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Glossary Acids and Bases

p

public order

A primary public good is the maintenance of public order by governments, which are formed to protect the life and property of their citizens. Without government, people suffer lawlessness and chaos.

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  diameter

Diameter is the distance between two points on a circle, measured through the center.

exterior angle

An exterior angle is an angle outside a polygon that lies between one side and an adjacent extended side.

2

2D gel electrophoresis

A technique for separating proteins to further identify and characterize them. Proteins are separated in the first dimension based on their isoelectric point, and then in the second dimension by molecular weight.

Read more about this term in the Online Textbook:
Proteins and Proteomics: 2D Gel Electrophoresis to Identify Cellular Proteins
Related Terms:
Isoelectric point
Polyacrylamide gel electrophoresis (PAGE)
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View Terms by Unit: Proteins and Proteomics

3

3 Points

The scoring guide should be broad enough to allow for differentiated results, but narrow enough to make it easy to write discrete and measurable performance statements.

5

5 Points

The scoring guide should be broad enough to allow for differentiated results, but narrow enough to make it easy to write discrete and measurable performance statements.

r

reference dose

The U. S. Environmental Protection Agency’s maximum acceptable oral dose (abbreviated RfD) of a toxic substance, most commonly determined for pesticides.

a

A-B-A Design

[Design]
A research design in which participants first experience the baseline condition (A), then experience the experimental treatment (B), and then return to the baseline (A).

abolition

The movement to end slavery in the United States. While calls for abolition emerged from Quaker activists like John Woolman during the early eighteenth century and from proponents of natural rights during the American Revolution, abolitionism did not become an important political force in America until the early- to mid-nineteenth century.

absolute comparison

An absolute comparison is an additive comparison between quantities. In an absolute comparison, 7 out of 10 is considered to be larger than 4 out of 5, since 7 is larger than 4.

abstract

A summary of a research report, typically in the range of 40 to 250 words. It is meant to capture the essential information found in the research report, so it generally has sentences devoted to introduction, methods, results, and conclusions. Abstracts contain important key words used for searching through the scientific literature. Review articles, oral and poster presentations at scientific meetings, and grant applications will also often have abstracts.

accommodative monetary policy

A central bank policy designed to stimulate economic growth by lowering short-term interest rates, making money less expensive to borrow.

Acculturation

The process of acquiring or adapting to a new culture, its traditions, customs, and patterns of daily living.

accuracy

The accuracy of a measure (an approximate number) refers to the ratio of the size of the maximum possible error to the size of the number. This ratio is called the relative error. We express the accuracy as a percent, by converting the relative error to a decimal and subtracting it from 1 (and writing the resulting decimal as a percent). The smaller the relative error, the more accurate the measure.

accurate

Reliability: The degree to which a test produces similar scores each time it’s used; stability or consistency of the scores produced by an instrument.

 

Validity: The extent to which a test measures what it was intended to measure.

Achilles

The greatest of the Greek warriors at Troy, Achilles deliberately chose a short life and a hero’s death over a long life of average distinction. He meets Odysseus in the underworld, where his existence seems very grim. But Achilles is glad when Odysseus tells him that Achilles’ son has carried on as a hero in battle on earth, leading to his own likely early death.

Acid

A compound that has a proton or protons that can dissociate in water; also, when one molecule has a proton or protons that dissociate more readily than those of another (i.e., it has a higher Ka), the first is said to be the more acidic molecule.

Acid dissociation constant

A form of the equilibrium constant for the dissociation of an acidic molecule into a proton and its conjugate base. It is abbreviated “Ka.” The acid dissociation serves as a measure of how acidic the molecule is; the larger the value of Ka, the more acidic the molecule.

Acid dissociation equation

The chemical equation for the separation of an acidic molecule into a proton and its conjugate base. The general form can be written:

HA + H2O equilibrium arrows H3O+ + A

where HA is the acidic molecule, H3O+ is the stable form of the proton, and A is the conjugate base of the acidic molecule.

acid rain

Rainfall with a greater acidity than normal.

Acidic solutions

Solutions containing a higher concentration of hydronium ion (H3O+) than that found in pure water (i.e., having a pH below 7); also, when one solution has a greater concentration of hydronium than another, it is said to be the more acidic solution.

Acquired Immune Deficiency Syndrome (AIDS)

A severe immunological disorder caused by a virus that destroys the body’s immune system and weakens the ability to fight harmful bacteria.

Action potential

A nerve impulse; a traveling wave of positive voltage that is propagated along a neuron.

Read more about this term in the Online Textbook:
Neurobiology: The Action Potential
Related Terms:
Voltage-gated channels
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Action Potential movement through an axon
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Synapse
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Synaptic Vesicles
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Activated complex

A chemical species midway between reactant molecules and product molecules.

Activation energy

The amount of energy that the reactants need to reach the activated complex.

Activation Synthesis Theory

The idea that during sleep, an automatic activation system in the brain produces a series of random electrical discharges that the sleeper roughly ties together by creating a storyline. An opposing theory to the traditional Freudian idea that dreams are secrets, fears, and the like, rising from the unconscious.

Active site

The specific part of an enzyme that binds the substrate.

Read more about this term in the Online Textbook:
Proteins and Proteomics: Function and Structure Relationships of Proteins
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Virtual Ligand Screening in Drug Design
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Activity series

A list of various chemical species arranged in order of reactivity. It is usually used to describe the ability of various metals to displace hydrogen from water or from acids.

acute angle

An acute angle is an angle with a measurement greater than 0 degrees and less than 90 degrees.

acute triangle

An acute triangle is a triangle with all three angles less than 90°.

Adad

The god of thunder, rain, and floods.

Addiction

The physical and mental state of dependence on a substance or stimulus, to the point where withdrawal symptoms occur whenever the substance is not present in the body.

Addition Rule

If C and D are mutually exclusive events, then P(C or D) = P(C) + P(D).

Adequacy of a Linear Model

A line is adequate to describe the pattern in a set of data points provided the data have linear form. A residual plot is a good way of checking adequacy.

Adharma

Chaos and the disintegration of the order of the universe; adharma is the opposite of dharma. Heroes and warrior-kings of the epic embody dharma (order and sacred duty) while their foes embody adharma (chaos).

adjacent angles

Adjacent angles are angles that share a common vertex and a common side between them.

AdS/CFT

Anti-de Sitter/Conformal Field Theory (AdS/CFT) is a mathematical relationship between two separate descriptions of the same physics. According to AdS/CFT, a string theory in a region of Anti-de Sitter (AdS) space is equivalent to a conformal field theory (CFT) on the boundary of that region. Anti-de Sitter space has negative curvature (a two-dimensional plane is curved in a saddle shape rather than flat), and is one of the simplest geometries in which the equations of general relativity can be solved. A conformal field theory is the type of field theory used in the Standard Model. Although AdS/CFT describes an artificially simple situation—we appear to live in flat space, not Anti-de Sitter space—the mathematical correspondence between the two descriptions of physics has allowed relatively straightforward field theory calculations to shed light on problems associated with the quantum mechanics of black holes. AdS/CFT has also been used the other way, with black hole calculations providing insight into complicated particle collisions and condensed matter systems that are difficult to understand with the conventional field theory approach.

AdS/CFT

Anti-de Sitter/Conformal Field Theory (AdS/CFT) is a mathematical relationship between two separate descriptions of the same physics. According to AdS/CFT, a string theory in a region of Anti-de Sitter (AdS) space is equivalent to a conformal field theory (CFT) on the boundary of that region. Anti-de Sitter space has negative curvature (a two-dimensional plane is curved in a saddle shape rather than flat), and is one of the simplest geometries in which the equations of general relativity can be solved. A conformal field theory is the type of field theory used in the Standard Model. Although AdS/CFT describes an artificially simple situation—we appear to live in flat space, not Anti-de Sitter space—the mathematical correspondence between the two descriptions of physics has allowed relatively straightforward field theory calculations to shed light on problems associated with the quantum mechanics of black holes. AdS/CFT has also been used the other way, with black hole calculations providing insight into complicated particle collisions and condensed matter systems that are difficult to understand with the conventional field theory approach.

adsorption

Process that occurs when a gas or liquid solute accumulates on the surface of a solid or, more rarely, a liquid (adsorbent), forming a molecular or atomic film (the adsorbate). It is different from absorption, in which a substance diffuses into a liquid or solid to form a solution.

Advanced Placement (AP)

Advanced Placement is a program sponsored by the College Board. The AP program gives students the opportunity to take college-level courses in a high school setting; passing the course exam may earn them college credit or advanced standing. AP courses follow guidelines developed and published by the College Board.

aerosols

Liquid or solid particles that are suspended in air or a gas. Also referred to as particulate matter.

Aesthetic Response

An aesthetic response is an affective response or reaction to a text. It reflects the reader’s personal and emotional response based on background knowledge, attitudes, and experiences. Aesthetic responses to a text are student-initiated and will vary from reader to reader. (Adapted from Rosenblatt. The Reader, the Text, and the Poem.)

Affective Disorders

Any disorder in which the primary symptoms are associated with mood disturbances, such as extreme depression, excessive elation, or both.

affective filter

The affective filter hypothesis (Dulay, Krashen, and Burt, 1982) describes the need for second-language learning to occur in an environment of low anxiety, to encourage the processing and learning of new information.

Dulay, Heidi, Stephen D. Krashen, and Mariana Burt. Language Two. Oxford, England: Oxford University Press, 1982.

affective neuroscience

A term used to describe the field of neuroscience investigating questions related to affect, including emotions and goals. Affective neuroscience questions are interrelated with questions in cognitive neuroscience; these fields are considered to overlap significantly.

affective neuroscientists

A term used to describe the field of neuroscience investigating questions related to affect, including emotions and goals. Affective neuroscience questions are interrelated with questions in cognitive neuroscience; these fields are considered to overlap significantly.

Agamemnon

The king of Mycenae and leader of the Greek army at Troy. Unlike Odysseus, Agamemnon was betrayed by his wife. She took a lover while Agamemnon was fighting at Troy, and together they killed Agamemnon when he returned home. His spirit meets with Odysseus in Hades.

Agave

The mother of Pentheus and aunt of Dionysus, who did not believe Dionysus was really the son of Zeus or a god himself; now, as the play begins, Agave is in thrall to Dionysus.

aggregate demand

The sum of expenditures on consumer goods and services, investment, and non-exports, i.e., all of demand within an economy.

aggregate demand curve

A curve, sloping downward to the right, that shows the level of real national output that will be demanded at various economy-wide price levels.

aggregate demand curve

A curve, sloping downward to the right, that shows the level of real national output that will be demanded at various economy-wide price levels.

aggregate demand curve

A curve, sloping downward to the right, that shows the level of real national output that will be demanded at various economy-wide price levels.

aggregate supply curve

A curve, sloping upward to the right, that shows the level of real national output that will be supplied at various economy-wide price levels.

aggregate supply curve

A curve, sloping upward to the right, that shows the level of real national output that will be supplied at various economy-wide price levels.

aggregate supply curve

A curve, sloping upward to the right, that shows the level of real national output that will be supplied at various economy-wide price levels.

Agoraphobia

An extreme fear of public places or open spaces.

Agrarianism

The belief that society and daily life should be structured around the cultivation of the soil. According to literary critic and historian M. Thomas Inge, Agrarians believe that the direct contact with nature that comes from farming will bring humans closer to God and encourage the values of “honor, manliness, self-reliance, courage, moral integrity, and hospitality.” Furthermore, Agrarians believe that urban life, capitalism, and technology destroy human dignity and independence while also encouraging vice and moral weakness. In the 1920s and 1930s a prominent group of southern writers–including John Crowe Ransom and Robert Penn Warren–loosely subscribed to the basic tenets of Agrarianism and therefore became known as the Southern Agrarians.

albedo

The fraction of electromagnetic radiation reflected after striking a surface.

Aleph-Null

Cantor called the cardinality of all the sets that can be put into one-to-one correspondence with the counting numbers aleph, or “Aleph Null.”

algebraic ideas

Algebraic ideas include patterns, variables, and functions, and are the building blocks of algebraic thinking.

algebraic structure

Algebraic structures are systems with objects and operations, and the rules or properties governing those operations, that can be used to calculate and solve equations.

algorithm

An algorithm is a recipe or a description of a mechanical set of steps for performing some task.

alienation

The experience of feeling outside mainstream culture. Most of the poets and movements in this unit explore a sense of alienation from society that has compelled them to search elsewhere for meaning. The emphasis on Eastern religion, alternative states of reality, hedonism, and nature suggests that these poets were seeking to redefine themselves and their generation through art.

alkali metal

The alkali metals are the chemical elements in the first column of the periodic table. They all have one valence electron. Alkali metals are commonly used atoms in atomic physics experiments for several reasons. Their structure is relatively simple and provides energy states that are convenient for laser cooling. Many of their transition frequencies match convenient laser sources. Also, the single valence electron’s magnetic moment allows the atoms to be easily trapped using magnetic fields, which is convenient for the evaporative cooling process necessary to reach ultracold temperatures.

alkali metals

The alkali metals are the chemical elements in the first column of the periodic table. They all have one valence electron. Alkali metals are commonly used atoms in atomic physics experiments for several reasons. Their structure is relatively simple and provides energy states that are convenient for laser cooling. Many of their transition frequencies match convenient laser sources. Also, the single valence electron’s magnetic moment allows the atoms to be easily trapped using magnetic fields, which is convenient for the evaporative cooling process necessary to reach ultracold temperatures.

All items requested are served, including toppings for the hamburger and side dishes

These descriptors list the evidence that must be presented to receive a certain score. They describe the level of performance. Good descriptors should be:

  • Brief, clear statements of observable behaviors or qualities,
  • written in language the student can easily understand.

allocation

An allocation is an arrangement for the values in a data set. For example, the data sets {1, 2, 3, 4, 5} and {3, 3, 3, 3, 3} each have a mean and a median equal to 3, but they are very different allocations. Allocation can also be used to describe the proximity of values to the mean; values may be closely distributed to or widely distributed from the mean, for example.

allocation of resources

Apportionment of productive assets among different uses.

Allotropes

Any two or more forms of the same element with different arrangements of atoms in their structures. For example, dioxygen (O2) and ozone (O3) are allotropes.

Alloy

A substance that contains more than one (usually metallic) element and has metallic properties, such as strength, conductivity, ductility, and malleability.

n

Not cooked to order (i.e. rare when well-done was requested)

These descriptors list the evidence that must be presented to receive a certain score. They describe the level of performance. Good descriptors should be:

  • Brief, clear statements of observable behaviors or qualities,
  • written in language the student can easily understand.

a

Alpha particle

A product of nuclear decay that is two protons and two neutrons, which form a particle with a structure identical to that of a helium nucleus with a charge of +2.

Alpha particles

Products of nuclear decay that are each made up of two protons and two neutrons, which form a particle with a structure identical to that of a helium nucleus with a charge of +2.

alpha rays

Alpha particles, also known as alpha rays, consist of two protons and two neutrons bound together into a particle identical to the nucleus of a helium atom. Alpha particles are emitted when certain radioactive atoms decay, and typically have an energy of about 5 MeV.

alpha rays

Alpha particles, also known as alpha rays, consist of two protons and two neutrons bound together into a particle identical to the nucleus of a helium atom. Alpha particles are emitted when certain radioactive atoms decay, and typically have an energy of about 5 MeV.

Alternative Hypothesis or H(a)

The claim in a significance test that we are trying to gather evidence for – the researcher’s point of view. The alternative hypothesis is contradictory to H0 and is judged the more plausible claim when H0 is rejected.

Alternative splicing

A biological process in which introns are removed from RNA in different combinations to produce different mRNA molecules from one gene; sometimes called “RNA alternative splicing.” 

Read more about this term in the Online Textbook:
Proteins and Proteomics: Genomics-Based Predictions of Cellular Proteins
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View Terms by Unit: Proteins and Proteomics

altitude

An altitude of a triangle is a line segment connecting a vertex to the line containing the opposite side and perpendicular to that side.

Amaranta (I)

Daughter of José Arcadio (I) and Úrsula. She becomes first embittered by her foster sister Rebeca when Rebeca wins the love of a handsome store owner, Pietro Crespi, then a bitter recluse after Rebeca chooses another. Amaranta herself rejects Pietro, who dies.

Amaranta Úrsula and Aureliano (IV)

Accidental incestuous lovers, Amaranta Úrsula and Aureliano (IV) are the last inhabitants of Macondo. Amaranta Úrsula erases Macondo from the Earth.

ambient

Surrounding, encircling.

ambiguity

Doubtfulness or uncertainness of interpretation. Much gothic literature is considered ambiguous insofar as it rarely presents a clear moral or message; it seems intended to be open to multiple meanings.

American Dream

The belief that a better life is possible for anyone in the United States. Because of its near-mythic status, the “American Dream” means different things to different people. One component of the American Dream is seen in the rags-to-riches tales of Benjamin Franklin and the nineteenth-century “Ragged Dick” stories. Another component is the notion of America as the “Gold Mountain,” put forth by Chinese immigrants who came to the western United States in the 1850s, during the Gold Rush years, to make their fortunes. Sadly, few of them earned enough to pay for passage home and instead became miners, railroad builders, fishermen, service workers, and menial laborers.

American Renaissance

Standard if limiting description of the flowering of American art and thought in the mid-nineteenth century. The restricted “canonical” version is usually thought to include Emerson, Thoreau, Hawthorne, Melville, Poe, and Dickinson.

Ammu

The twins’ mother, who suffers from the abuse and control of her father and then her husband. Divorced, living back in her home town, she is drifting through life when she too briefly finds happiness with Velutha.

Amorphous solid

A solid whose atoms or molecules are not arranged in regular, repeating patterns.

Amplitude

Learning Math: Patterns, Functions, and Algebra The amplitude of a cyclic function measures the height of the cyclic function, relative to its average. The amplitude can be determined by the formula: amplitude = (high – low) / 2.

Harmonious Math – The amount of displacement, as measured from the still surface line, is called a wave’s amplitude.

amplitude –

amusia

A general term referring to a collection of possible difficulties, acquired or congenital, related to music-related processing in relation to features such as rhythm, pitch, or tone.

amygdala

  • Neuroscience & the Classroom: Making Connections – The Unity of Emotion, Thinking, and Learning

    • An anatomical location in the brain positioned medially and distinctive for the almond-shape set of neurons. The region plays a critical role in emotion processing, in conjunction with other regions of the limbic system.

  • Discovering Psychology – Cognitive Neuroscience

    • A portion of the limbic system considered to be the center for certain memories, as well as for emotional reaction, such as aggression.

anaerobic

Describes an organism that is able to live without oxygen. Also used to describe environments that are devoid of gaseous or dissolved molecular oxygen.

Anaerobic respiration

A pathway of energy metabolism in which an alternate electron acceptor replaces oxygen. Organisms undergoing anaerobic respiration reduce nitrite (NO2-), nitrate (NO3-), or carbon dioxide (CO2) instead of oxygen.

Read more about this term in the Online Textbook:
Microbial Diversity: Microbes in Mines
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View Terms by Unit: Microbial Diversity

Anaplastic

A term used to describe cancer cells that divide rapidly and have little or no resemblance to normal cells.

Read more about this term in the Online Textbook:
None
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View Terms by Unit: Evolution and Phylogenetics
Microbial Diversity

Anecdotal records

Teaching Reading: K-2 Workshop – An anecdotal record documents an informal observation of what students are learning, their learning behaviors, social interactions, and academic performance. While anecdotal records may be brief recordings of single learning situations, they are most beneficial when they are gathered over time to reveal meaningful patterns that can guide the teacher’s planning. (Harp and Brewer, 2000). When taking an anecdotal record, teachers should record only what they see and hear without making judgments or interpretations. Because of their informal nature, anecdotal records are often used while observing children in learning centers. These observations allow teachers to assess children’s understanding of specific concepts as well as how children are using these concepts in reading and writing.

Teaching Reading: 3-5 Workshop – Anecdotal records are brief, written observations taken during regular instructional time that describe a literacy behavior or social interaction. They are most effective when gathered over time to reveal patterns of learning that will guide the teacher’s instruction. Teachers should record only what they see without making judgments or interpretations. Anecdotal records should focus on how students are progressing toward meeting grade-level benchmarks.

Angiogenesis

Blood vessel formation. Tumor angiogenesis is the growth of blood vessels from surrounding tissue to a solid tumor. This is caused by the release of chemicals by the tumor.

Read more about this term in the Online Textbook:
Cell Biology and Cancer: Tumor Biology
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View Terms by Unit: Evolution and Phylogenetics
Microbial Diversity

angle-angle-angle (AAA) similarity

The angle-angle-angle (AAA) similarity test says that if two triangles have corresponding angles that are congruent, then the triangles are similar. Because the sum of the angles in a triangle must be 180°, we really only need to know that two pairs of corresponding angles are congruent to know the triangles are similar.

angle-angle-angle (AAA) similarity

The angle-angle-angle (AAA) similarity test says that if two triangles have corresponding angles that are congruent, then the triangles are similar. Because the sum of the angles in a triangle must be 180°, we really only need to know that two pairs of corresponding angles are congruent to know the triangles are similar.

angle bisector

An angle bisector is a ray that cuts the angle exactly in half, making two equal angles.

angular momentum

In classical physics, the angular momentum of a system is the momentum associated with its rotational motion. It is defined as the system’s moment of inertia multiplied by its angular velocity. In quantum mechanics, a system’s total angular momentum is the sum of the angular momentum from its rotational motion (called orbital angular momentum) and its spin.

angular momentum

The measure of the extent to which an object will continue to rotate about a point unless acted upon by an external torque.

angular momentum

In classical physics, the angular momentum of a system is the momentum associated with its rotational motion. It is defined as the system’s moment of inertia multiplied by its angular velocity. In quantum mechanics, a system’s total angular momentum is the sum of the angular momentum from its rotational motion (called orbital angular momentum) and its spin.

animals

Issues in Animal Research: In response to heightened concerns about the use and treatment of animal participants, the American Psychological Association and other organizations involved in research have established ethical standards and guidelines for animal experimentation.

Anion

A negatively charged atom or molecule.

Anode

In an electrochemical cell, the electrode at which the oxidation half-reaction occurs.

Anodization

The description of a modified metal surface through reaction with another chemical component, forcing the metal surface to undergo oxidation (i.e., act as an anode).

Anodized

When a modified metal surface has a reaction with another chemical component, forcing the metal surface to undergo oxidation (i.e., act as an anode).

ANOVA

Analysis of variance (ANOVA) is a technique used to analyze variation in data in order to test whether three or more population means are equal.

anthropogenic

Describing effects or processes that are derived from human activities, as opposed to effects or processes that occur in the natural environment without human influences.

anti-usury laws

Laws that regulate the maximum interest rates that can be set for loans, in order to protect borrowers.

antiferromagnetic order

An antiferromagnet is a magnet in which the microscopic magnetic moments inside the material line up in a grid on which neighboring moments point in opposite directions. The interaction energy between two magnetic moments in an antiferromagnet is lower when the two moments point in opposite directions. This can lead to a frustrated system with multiple ground states.

antiferromagnetic order

An antiferromagnet is a magnet in which the microscopic magnetic moments inside the material line up in a grid on which neighboring moments point in opposite directions. The interaction energy between two magnetic moments in an antiferromagnet is lower when the two moments point in opposite directions. This can lead to a frustrated system with multiple ground states.

e

emergent behavior

Emergent behavior is behavior of a complex system that is not easily predicted from a microscopic description of the system’s constituent parts and the rules that govern them.

a

Antigen

A substance, often a protein or large polysaccharide, which is perceived as foreign by the body and stimulates an immune response. Components of microbes–such as cell walls, flagella, toxins, and the coats of viruses–can serve as antigens.

Read more about this term in the Online Textbook:
HIV and AIDS: The Immune System
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None
Related Images:
The Central Role of Helper T Cells
Cytoxic T Cell and Antigen Interaction
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Immune System Overview
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Antigenic shift

Changes in proteins in the outer envelope of a virus, resulting from the reassortment of viral genes. Major epidemics of influenza occur after antigenic shifts have taken place, because individuals are not immune to the substantially modified viruses.

Read more about this term in the Online Textbook:
Emerging Infectious Diseases: Animal Reservoirs
Related Terms:
Antigenic drift
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Antigenic shift in the influenza virus
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Antigenic Shift
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Influenza Infection
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View Terms by Unit: Emerging Infectious Diseases

antimatter

Antimatter is a type of matter predicted by Paul Dirac when he attempted to write down a version of quantum mechanics that incorporated Einstein’s theory of special relativity. In the Standard Model, every particle has a corresponding antiparticle that has the same mass but opposite electric charge, baryon number, and strangeness. When a particle meets its antiparticle counterpart, the pair annihilates: they disappear, and their total energy is converted into other particles.

Antimatter

A substance made of antiparticles, such as positrons and antiprotons, which have the same mass but opposite charge as their matter counterparts. When a particle and its antiparticle collide, both are annihilated and energy is released.

antimatter

Antimatter is a type of matter predicted by Paul Dirac when he attempted to write down a version of quantum mechanics that incorporated Einstein’s theory of special relativity. In the Standard Model, every particle has a corresponding antiparticle that has the same mass but opposite electric charge, baryon number, and strangeness. When a particle meets its antiparticle counterpart, the pair annihilates: they disappear, and their total energy is converted into other particles.

Antinous

The worst of the suitors and the first to die by Odysseus’s hand.

antiquark

An antiquark is the antimatter counterpart of a quark. See: antimatter, quark.

antiquark

An antiquark is the antimatter counterpart of a quark. See: antimatter, quark.

Anu

The sky god, chief god of Uruk.

Anxiety Disorder

A mental disorder in which an individual experiences physiological arousal and feelings of tension, tremor, shaking, and general apprehension without obvious reason or provocation.

Aoi

Genji’s first wife, given to him when she was twelve; she is a daughter of the Minister of the Left, one of the most powerful officials at court.

aphasia

An acquired disorder, most commonly the result of a stroke, which impairs a person’s ability to use and or understand language in service of communication. Difficulties can extend into reading and writing skills in addition to oral language.

Apnea

Heavy, disruptive snoring with repetitive pauses in breathing. Results include fatigue, memory loss, impotence, and high blood pressure.

Apocalypse

The end of the world as it is prophesied in the Bible, especially in the Book of Revelation. Viewing their experiences through the lens of biblical history, the Puritans understood themselves to be living in the “end time,” with Christ’s Second Coming at hand. They believed that their purity as a nation would actually bring about the Apocalypse, at which time Christ would return and reign for a millennium. Then, the earth would be destroyed, the elect would be ushered into heaven, and all others would be cast into hell. Puritan ministers performed complex analyses of scriptural predictions in order to pinpoint the exact day the Apocalypse would occur.

Apoptosis

A normal series of events in a cell that leads to its death. Also called programmed cell death.

Read more about this term in the Online Textbook:
Cell Biology and Cancer: Cell Cycle
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The Cell Cycle: Cyclins and Checkpoints
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p53’s Role in the Cell
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View Terms by Unit: Evolution and Phylogenetics
Microbial Diversity

Appearance

These elements represent the aspects of the work that will be evaluated, or the criteria for the assignment.

Aqueous solution

A solution where the solvent (primary component) is water.

aquifers

Underground formations, usually composed of sand, gravel, or permeable rock, capable of storing and yielding significant quantities of water.

aragonite

A carbonate mineral that forms naturally in almost all mollusk shells, as well as the calcareous endoskeleton of warm- and cold-water corals

Arcadio (II)

Arcadio (II) is the result of José (I)’s liaison with Pilar Ternera. When his father abandons him, Arcadio withdraws, and his life ends when he is executed by the Conservatives for joining his uncle Aureliano’s Liberal army.

archaea

The Habitable Planet, Unit 1: Many Planets, One Earth
A major division of microorganisms. Like bacteria, Archaea are single-celled organisms lacking nuclei and are therefore prokaryotes, classified as belonging to kingdom Monera in the traditional five-kingdom taxonomy.

Rediscovering Biology, Unit 4: Microbial Diversity
A domain of prokaryotic organisms that differ from bacteria. In contrast to bacteria, arachaea lack cell wall peptidoglycan, contain histone-like proteins, and possess chemically distinct cell membrane phospholipids.

area

Area is a measure of how much surface is covered by a figure.

Arjuna

The hero of the story; Arjuna is one of the five Pandava brothers who fight for their rightful place in their father’s kingdom. Arjuna’s father was a warrior god, but his greatest counselor is the god Krishna.

Arrhenius acid

Any molecule that can dissociate in an aqueous solution to produce a proton (H+).

Arrhenius base

Any molecule that can dissociate in an aqueous solution to produce a hydroxide ion (OH).

Art

the conscious production or arrangement of sounds, colors, forms, movements, or other elements in a manner that affects the sense of beauty

art deco

A style in decorative arts and architecture that emphasizes streamlined, geometric forms and an affinity to the shapes and materials of industrial products. A response to the elaborate, organic forms of the prevalent art nouveau style at the turn of the twentieth century, art deco designs such as the Chrysler Building often celebrated the machine. Beginning about 1910 and lasting until the mid-1930s, the art deco style influenced the design of many significant buildings and interiors.

artesian

Describes a confined aquifer containing groundwater that will flow upwards out of a well without the need for pumping.

Articulation

how individual notes are attacked

Asia Minor

This term is used to describe Western modern-day Turkey, the peninsula that is bounded by the Black Sea, the Aegean Sea, the Sea of Marmara, and the Mediterranean Sea.

Assessment

Teaching Reading: K-2 Workshop – Assessment refers to specific practices that are informal, classroom-based, and reflect the curriculum and daily instructional routines. Assessments are developed and used by teachers to determine children’s literacy needs and to plan appropriate instruction. Classroom assessments are authentic, multidimensional, collaborative, and ongoing. Often, teachers of young children will focus on one or two students each day to assess their literacy performance and behaviors throughout the day. Teachers assess both the process and products of learning during regular instructional times. This might include taking a Running Record during guided reading time, assessing comprehension with story retellings during class discussions, or completing a checklist for students in Writing Workshop.

Teaching Reading: 3-5 Workshop – Assessment refers to specific informal and formal classroom-based, teacher-developed practices that measure students’ understanding of the curriculum. Classroom assessments are authentic, multidimensional, collaborative, and ongoing. Assessments focus on both the process and the products of learning during regular instructional times. This might include a running record to focus on word analysis strategies, a retelling or discussion to focus on comprehension, or a written response to reading.

asset

Any item of economic value owned by an individual or corporation, especially that which could be converted to cash.

asset bubbles

Form when the prices of assets are over-inflated due to excess demand.

assimilation

Becoming part of the dominant culture and leaving behind characteristics and qualities that would designate one as different or “other.”

association

An association between two variables exists when a change in the values for one variable produces a systematic change in the other. If an increase in one variable tends to result in an increase in the other, the association is positive. If an increase in one variable tends to result in a decrease in the other, the association is negative.

associativity

Associativity is a property of some sets and binary operations where the order in which the operation is carried out may be manipulated to produce the same results. Addition is associative: (2 + 3) + 4 is equivalent to 2 + (3 + 4). Subtraction is not associative: 2 – (3 – 4) is not equivalent to (2 – 3) – 4.

Assumptions of the Linear Regression Model

  • The observed response y for any value of x varies according to a normal distribution. Repeated responses, y-values, are independent of each other.
  • The mean response, μy, has a straight-line relationship with x: μy = α + βx.
  • The standard deviation of y, σ, is the same for all values of x.

Athena

Daughter of Zeus and goddess of wisdom and battle. Athena is Odysseus’ patroness, and she helps him and his son Telemachus through their trials, eventually bringing Odysseus home to Ithaca.

atmospheric (adiabatic) lapse rate

The constant decline in temperature of an air parcel as it rises in the atmosphere due to pressure drop and gas expansion.

atmospheric lapse rate

The constant decline in temperature of an air parcel as it rises in the atmosphere due to pressure drop and gas expansion. Also called adiabatic lapse rate.

Atmospheric pressure

The force exerted by the weight of the atmosphere on a given unit area. Atmospheric pressure on Earth at sea level is 14.7 pounds per square inch (psi), 760 torr or 1 atm.

atomic fountain

An atomic fountain is a cloud of cold atoms that is given a push upward with a laser pulse. The laser is tuned to the right energy to transfer its momentum to the atoms, which fly up until gravity takes over, reversing their motion so they fall back down. The path the atoms take is analogous to the path of water in a fountain.

atomic number

The atomic number of an atom, denoted by Z, is the number of protons in its nucleus. The atomic number of an atom determines its place in the periodic table, and thus which chemical element it is.

atomic number

The atomic number of an atom, denoted by Z, is the number of protons in its nucleus. The atomic number of an atom determines its place in the periodic table, and thus which chemical element it is.

atomic number

The atomic number of an atom, denoted by Z, is the number of protons in its nucleus. The atomic number of an atom determines its place in the periodic table, and thus which chemical element it is.

attention deficit hyperactivity disorder (ADHD)

A diagnostic category describing a developmental disability that primarily impacts attention capacities with secondary difficulties most often observed in behavior and learning environments. Clinicians rely on criteria for reaching a diagnosis of ADHD using the Diagnostic and Statistical Manual of Mental Disorders (DSM), most typically.

Aureliano Segundo and José Arcadio Segundo

The twin sons of Arcadio (José Arcadio II). José Arcadio Segundo witnesses the massacre of banana workers, which no one else believes happened.

Authentic literacy

Students engage in authentic literacy activities when they read and write for real purposes rather than to satisfy classroom assignments. They use literacy to learn or to develop understanding of specific concepts and are motivated to read and write based on their interests and questions. Authentic literacy activities often are designed to focus on a specific audience to communicate ideas for a shared understanding as opposed to completing worksheets or answering questions for school assignments.

authentic materials

Authentic materials are resources that have been developed specifically for native speakers. These include print, audio, and visual materials.

authentic text

Authentic texts are print, audio, and visual documents created and used by native speakers. Examples include books, Web sites, articles, artwork, films, folktales, music, and advertisements.

Author’s Chair

The Author’s Chair is a special place for students to sit as they share their finished writing with the class. This is a time to celebrate children’s accomplishments and encourage peer interactions and response.

autism spectrum disorders

A diagnostic category describing a developmental disability that primarily impacts socioemotional functioning. Clinicians rely on criteria described by the Diagnostic and Statistical Manual of Mental Disorders (DSM), most typically, in three categories: social interaction, verbal and nonverbal communication, and repetitive behaviors or interests.

auto-American-biography

A term coined by literary critic Sacvan Bercovitch for an autobiographical text in which the narrator self-consciously foregrounds his narrative construction of himself as an ideal American citizen. Benjamin Franklin’s Autobiography is often understood as an auto-American-biography.

Autoinducers

Molecules involved in quorum sensing that regulate mRNA production for specific genes in response to population density.

Read more about this term in the Online Textbook:
Microbial Diversity: Biofilm Formation and Bacterial Communication
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Quorum sensing
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The Biofilm Lifecycle
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automatic stabilizers

Structural features of the economy that tend by themselves to stabilize national output, without the help of legislation or government policy measures.

Automaticity

Automaticity is fast, effortless, and accurate word recognition that grows out ot repetition and practice. Automaticity does not refer to reading with expression or evidence of comprehension. Games and activities using lists of high-frequency words, personal word lists, and word walls help students develop automaticity. Automaticity allows students to concentrate more on other aspects of reading, such as comprehension. (Adapted from Armbruster, Lehr, and Osborn. Put Reading First, 22 and 24).

Autonomic Arousal

The involuntary change in bodily activities that relates to the peripheral nervous system, such as a person’s heart rate or sweating, in response to physical or psychological stimuli.

Availability Heuristic

A general principle used in reasoning under conditions of uncertainty; based on dependence on one’s personal experiences.

average product of an input

Total output divided by the amount of input used to produce this amount of output.

average product of labor

Total output per unit of labor.

axes

The axes of a graph are the base (or zero) values of two quantities that are being compared in a coordinate graph. The horizontal axis is often referred to as the x-axis and the vertical axis is often referred to as the y-axis.

Axiomatic Systems

The system that Euclid used in The Elements—beginning with the most basic assumptions and making only logically allowed steps in order to come up with propositions or theorems—is what is known today as an axiomatic system.

axion

The axion is a hypothetical particle that naturally arises in the solution to the strong-CP problem proposed by Peccei and Quinn in 1977. Axions are electrically neutral, and experiments have shown that their mass must be less than 1 eV. While they are relatively light particles, slow-moving axions could be produced in copious amounts in the early universe, and thus could be a significant component of the dark matter.

Ayemenem

The small town on the southeast coast of India where the Kochamma family have lived for generations.

b

B factory

A B factory is a particle physics apparatus designed to create B mesons, which are mesons that contain one bottom antiquark and one quark of a different flavor. In a B factory, electrons and positrons from an accelerator collide, producing B mesons and anti-B mesons in equal amounts. The science goal of the B factories is to study CP violation in B meson decay, which may shed light on why the universe contains more matter than antimatter.

B factory

A B factory is a particle physics apparatus designed to create B mesons, which are mesons that contain one bottom antiquark and one quark of a different flavor. In a B factory, electrons and positrons from an accelerator collide, producing B mesons and anti-B mesons in equal amounts. The science goal of the B factories is to study CP violation in B meson decay, which may shed light on why the universe contains more matter than antimatter.

Baby Kochamma

The twins’ great-aunt is an old maid whose only passion in her youth was a hopeless love for an Irish monk. She lives her life in bitterness, hating Rahel and Estha, and helps cause the death of Velutha.

BAC

Bacterial artificial chromosome. A plasmid vector used to clone large fragments of DNA (average size of 150 kb) in E. coli.


Read more about this term in the Online Textbook:
Genomics: Sequencing a Genome

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Bacchae

(or Bacchants) The all-female followers of Bacchus/Dionysus.

Background knowledge

Background knowledge is the collection of concepts and ideas one has for a given topic or situation based on personal experiences and/or reading. Background knowledge is directly related to effective reading comprehension; thus, it is important for teachers to develop and access this knowledge before, during, and after reading. The background knowledge of English language learners may differ from that of mainstream learners.

backtracking

Backtracking is a method of solving equations that involves undoing the operations in an equation to work backward from an output to an input.

backward design

Backward design, also called backward planning, is a pedagogical approach to unit or lesson planning in which the teacher first identifies the desired end task or product, then works in reverse from the assessment task(s) to identify the prerequisite learning tasks.

backward planning

In backward planning, also called backward design, the teacher plans a unit or lesson by first identifying the desired end task or product, then working in reverse to identify the prerequisite learning tasks and benchmark assessments.

bacteria

Microscopic organisms whose single cells have neither a membrane-bounded nucleus nor other membrane-bounded organelles like mitochondria and chloroplasts.

Bacterial artificial chromosome (BAC)

A plasmid vector used to clone large fragments of DNA (average size of 150 kb) in E. coli.

Bacteriocin

Proteins produced by some bacteria, which inhibit the growth of other strains of the same organism or related species. Genes for bacteriocins may reside on plasmids.

Read more about this term in the Online Textbook:
Emerging Infectious Diseases: The Human Body as an Ecosystem
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Balance

Balance describes the harmonious combination of elements (texture, color, form, and shape) in an image.

balance-of-payments deficit

The difference between the quantity supplied and the quantity demanded of a currency when the currency is overvalued (that is, priced above its equilibrium price).

balance-of-payments surplus

The difference between the quantity demanded and the quantity supplied of a currency when the currency is undervalued (that is, priced below its equilibrium price).

balance sheet

A quantitative summary of a company’s financial condition at a specific point in time, including assets, liabilities, and net worth.

balanced budget

A budget in which tax revenues equal government expenditures.

Balancing selection

Selection that actively maintains more than one variant of a gene in a population.

Read more about this term in the Online Textbook:
Human Evolution: Malaria, Sickle Cell Anemia, and Balancing Selection
Related Terms:
Alternative splicing
Polymerase chain reaction (PCR)
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DeCode asthma pedigree figure
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Single Nucleotide Polymorphisms (SNPs)
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View Terms by Unit: Human Evolution

bank run

Takes place when the customers of a bank fear that the bank will become insolvent, and so rush to the bank to take out their money as quickly as possible to avoid losing it.

Bar Chart

Graph of a frequency distribution for categorical data. Each category is represented by a bar whose area is proportional to the frequency, relative frequency, or percent of that category. If the categorical variable is ordinal, the logical order of the categories should be preserved in the bar chart.

barriers to entry

Obstacles that make it more difficult for new competitors to enter an area of business, e.g., high start-up costs.

baryon

The term “baryon” refers to any particle in the Standard Model that is made of three quarks. Murray Gell-Mann arranged the baryons into a periodic table-like structure according to their baryon number and strangeness (see Unit 1, Fig. 1). Protons and neutrons are the most familiar baryons.

baryon

The term “baryon” refers to any particle in the Standard Model that is made of three quarks. Murray Gell-Mann arranged the baryons into a periodic table-like structure according to their baryon number and strangeness (see Unit 1, Fig. 1). Protons and neutrons are the most familiar baryons.

baryon

The term “baryon” refers to any particle in the Standard Model that is made of three quarks. Murray Gell-Mann arranged the baryons into a periodic table-like structure according to their baryon number and strangeness (see Unit 1, Fig. 1). Protons and neutrons are the most familiar baryons.

baryon number

Every particle composed of quarks is assigned a baryon number. A particle’s baryon number is one-third the number of quarks minus the number of antiquarks in the particle. Baryon number is conserved in collisions, which means that the total baryon number of incoming particles is the same as the total baryon number of the particles produced in the collision.