, but by rapidly growing tall, the plant can ____________________.

Weaker plant; become taller than its neighbors and begin to capture more light for photosynthesis and become stronger

When is a plant saturated?

When further increases in light intensity increase photosynthesis little or not at all

For greenhouse plants, why is it beneficial to provide physical stimulation by creating air movement with fans or brushing the foliage on a regular basis? ___________________________________________

Without wind disturbance, the plants might become tall and weak-stemmed

_______________ is a structurally complex tissue that conducts water and dissolved minerals ________________________________________________.

Xylem; from the roots to all parts of the plant

The increasing combustion of fossil fuels and the clearance of natural vegetation on all continents have caused ______________________________________.

a 30% increase in atmospheric carbon dioxide over the past two centuries

An ecosystem consists of ___________________________________________.

a community of organisms in a physical environment

Hydrolysis is the reaction between ____________________________________ ________________________________________________________________.

a compound and water to form a more soluble product

When the people of a country become more affluent, they want and can afford to purchase ________________________________________________________ ________________________________________________________________.

a greater proportion of their protein in the form of the more palatable animal products- steaks, chops, eggs, processed meats, and dairy products

Hydration adds molecular water to another compound to form _______________ ________________________________________________________________.

a hydrated material more vulnerable to pulverization

A plant hormone is ___________ that acts to control plant activities.

a natural substance produced by the plant itself

Niches exist when _________________________________________________ ________________________________________________________________.

a resource is partitioned so that different portions of it are accessible to only certain species

Simple fruits have __________________.

a single ovary formed from one flower

Environmental and plant growth factors that affect the rate of photosynthesis are:

a. Light Quality b. Light intensity c. Carbon Dioxide concentration d. heat e. water availability f. Plant development

Land plants account for _______________________________________, which keeps the balance between _________________________________________.

about 60% of global photosynthesis; oxygen and carbon dioxide about 600 to 1

Root hairs actively ________________________________________.

absorb water from the soil

Roots are responsible for ______________________________________________.

absorbing and conducting water and mineral nutrients and for anchoring and supporting the plant

Air tends to move ________________________________________.

across the top of the canopy rather than through it

Relative humidity is expressed as the ___________________________________ relative to the maximum amount that the air can hold _____________________________, which is known as the ______________________________________________.

actual water content; at a given temperature; saturated vapor pressure (SVP)

Define ecotypes.

adaptation differs from other members of the same species?????

They produce energy rich compounds such as __________________________.

adenosine triphosphate (ATP)

These crops with purely ____________________ are produced in about 6,800 hectares of ____________________ and 280,000 hectares of ______________, which corresponds to about _________________________________________ ________________________________________________________________.

aesthetic value; greenhouses; open area; 0.15 percent of the U.S. crop area, or about 1 percent of the area used for corn

The _______________ and _______________ use of plants is important in urban and suburban areas.

aesthetic; recreational

Tomatoes grown for processing and turfgrass are examples of crops that can be designated _______________ or _______________.

agronomic; horticultural

Silos for silage must be __________ structures and are either __________.

airtight; vertical or horizontal

A single species cannot utilize _______________________________________ ________________________________________________________________.

all of the resources or the whole of any one resource in the environment

Worldwide, more land is devoted to grasslands than __________ and totals __________.

all other crops combined; 26.1% of the world's land area

Climate is modified by local features such as ____________________________.

altitude, presence of land or water, and barriers to air circulation

Parasitoids are ___________________________________________________ ________________________________________. When they emerge as adults __________________________________.

animals, often insects, that spend the juvenile phase of their lifecycle in the tissues of another insect; the host is killed

Winter temperatures are relatively unimportant for _______________, which survive the winter season ____________________.

annuals; as seeds

Once flowering is induced for whatever reason, there is a change in the ________________.

apical meristem from vegetative (producing shoots and leaves) to reproductive (producing floral parts)

Groundwater can accumulate in natural underground reservoirs called ________.

aquifers

A population can be defined _________________________________________ ________________________________________________________________.

as all of the individuals of a species that inhabit a particular environment

Nearly all of the earth's nitrogen is in the _______________________________.

atmosphere or in the lithosphere (rock and soil)

Heterotophs must consume ____________________________________________ in order to get the energy-releasing carbohydrates.

autotrophs or other heterotophs that have fed on autotrophs

Organisms such as plants and the bacteria that can photosynthesize are called ____________ because _________________________________________________________.

autotrophs, they can synthesize the compounds that release energy during respiration

Plant stems generally produce buds in the ________________.

axils of leaves at the nodes or terminally on shoots

Silage is moist forage, preserved by __________.

bacterial fermentation under anaerobic conditions

Cultivated grains and grasses, fruits, vegetables, and ornamentals have _______ ________________________________________________________________.

become dependent on human intervention to survive

A species has a minimum temperature, ________________________________; an ______________________________ for growth; and a maximum temperature, ______________________________________________.

below which growth does not occur; optimum temperature; above which injury occurs

Circadian rhythms are ________________.

biological rhythms that complete one cycle in approximately 24 hours

In most dicotyledonous plants, the leaf is made up of the __________, the _____________ part; the stem like __________, which attaches the __________________; and in some plants the __________ at the __________________.

blade; flat thin; petiole; blade to the stem; stipules; base of the petiole

In addition to causing loss of soil, the dust cloud can ______________________.

block the sunlight

Define anthocyanin.

blue or red pigments

The way that we define the environment determines the ___________________ ________________________________.

boundaries of the population

The petals are usually _________________________________, and they often contain __________________, which pollinate the flowers.

brightly colored, with some yellow; nectaries that secrete nectar to attract insects

Also called __________ and __________ applies seed directly to existing vegetation.

broadcast seeding; oversowing, frost seeding

In winter, ________________________ to the surrounding environment. In summer, buildings and paved surfaces _________________________________ _______________________________ over time.

buildings radiate heat; absorb solar radiation and release it as so-called sensible heat

Plants that have underground stems with only a small portion of the stem showing for a relatively short period in the spring are called ________________.

bulbous plants

Families can enjoy a visit to the local farm to ________ or ________ their own produce. This interaction may help maintain ____________________________ ________________________________________________________________.

buy; pick; contact and understanding between the mass of the population and the few remaining farmers

The oxygen in the atmosphere that we depend on for our survival is produced _________________________________.

by plants and algae during photosynthesis

Meristematic tissues are found in woody perennials as cylinders in the shoots and roots, also known as the _____________________________.

cambium layer

Temperate oil crops, such as ___________________________ are used in the manufacturing of _______________________________________.

canola and soybean; lubricants and plastics

Plants help to prevent runoff and encourage infiltration partly by _____________.

capturing water on their surface, this slowing the passage of water to the soil

A healthy diet requires an energy source such as ________________________ ________________________________________________________________.

carbohydrate, or fat, protein. linoleic acid, and various vitamins, minerals, and water

The radiant energy is used to synthesize carbon based molecules called __________ from ______________ and __________, releasing ___________ in the process.

carbohydrates, carbon dioxide (Co2), water (H2O), oxygen

The ____________________________________ ratio is nearly constant at about _________________ of carbon to _____________ nitrogen, worldwide.

carbon:nitrogen (C:N); 12 parts of carbon to one part nitrogen (12:1)

Each ovary develops into a fruit, called a _______________, which ________________________.

caryopsis; encloses the true seed

The _______________ is a spike with only pistillate or staminate flowers.

catkin

The ____________ protects the protoplast, provides an ___________________, and in some tissues may act as a _____________________________________.

cell wall, external structure; strong support for the plant

It may be necessary to use __________________________________________ __________________________________________.

chemicals, introduced predators and parasites (biocontrols, or other means to control slugs, insects, rodents, birds, or deer)

Chromoplasts with chlorophyll are called ____________________ and are responsible for ___________________________________.

chloroplasts; photosynthesis in leaves and in some stems

Within the nucleus are the _________________________, long lengths of deoxyribonucleic acid (DNA).

chromosomes

Tropical oil crops, such as ___________________________________ are the main sources of oils used in _________________________________________.

coconut and palm oil; soaps and detergents

A more general term for a mutually beneficial association between organisms is _______________________________.

commensalism

In the desert, fertilizers must be used to ________________________________ ________________________________________________________________.

compensate for the low fertility of the soils

Tissues of various types combine to form _______________________________ such as ________________________________.

complex plant organs, such as leaves, flowers, fruits, stems, and roots

Forage crops are often __________ and fed later to livestock.

conserved or preserved

Most of the energy used for our food supply is ___________________________ ________________________________________________________________.

consumed )for transportation, processing, and storage) after produce leaves the farm

Worldwide food scarcity in the years ahead is a real possibility unless measures are taken to __________.

control population and increase food production

Plants are essentially the only terrestrial organisms that ___________________ ________________________________________________________________________________________________________________________________.

convert inorganic carbon, oxygen, hydrogen, nitrogen, and sulfur to organic forms through photosynthesis

Soil bacteria, both free-living and in association with plant roots, _________________________________________.

convert nitrogen to ammonia

Photosynthesis is the process of ___________________________________________________.

converting light (radiant) energy to chemical energy in the form of reduced carbon compounds

The better-known uses of plant oils are __________.

cooking, flavoring, margarine, and salad dressings

The ___________ produces bark, the protective covering of old stems and roots.

cork cambium

The collective term for petals is _______________.

corolla

This is the principal tissue of the cylindrical zone under the epidermis extending inward to the phloem is a region called the _______________.

cortex

Soil fragments vary in size from _______________________________________ ________________________________________________________________.

course rock fragments (> 2 mm) to those so small that an electron microscope is needed to observe them (< 0.002 mm)

Some of the earliest products of the industrial revolution were farm implements for _________________________.

crop cultivation

Increased food production must come primarily from __________.

crop plants with high caloric output per unit area of land

Detritovores and saprophytes may be less important in crop ecosystems than in nature because ___________________________________________________ ________________________________________________________________.

crops and crop residues are removed and the nutrients are replaced by synthetic fertilizers

Agricultural research made new cultivars or ____________________________ of high-yielding ___________________________, and other crops available to highly populated developing countries.

cultivated-variety; wheat, rice, corn

Humans began the purposeful growing or ____________________ of plants to improve the supply of materials obtained from these plants.

cultivation

Much of the world's best agricultural land is already under _______________, although there is still ______________________________ awaiting development in Argentina, Brazil, Canada, Sudan, and Australia.

cultivation; unused productive land

The ____________________ is a viscous fluid composed of matrix proteins, bounded by the semipermeable plasma membrane.

cytoplasm

Many soil organisms are involved in __________________________________ in soil organic matter.

decomposition and recycling of nutrients

In the United States, even though the number of farms is __________________, the size of farms is ____________________.

decreasing; increasing

The demand for food and fuel is leading to ________________ in many tropical countries.

deforestation

Saprophytes are aided in their activity by _______________________________ ________________________________________________________________.

detritovores that break up large pieces of organic matter as they consume it

In fleshy fruits the entire pericarp and accessory parts ____________________.

develop into succulent tissue

Winds are driven by ____________________________________ resulting from corresponding differences in the _____________________.

differences in air pressure; input of solar energy

Wind can be a major cause of damage to crops, either because of ___________.

direct physical damage or excessive transpiration

Light intensity is ______________________.

directly related to plant photosynthetic rates

A __________ is defined as suboptimal plant growth brought about by continuous irritant such as a pathogen or via chronic exposure to less than ideal growing conditions.

disease

The __________________________ of herbivores emphasize the importance of __________________________________________________.

diversity and large numbers; plants as a food source in terrestrial ecosystems

If light is not limiting, the rate of photosynthetic activity ___________________ for each ____________ increase in temperature for many plant species, up to a point.

doubles, 10 degrees Celsius (18 degrees f)

GMOs have been created that ________________________________________ __________________________.

dramatically reduce the need for pesticides and field tillage

Forest clearance tends to lead to _____________________________.

drier climates

Plants are the source of many ______________________________.

drugs and medicines

In dry-fleshy fruits, some parts of the pericarp become ____________________.

dry and other portions remain succulent

Forages are conserved in two primary forms: __________.

dry hay or moist silage

The short melt period in the summer allows only a low vegetation of __________ ______________________________________________________.

dwarf shrubs, sedges, and grasses to develop

The major energy input for the earth comes as ________________________________.

electromagnetic radiation from the sun

The __________ is a miniature plantlet formed within _______________________.

embryo; the seed from the union of the male and female gametes during fertilization

Odum's concept of embodied energy, or ____________, is the amount of solar energy represented in the resource or commodity.

emergy

A single layer of inner cortical cells forms the ____________________, a tissue found only in the root and not the stem.

endodermis

Proteins are synthesized on the surfaces of the __________________________, on small discrete structures called _______________.

endoplasmic reticulum (ER); ribosomes

Much of our footprint is related to _________________________.

energy use

Stem tubers are the ___________________ of underground stems. Example: ___________________

enlarged, fleshy, terminal portions; white potato

It is important to supply water efficiently so that __________________________ and as little as possible is lost through _________________________________.

enough reaches the plant roots; evaporation, runoff, or drainage

The stem region just above the cotyledons and below the first trifoliate leaves is called the __________________.

epicotyl

Root hairs, which are an extension of the _______________ are the site of _________________.

epidermal cells of young roots; most water and nutrient absorption

The _______________ is a single exterior layer of cells that protects stems, leaves, flowers, and roots.

epidermis

The protoderm gives rise to the _________________; the ground meristem gives rise to the _______; the procambium gives rise to the _____________________.

epidermis; cortex; vascular cambium

At the ____________, the angle of the sun is always close to _______________ __________________. The radiation travels ____________________ through the atmosphere and reaches the _________________________________.

equator; 90* relative to the earth's surface; the least distance; minimum surface area

Some organic farming practices, such as _______________________________ may have _______________ environmental impact.

erosion from soil cultivation; negative

Plant cells are ___________________________.

eukaryotic cells

In healthy, natural ecosystems, ______________________________, and consequently ___________________________________. It is difficult for new species to colonize the environment because it __________________________ ________________________ and the result is called ___________________.

every available niche tends to be filled; resources are fully exploited; lacks open niches or unexploited resources; exclusion

Loams are usually __________________________________.

excellent soils for crop production

Economists call costs and benefits that are not included in the price __________.

externalities

Parasites that can grow outside the plant are called _______________.

facultative

Accelerated erosion removes soil _____________________________________, reducing the depth of the _________________________________.

faster than the new soil can be formed; productive soil

Enough food is produced to _________________________________. However, __________________________________ exist in both developed and undeveloped countries.

feed the world's population; malnutrition and starvation

Only about 2.5 percent of cropland is devoted to ____________________, both in the United States and worldwide.

fiber crops

The quality of forage is affected primarily by the amount of __________ it contains and its __________.

fiber; digestibility

Surface fibers are those in which the __________ are produced on the __________ of the plant in association with __________. Examples: __________

fibers; surface, floral structures; cotton and kapok

Each stamen consists of a ___________; The _______ produces the pollen; the __________________ supports the anther.

filament and an anther; anther; stamen?????

Most annual and biennial plants ___________________.

flower and fruit only once before dying

Numerous aspects of plant growth and development are controlled by photoperiod including ______________________.

flowering

This shift in food consumption patterns coupled with the tremendous increase in world population, especially in developing regions, requires continuing increases in the world's ___________________________.

food producing capability

Plant scientists have to find ways to meet our need for _____________________ ________________ from plants without ________________________________.

food, fuel, and other products and services; negatively affecting the environment

Humans depend on field crops for much of their __________, and for many other industrial uses.

food, grains for animal feed, clothing, rope, biofuels

Vernalizing bulbs in coolers then bringing them into the greenhouse where the warm temperatures cause the plants to grow and flower is called ____________.

forcing

Most of our energy consumption is based on ________________, and a footprint is associated with _________________________________________________.

fossil fuels; extraction, processing, and distribution of theses fuels

Growth can be measured as increases in ___________________________________.

fresh or dry weight, volume, length, height, or surface area

A far greater footprint arises _________________________________________ ________________________________________________________________.

from the carbon produced as the fuel is burned to generate energy

If a plant is self-fertile, it produces _______________.

fruit and seed with its own pollen, without the transfer of pollen from another plant

After fertilization, portions of the flower develop into a _____________, which bears ____________.

fruit; the seeds

The most expensive and most reliable establishment option of forage crops is __________. It involves destruction of the __________ by mechanical or chemical means, a mechanical operation to __________, mechanical treatment of the soil to establish a __________.

full cultivation; existing vegetation; bury this vegetation; establish a fine and firm seedbed

It is important for spring planting that the soil should be _____________________________________.

fully charged with water, but waterlogged conditions are harmful for most crops

The roots of nearly all plants in the wild are associated with mycorrhiza which are ___________________________.

fungi that assist in plant uptake of nutrients and water

A __________ is one that is derived through the use of molecular biology techniques.

genetically modified organism (GMO)

A side effect of the _____________________ of trade is that _______________ are spread around the world more easily. A recent example is the introduction of the _________________________ into the _____________________ from wooden pallets, carrying goods from __________ to the port of Detroit.

globalization; pests and diseases; Emerald Ash Borer; Great Lakes region; China

After the forest is cleared, ___________________________________________ ________________________________________________________________.

good crops can be raised for a year or two, but the nutrients are soon exhausted

Herbicides are often broadly classified as __________.

grass killers, broad-leaf killers, or nonselective (kills both grass and broad-leaves)

The area between the deserts and the forests consists of __________________ ____________________________________.

grassland and savanna

Conserved forages also provide a useful function by providing forage during periods when __________.

grasslands might be dormant or not growing rapidly enough to support livestock needs

The larger leaves allow for a ________________________________________________.

greater area to absorb light

Perennial plants have two strategies for winter survival: dying down to ______________ but survive as ______________________________________ or their stems become _______________ and acquire __________________________.

ground level; underground storage structures with buds, from which new growth begins each year; dormant; a degree of cold hardiness that varies with plant species

Economic losses resulting from sudden outbreaks of pest activity can be prevented if __________.

growers are aware of the biology of the various crop pests, monitor fluctuations in pest population activity, and implement timely corrective action

Our major food fiber wood and ornamental plants belong to two main classes - the ____________________, represented mainly by the ___________________ ________________; and the ____________________, usually _____________ ____________________________.

gymnosperms; narrow-leaved evergreen trees; angiosperms; broad- leaved flowering plants

Collectively the carpels are known as the ____________________.

gynoecium

During reproduction the new cell receives ______________________________________, resulting in genetic segregation.

half of it's chromosomes from the male parent and half from the female parent

To overcome excessive fruit set, __________, either by hand thinning, machine shaking, or chemical sprays.

half or more of the fruits are removed at a very early stage

Areas of human settlement tend to be _________________________________.

heat islands, with higher temperatures than the surrounding countryside

Annuals, which are _______________ complete their life cycle (seed to seed) in ___________________.

herbaceous (non-woody); one growing season

Perennials are either _________________.

herbaceous (non_woody) or woody

A __________ is applied to remove all existing weeds in the field thus preparing for a clean seedbed for planting.

herbicide

Crop ecosystems are usually more vulnerable to _____________ because the number of _______________________________________________________.

herbivory; predators is low or nonexistent

From the earliest history of modern humans, the shaman and wise elders of a tribe used _______________________________________________________.

herbs to treat diseases and disorders among tribal members

Most plants do not grow well in _______________________________________.

highly acid or highly alkaline soils

The scar that remains after breaking the seed from the stalk is called the ____________, and the small opening near the hilum is the _____________.

hilum; micropyle

A ____________ is a distinct layer of soil having _________________________ differences resulting from soil-forming processes as seen in a vertical cross-section.

horizon; physical and/or chemical

The productivity of ecosystems is an indication of ________________________ ________________________________________________________________________________________________________________________________.

how much we can expect to harvests from them without causing lass of species or collapse of the whole ecosystem

Groundwater and the surface fresh-water supply are replenished through the ____________________, which is driven by the input of ___________________, both directly as _______________ that promotes _____________________ and indirectly through air currents that move ________________________________.

hydrologic cycle; solar energy; radiant heat; evaporation of water; water vapor from one area to another

The designation as a long- or short-day plant is not based on the absolute length of day, but rather _________________.

if the photoperiodically controlled process is induces only at daylengths longer or shorter than specific daylength (called the critical daylength)

Plant scientists studied ways to improve crop productivity __________________.

in a cost effective way

Plants can draw on a fraction of the water ____________________, but much of it is _________________________________________.

in the ground; below the depth of root penetration

When a plant's own pollen will not grow through the style into its embryo sac, this is called _______________.

incompatibility

Increases in plant population may __________, thereby increasing the risk of __________.

increase plant height and reduce stem and stalk strength; lodging

Two major trends that will affect crop production and the global environment are the _____________________________________________________________.

increases in human population and energy use

As the sun rises the angle of incidence _______________, light intensity _______________, so does _________________________ until the photosynthetic machinery is _______________. Then photosynthetic activity gradually ________________________________________________________.

increases; increases; photosynthetic activity; saturated; declines as the day progresses toward sunset

In wood perennial plants, both the shoot and the root system remain __________________, each growing to the ultimate size for the particular plant as programmed by _________________.

indefinitely; its gene complement and the environment in which it is growing

Vernalization is any cold temperature treatment that ____________________.

induces or promotes flowering

In most if not all developed countries, farmland is being lost forever to ________ ________________________________________________________________.

industrial, residential, or recreational development

The yields we achieve in ______________ countries need to be achieved worldwide. These yields in turn require that ___________ at least of _________ _____________________________, have to rise in other countries to match those in ___________________________.

industrial; inputs; fuel, fertilizer, and probably pesticides; North America and Europe

Parasitoids can be helpful in crop ecosystems when they __________________ ________________________________________________________________.

infect herbivorous insects such as caterpillars

When rain hits the ground, it can penetrate pores in the soil through the process of _______________ or it can _______________.

infiltration; run off

Carbon dioxide absorbs ____________________ from the earth so that ____________________________________. This phenomenon is loosely referred to as __________________________.

infrared radiation; heat is retained in the atmosphere; the greenhouse effect

__________ is loss of plant vigor resulting from an instantaneous event such as lightning strike, hail damage, chemical burn or mechanical damage.

injury

Pollen transfer from the anthers to the stigmas is principally by ______________.

insects and wind

__________ relies on the use of several methods rather than one single means for developing an effective and sustainable pest management program.

integrated plant health managements (IPHM)

The spongy mesophyll parenchyma contains the __________________.

intercellular spaces through which carbon dioxide, oxygen, and water pass

The chloroplasts contain pigments capable of _________________________________________________ necessary to drive the photosynthetic processes.

intercepting light and converting electromagnetic energy into the chemical energy

The term __________ is used to classify species that are particularly aggressive, regardless of their life cycle.

invasive weed species

In dry fruits (papery or stony), the entire pericarp ___________________.

is dry at maturity

Plant development is _______________________________________________.

its progress through its life cycle

These enterprises provide __________________________________________ ____________________________________________________.

jobs for many people, from day laborers to corporate executives

Rotating a nitrogen-fixing legume crop with a nonlegume on a regular basis is a common farming practice to _________________________________________.

keep nitrogen levels up in a field

Ornamental crops are much more ____________________________________, accounting for nearly _______________________________________________.

labor intensive than other crops; 20 percent of U.S agricultural labor costs

New homes are an expanding market for _______________________________.

landscape supplies and services

The pericycle is a meristematic region producing ________________________________.

lateral (branch) roots that grow outwardly through the cortex and epidermis

The _________________________ which produce secondary growth, are cylinders of _____________________________ starting somewhat below the apical or subapical meristems and continuing through the plant axis.

lateral meristems; actively dividing cells

Temperature is primarily influenced by _________________________________ ________________________________________________________________.

latitude, and within latitudes, it is influenced by the height of the land above sea level

Transpiration helps regulate _______________________ and provides the force that _____________________________________________________.

leaf temperature; draws water into and through the xylem

By observing the full range of interactions and processes in natural ecosystems, we can __________________________________________________________ _____________________________.

learn how to manage crop ecosystems to achieve the goal of sustainability

The ______________________________________________ manufacture food, which is transported to the roots, flowers, and fruits through the _____________.

leaves and herbaceous green stems, phloem

The __________________________ includes many important crops such as ________________________________________________________________.

legume family; beans, peas, and alfalfa

It also affects the amount of ______________ and available for absorption by _________________.

light entering the leaf; chlorophyll

They studied _____________________________________ and developed ways of managing or monitoring those factors to ______________________________.

light, soil, water, and temperature; influence or predict plant growth

Plants require _____________________________________________ and many may require _________________________________________________.

light, water, and nutrients for growth; pollinators and dispersal agents for reproduction

At low light levels, temperature ________________ on the rate of photosynthesis because light is the _____________________.

little effect, limiting factor

A fraction of the number of the particulates consists of ____________________________________.

living organisms, plant pollen, microbial spores, and insect eggs

Plants also encourage infiltration when they die by creating a layer of _________________________ that tends to form on bare soil.

loose, absorbent, organic debris at the soil surface rather than the smooth, nonabsorbent, caked surface

Soil with a high percentage of sand ______________.

loses water quickly, retaining little for plant use

Light that is reflected from the surface of a leaf is _________________.

lost for photosynthesis

Under conditions of __________________________________________________________ plants often lose water through transpiration faster than their roots can absorb it. This causes the __________________ to close and the leaves to _____________________________.

low soil moisture (drought) and hot, drying winds, stomates, wilt temporarily

Heliotropic movements are also used to ______________________.

lower the amount of light absorbed by reducing the angle of incidence of sunlight on the leaf when overheating might occur

Coniferous trees are a valuable crop for ________________________________.

lumber and paper making

Surviving farms can ___________ directly to the surrounding population.

market

The most important objective in grazing is to __________.

match the supply of forage production to the nutritional requirements of livestock

A fruit is a _______________; it is generally a _________________, but there are ________________ fruits that are seedless.

matured ovary plus associated parts; seed-bearing organ; parthenocarpic

The organelles of the plant cell are contained within a ________________________________________, which in turn is encased within a _________________.

membrane-bound protoplast; cell wall

Companion cells aid in _______________________________ and are closely associated with sieve-tube members.

metabolite conduction

US plant hardiness zones are defined according to the ___________________.

minimum temperatures that can be expected

The term often used when discussing the action of herbicides on biochemical processes is __________.

mode of action

Angiosperms are divided into two subclasses: the ________________________ or _________________, which have an embryo with ____________________, and the ____________________ or ______________, which have an embryo with ______________________________.

monocotyledons; monocots; one cotyledon; dicotyledons; dicots; two cotyledons

Competition occurs when ____________________________________________ ________________________________________________________________.

more than one organism draws on a resource that is in short supply

When fires sweep through grassland, ______________________________, but grasses and herbaceous perennials, __________________________________ ________________________________________________________________.

most trees are killed; which have their growing points at or below the soil surface, typically survive

Heat transfer by convection (_____________________________) is an important factor in both ____________________________________.

movement by a carrier; weather and climate

In soils largely composed of very fine clay particles, _______________________ ________________________________________________________________.

movement of both air and water can be limited

Each thin-walled endodermal cell is completely encircled by a __________________________.

narrow, thickened band of waterproofed material known as the Casparian strip

Because the crops used are often food crops, using them for fuel ____________ ______________________________________________. Even if they are not food crops, they may _______________________________________________.

negatively affects the food supply for humans and domesticated animals; occupy land that was formerly used for food crops

Simple, microscopic, multicellular animals typically containing 1,000 cells or less are __________.

nematodes

Soil animals include _______________________________________________ ________________________________________________________________.

nematodes, mollusks (slugs and snails), annelids (including earthworms), and arthropods (mites, insects, millipedes, spiders, etc.)

Other classes of parasites include _______________ and some ____________ ______________, particularly those that form ___________________________.

nematodes; insects and mites; galls on leaves and stems

A plant's survival depends on temperatures _____________________________.

never falling below the minimum that it can tolerate

Forage crops and rangelands have __________ to humans in terms of __________.

no immediate value; direct food products

Even though cytokinins are strongly involved in plant growth regulation, _____________.

no important agricultural uses have been developed for them

Without fertilization, _____________; therefore, parthenocarpic fruits are ____________.

no seeds are produced; seedless

The cell wall is ________, made up of _________________________________.

nonliving; cellulose, pectic substances, and lignins

Because of high rates of growth, ______________________________________ ____________________________________________ so rainforest soils contain little in the way of free nutrients.

nutrients are rapidly taken up by plants and rapidly recycled from dead organisms

The leaves contain on a fraction of the _________________________________ _________________________________, and trees manage to withdraw much of the __________________________________ from their leaves before they are shed. So forest soils ______________________________ and tend to have only ____________________________________________________________.

nutrients locked up in the permanent structure of the tree; nitrogen and phosphorus; develop slowly; a thin organic-rich layer

Ecological research is ______________________________________________ ________________________________________________________________.

often descriptive of a situation within an area that represents the larger ecosystem

Apart from fiber and biofuel, the major nonfood use of crops is for ___________ ___________________________________.

oil-based industrial products

Incomplete flowers lack _____________.

one or more of the four parts: - Sepals - Petals - Stamens - Pistil

The guard cells, which occur in pairs on both sides of the stomata, control the ___________________________________ through which carbon dioxide ________________________, and oxygen ________________.

opening and closing of the stomata; one of the raw materials for photosynthesis; a product of photosynthesis, is released

Anywhere _______________ exist is, in a strict sense, _______________.

organisms; an ecosystem

Oxidation reactions form ____________________________________________.

oxides of parent material by reaction with oxygen

After the __________ in the mass of tightly packed chopped material is used up by plant respiration, __________ and act on the carbohydrates in the plant tissue to form __________, which essentially __________ the plant material.

oxygen; anaerobic bacteria multiply; lactic acid; ferments

The _______________ is an indeterminate branching raceme.

panicle

Soils are produced from ____________________________________________ __________________________________________.

parent material, such as rock, by the interaction of climate and organisms

Most farms are run as _____________________.

part-time businesses

A __________ is a disease causing organism.

pathogen

Fiber in forage can be present as __________.

pectin and hemicellulose, cellulose, and lignin

Most forage and rangeland species are __________ and part of __________.

perennial plants; year-round production systems

Sepals and petals collectively are called the _______________.

perianth

The ovary wall, which is called the _______________, can develop into ______________.

pericarp; different structures

In the tundra, the ground is __________________________________________ ___________________________________.

permanently frozen except for a surface layer throughout the year

The "particles" also move around the world causing ___________________________.

pest and disease outbreaks on plants as well as allergic reactions in humans

A pesticide has one or more ways in which it can get into an insect or mite. These are known as the __________.

pesticide modes of entry?????

The ________ are the next whorl of floral leaves __________.

petals; inward from the sepals

Unlike xylem, which is mostly made up of hollow tubes created from dead cells, ____________________________________________.

phloem is made up of living cells

Both photoperiodism and shade avoidance are examples of ________________ which means _____________________________________________.

photomorphogenesis; plant shape is determined by light quality

The primary function of leaves is _________________________; the secondary function is _________________________.

photosynthesis; transpiration

Some roots act as storage organs for __________________________________.

photosynthesized food

Phototropin is responsible for ________________________ which is movement ______________________________.

phototropism; in response to light

A compound leaf resembling a feather is termed _______________; one resembling the palm of a hand is _______________.

pinnate; palmate

Succession begins with ______________________________ that can survive under special conditions.

pioneer species

The carpel, also called the ______ is the ______ component of the flower.

pistil; central female

The channels around plasmodesmata are called ________.

pits

Increasing the use and efficiency of ________________________ and ________ _______________ would be a way to utilize photosynthetically captured energy.

plant biomass; bio-based fuel

Plant growth regulators include ____________________—_____________________—as well as other chemicals not found naturally in plants but that when applied to plants, influence their growth and development.

plant hormones- natural and synthetic

Hay quality is determined by __________.

plant maturity, leafiness, color, odor, and amount of foreign material

Adventitious roots can arise from ________________________.

plant parts other than stems, such as from leaf petioles or leaf blades or even from old root pieces

The study of plant disease is termed __________

plant pathology

The seeding rate of a crop is determined by __________.

plant population (or plant density) required to optimize yields in a particular environment

We have learned the hard way that ______________________________ and what we do to help in one aspect of plant growth _________________________ _______________________.

plants do not grow in isolation; may have detrimental consequences elsewhere

The plasma membrane, also called the ________________________________, is a ____________________________________ surrounding the cytoplasm.

plasmalemma; lipid bilayer

Individual cells in a tissue are connected to one another via strands of cytoplasmic material, called ______________________________, which extend through _________________________________.

plasmodesmata; the plasma membrane

A multitude of other uses include the manufacture of __________.

plastics, paint, varnishes, lacquers, soaps, detergents, inks, cosmetics, lubricants, medicines, fabric, and paper

Fruits develop after _________________.

pollination and fertilization

The oil seed meal from crops ________________________ and the __________ _________ from ethanol production can be used as ____________________.

processed for biodiesel; fermentation residue; animal feed

It is not known if organic farming has the capability to ______________________ _________________________________.

produce the quantities of crop products needed in today's world

In herbaceous monocotyledonous plants stem growth originates from an apical meristem that ______________________________.

produces vascular bundles scattered throughout the parenchyma

The _______________ of farming has been helped to some extent by ____________ the uses of staple crops (e.g., _________ and _________ made from corn and _______ from soybeans) and by adopting ______________ crops.

profitability; diversifying; ethanol; syrup; tofu; alternative

The production of adventitious roots is the basis for _______________________.

propagation by stem cuttings

The amount of infiltration and runoff is determined by ________________________.

properties of the soil surface, amount of slope, and the degree of saturation of the soil with water

The ____________ is a single elongated indeterminate arrangement of stalked flowers.

raceme

Germination begins with the emergence of the _______________ or the primary __________ and the ____________ or the primary __________.

radicle; root; plumule; shoot

The ridge on the seed is the ______________.

raphe

Anyone who works with growing plants for a living has to be able to __________ ________________________________________________________________.

read and interpret the scientific and trade literature of his or her discipline

When these pigments are irradiated with light containing all the visible wavelengths, they absorb mostly from the _____________________________ of the spectrum and reflect or transmit much of the ______________________________________________________________________________.

red and blue portions, green portion which is why leaves are seen as being green

Plants compete for light by ________________.

redirecting growth and development so they they produce leaves that are above the leaves of their neighbors

Improvements in production were developed not only to ____________________ _____________________________________, but also to allow farmers to be ___________________________________________.

reduce labor and increase productivity and profit; better stewards of the environment

Dust and other pollutants generated by human activity ____________________ __________________________________.

reduce light intensity and can increase rainfall

Some plants can compensate for the __________________ at low solar angles through _______________________, in which leaf angles are _______________ so that the sun's rays are normal, or ____________________, to the leaf during most of the day.

reduced light intensity and increased reflection; heliotropic movements; adjusted; perpendicular

Successful water management involves ________________________________ ________________________________________________________________.

regulating the availability of water to meet evaporative demand

The nonliving organic components of the soil are _________________________.

residues of plants and animals

A __________ is an underground stem that grows __________________. Examples: ____________________________

rhizome; horizontally; bananas, cannas, certain irises, certain bamboos, and some grasses (quack grass, Johnson grass, and Bermuda grass)

Soil is derived from ________________________________________________.

rocks, minerals, and decaying organic matter

Because most of the water and nutrients a plant requires enter through the __________, a healthy actively growing ______________ that is constantly producing root hairs is necessary _____________________________________________.

root hairs; root system; for good plant growth and development

In herbaceous perennials, the _________________ can remain alive ________________ but the shoot system may be killed by ____________________.

roots and shoots; indefinitely; frosts in cold winter regions or by senescence-inducing factors

Hard fibers are those that are __________. Example: __________

rougher, more lignified strands of veinlike bundles of phloem and xylem supporting cells primarily from leaves of monocotyledons

The _________________________ was a very distinct line of demarcation with a defense wall separating urban from rural areas.

rural/urban interface

Large areas of land have been damaged by __________________ as a result of _______________ in many parts of the world.

salinization; irrigation

Irrigation water adds small amounts of various ________ to the soil. If these salts are not washed away by _________, they can build up to concentrations that ______________________.

salts; sufficient volume of irrigation water or natural rainfall; inhibit root growth

The main stem and its branches are the ______________________________________.

scaffold of the plant, supporting the leaves, flowers, and fruits

A ____________ is a mature ovule.

seed

The __________ serves as the primary source of seed for annual weed infestations in crop fields.

seed bank

Stages of development include _______________________________________ _____________________

seed germination, growth of vegetative organs and tissues, initiation and maturation of reproductive organs and tissues, fertilization, seed development and maturation, and senescence and death

The fruit protects the ________ in some plants and helps ____________.

seed; disseminate it

An alternative to irrigation is to _______________________________________.

select a crop that has a low water demand

The control of development through ________________ is mediated mostly but not entirely through the action of ________________.

selective gene activation; transcription factors that turn on and off genes

Flowers are _______________ by wind or insects.

self-pollinated or cross-pollinated

If it is ______________, it cannot set fruit and seed with its own pollen, but instead requires pollen from _____________, usually of a different clone.

self-sterile; another plant

The _______________ are the leaf like scales that encircle the other __________________, as in the _________________.

sepals; flower parts; carnation and rose

The vascular bundles of an herbaceous dicot usually remain ______________.

separated and distinct, they are arranges in a single circle in the stem

Leaf blades that are attached directly to the stem and lack a petiole or stipules are called _______________________.

sessile leaves

Flowers and inflorescences vary in _________________, a fact that aids in identifying a plant's _________________.

shape and form among the species; species, genus. and family

We often think of an environment as a limited area in which the individuals _____ ______________________________________________.

share the available resources

Hay is defined as the __________ and in some cases, the flowers, fruits, and seeds, of forage plants that are preserved by __________.

shoots and leaves; field drying, harvested, and stored for future feeding to livestock

The term __________ is used when the pathogen or part of the pathogen is observed in or on the affected plant.

sign

The two terms often used when discussing plant disease and injury are __________. .

sign and symptom

The root system is a _______________________________________________, about one-quarter to one-third of the total, depending on the ________________ ____________________________________________.

significant portion of the entire dry weight of any plant; storage or fibrous nature of the root

Leaves are usually classified as simple, having a _____________ or compound, __________.

single leaf; having three or more leaves

The tropical forests are a major _______ or depository, for the carbon dioxide that we generate through our ___________________________________. Losing that depository contributes to increasing atmospheric _____ and _______ _________________.

sink; fossil fuel consumption; CO2; global warming

Factors affecting seeding depth include __________.

size, type of emergence, soil and seedbed conditions, date of planting, and available moisture supply

Because the conifers are mostly ______________________________________ ________________________________________________________________.

slow-growing evergreens, recycling and the availability of nutrients is lower than in the deciduous forest

The loss of the _________________________ and the increase of the ________ _________________ have become a serious _________ and _________ issue.

small family farm; corporate mega-farm; social; political

A key component in the relationship between climate and vegetation is _______.

soil

Soil cultivation and major construction projects cause _____________________.

soil particles to be released into the atmosphere

In temperate regions, the major environmental factors determining planting date are __________.

soil temperatures and moisture

Leaves may be _______________ or sunburned when exposed to __________________.

solarized; high light intensities

Flowers borne singly on a stalk are called _____________.

solitary

Oil from _______________ and other oil crops such as ____________________ is extracted and processed to be used as ____________________.

soybeans; sunflower and canola; biodiesel fuel

A __________ is a complete densely flowered structure surrounded by a spathe.

spadix

The _______________ is an elongated, simple, indeterminate inflorescence with _________________.

spike; sessile (no stalk) flowers

Certain fruit trees bear flowers and fruits each spring on persistent shortened stems called ________. Examples: ___________________________________

spurs; apples, cherries, plums, pears, bear flowers, etc.

The male part of the flower is the _______________.

stamen

The _________________________ in corn and switchgrass are ____________ _________________________________________.

starches and sugars; fermented to produce ethanol

The pericycle and the vascular cylinder are collectively called the ____________.

stele

The epidermal layer contains opening or pores called ________________, each surrounded by two _____________________.

stomates; guard cells

Physical weathering is also caused by moving water, as in _________________ ________________________________________________________________.

stream erosion, sheet erosion, roll erosion, or wave action

The _______________________________ produces new cells in the region a few micrometers behind an active shoot or apical meristem.

subapical meristem

Many people have criticized the aspects of ____________________, but it leads to new opportunities.

suburban sprawl

The change in plant communities over time is known as ___________________.

succession

Although ________________________ are vital for plant life, _______________ may be the most important factor in the decision about whether _____________.

sunlight and water; temperature; a crop can be grown or when to plant a crop in a given location

According to classical economics, the price of commodities results from the balance between the __________ of commodities and the __________ for them.

supply; demand

Vegetation aids soil formation by _____________________________________ ________________________________________________________________.

supplying organic matter in the form of dying and decomposing plants

The idea of _______________ as a guiding principle in crop production is an attempt to transcend the mind-set of high yields this year being more important than low yields in future years because of soil degradation.

sustainability

A relationship between two dissimilar organisms living together for mutual benefit is called ____________________.

symbiosis

__________ are visual or otherwise detectable reactions or alterations of a plant as a result of disease or injury.

symptom

Organic producers grow crops without the use of __________. .

synthetic herbicides and fertilizers

Some plants have a dominant ______________, which ___________________, together with limited lateral root growth. Examples: ______________________________________________________

tap root; develops downward; carrots, beets, and turnips (all well known root crops)

The annual leaf fall adds a certain amount of nutrients to the litter layer of the ________________________________________________________________.

temperate deciduous forest

Urban development has a major effect on the __________________ at all times of the year.

temperature

The most important climatic variables are ______________________________ ________________________________________________________________.

temperature, rainfall (more correctly, precipitation), and any seasonal variation in both

A defining feature of the climate of the temperate zone is that _______________ ______________________________________.

temperatures are not conductive to plant growth throughout the year

Some plants of tropical origin may be injured at _______________. This is referred to as ________________.

temperatures well above the freezing point; a chilling injury

The distribution of different particle sizes determines ______________________ ________________________________________________________________.

the ability of soils to hold and transmit water

We can reduce our human footprint by reducing _________________________ _______________________________________________.

the area or the intensity of our activities

The best test to distinguish between simple and compound leaves is to examine ______________. A true leaf ___________; a leaflet ___________.

the base of the petiole; has a bud in this location; does not

The plant cell is __________________________.

the basic structural and physiological unit of plants

Both gymnosperms and woody perennial angiosperms grow in girth each year when __________________________.

the cells of the vascular cambium divide, forming annual rings of xylem

Many seeds can be planted only after _________________________________, and spring-flowering perennials can be ________________________________.

the danger of frost has passed; injured by late frosts

net photosynthesis is the term for _________________________________________________________________________________________________.

the gain in carbohydrates from photosynthesis after carbohydrate loss through respiration is deducted.

The juvenile phase is characterized by _____________________.

the inability to reproduce sexually

The further from the climax community we try to stay, _____________________ ________________________________________________________________.

the more work and inputs are required to maintain the ecosystem

Controlled experiments are __________________________________________ ________________________________________________________________.

the most certain way of obtaining reliable information on which to base decisions

The organisms in an ecosystem interact according to ______________________ ________________________________________________________________.

the nature of the species and their role in the ecosystem

The key to a meaningful controlled experiment is to be sure that _____________ ________________________________________________________________.

the only factor affecting the outcome is the factor you set out to study

In the warmer tropical and subtropical climates, the planting dates are often determined by __________.

the onset of rains

One of the most important aspects of growing field crops is __________.

the order in chich crops follow one another (sequence) either during the same growing season or through consecutive seasons

Many of the most important organisms and ecological processes in all ecosystems are invisible to us because _________________________________ _____________________________________________________.

the organisms are small or because they and the processes occur in the soil

The data must be analyzed statistically to see if __________________________ __________________________________________.

the original hypothesis is supported or not

Although the winds move air masses between different latitudes, ____________ _______________________________ via the Coriolis effect.

the rotation of the earth gives them easterly or westerly shift

When the desert is irrigated, _________________________________________ ________________________________________________________________.

the salts are left behind after the water evaporates from the soil or through plant transpiration

Desert soils are difficult to manage in the long term because _______________ ________________________________________________________________.

the salts tend to accumulate to levels that inhibit the growth of plants

Parthenocarpy is the formation of fruit without _______________.

the stimulation of pollination and fertilization

Parasites differ from herbivores because _______________________________ ________________________________________________________________.

they cause a disease rather than simply eating their way through the tissue

For species to coexist in an ecosystem, ________________________________.

they must occupy different niches

Bodies of water affect air circulation because ________________________. This leads to an _____________________ and an __________________ in the evening.

they warm up more slowly than the land does in the daytime and cool more slowly at night; onshore breeze toward the land in the morning; offshore wind

The leaves of some plants, such as cabbage have a _____________, called the ____________.

thick waxy surface; cuticle, that greatly reduces water loss

The root cap is a ________________________________.

thimble-shaped group of cells that protect the actively dividing meristem as it penetrates the soil

Generally, the leaves of a given plant species grow ________________________ in areas under low light intensity than under high light intensity.

thinner and longer

Leaves grow ___________________ and ____________________ in area under low light intensity than under high light intensity.

thinner; longer

The level of infestation or infection below which the economic value of a plant or crop is not comprised is referred to as the __________.

threshold level

The basic component of a grass is the __________---and a grass clump is __________.

tiller; a collection of tillers

By planting deep and having adventitious roots form, the young plant is much less likely ________________________________________________________.

to be damaged by wind or rain

The ability of a plant to maintain its yield in spite of heavy disease or plant pressure is known as __________.

tolerance

The membrane surrounding the vacuole is called the ___________, and it serves an important role by __________________________________________________.

tonoplast; controlling the flow of water and dissolved materials into and out of the vacuole, maintaining cell turgor, and other functions

By cultivating plants, humans reduced the need to ________________________ ____________________________________.

travel to follow the food supply

Smaller-scale irrigation of horticultural crops, including ornamentals, often aims to supply the water more directly to the plant roots through ________________.

trickle-feed pipes or spray emitters close to the soil surface

Plant cultivation is believed to have started in _______________ and _______________ regions in the Middle East and Africa.

tropical; subtropical

The United States has about _______________________________ as China but ____________________________.

twice as much cropland; one-fifth of the population

Double cropping involves the production of __________.

two crops, one following another, during one growing season

Biennials, which are herbaceous plants, require ______________ to complete their life cycle (seed to seed).

two growing seasons (not necessarily two years)

Golf alone is now equivalent to about _____________ of major crop sales and involves ____________ of the US population.

two-thirds; 12%

The _______________ is an indeterminate, often flat-topped, cluster of flowers that are of equal length and arise from a common point.

umbel

Once a disease has been identified, its prevention and/or control depends on __________.

understanding its cause, the factors that favor the disease, which plant parts are affected, and when the disease organisms are spread

The __________________ is composed of the plants that grow under the canopy of other taller plants.

understory

The ovary contains ______________ that are attached to a ____________; the ovules develop into _____________.

undeveloped ovules; placenta; seeds after pollination and fertilization

A bud can be defined as an _____________________, largely composed of meristematic tissue, and generally protected by ______________.

undeveloped shoot or flower; modified leaf scales

A dome of warm air exists over cities, forming the so-called ________________ ___________________________________.

urban heat island or dome

If the RH is less than 100%, the difference between the actual vapor pressure and the SVP is known as the_________________________________________.

vapor pressure deficit (VPD)

Photoperiodism is the photomorphogenic response to _________________.

variations in day length

Organisms that carry or transport disease are called __________.

vectors

Air movement tends to be slowed down by ______________. This effect is most noticeable under a continuous _______________________________________.

vegetation; canopy of herbaceous or woody vegetation

Plant parasites include many kinds of __________________________________.

viruses, bacteria, and fungi

All ____________ are obligate parasites, whereas ________________________ may be obligate parasites or facultative.

viruses; fungi and bacteria

Vacuoles serve as a storage reserve for _____________________________________.

water and salts, as well as toxic products

Large areas are often irrigated with _____________________ to some form of ______________________________. This method can result in losses because the water may _________________.

water piped under pressure; overhead irrigation; fall outside the crop area and a proportion evaporates before it reaches the root zone

Dissolution is the process by which the constituents of parent material dissolve in ________________________________________________________________.

water, or weak, naturally occurring acids and are leached away

The outside surface of epidermal cells is usually covered with a ____________________________, which reduces _______________________.

waxy surface called cutin; water loss

Although the hose may not die, it is usually _____________________________ ________________________________________________________________.

weakened, making it vulnerable to attacks by other (secondary) organisms

Soils differ around the world, but they are basically composed of _____________ ________________________________________________________________.

weathered rock, air, water, decomposed organic material, and various organisms, all working together in a complex system capable of supporting the growth of land plants

Any plant out of place, growing where it is not wanted, that interferes with human activities or competes with a desired plant for water, nutrients or sunlight is a __________.

weed

We call the other plants __________, and their presence is ________________ ________________________________________________________________.

weeds; a problem to the extent that their resource requirements overlap those of the crop species

Without cultivation __________ would move in, followed by a thicket of _______ _________, and the process would culminate in a ________________________ _______________________________________.

weeds; woody plants; forest of the longer-lived tree species

All of the kinds of ecosystems that made up the biomes contained ___________ _______________________ which were often __________________________ ________________________________________________________________.

wet areas or wetlands; the most productive areas because water was permanently available

A leaf scar, _____________, is visible just below each _________.

where the leaf petiole was attached; bud

The balance between evapotranspiration and precipitation defines __________________________________.

whether the climate is moist or dry and whether irrigation is likely to be necessary to produce crops

A __________ is an underground stem whose terminal portion swells as it accumulates _______________________.

white (Irish) potato plant; starches and sugars from photosynthesis in the leaves

In contrast to many other countries, the United States has seen an overall increase in the area of _______________.

woodland

Many kinds of plants are cultivated for their fibers which are used to make __________, and hundreds of other products.

yarn, fabrics, rope, paper, insulation, raw cellulose

One of the newest plants to be recognized for its medicinal benefits is a _______ ______________________________________, a chemical shows promise in the treatment of ______________.

yew (Taxus) that produced taxol; cancer

Soils without well-developed horizons are classified as ________________, even though the parent material __________________________________________.

young soils; over long periods of time differentiate the soil into horizons