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146 Cards in this Set
- Front
- Back
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Science
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the investigation of natural phenomena through observation, theoretical explanation, and experimentation, or the knowledge produced by such investigation
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Observation
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an act or instance of noticing or perceiving
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Inference
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the deriving of one idea from another
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Hypothesis
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a mere assumption or guess
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Controlled experiment
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an experiment or trial that uses controls, usually separating the subjects into one or more control groups and experimental groups
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Independent variable
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a variable that is intentionally changed to observe its effect on the dependent variable
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Dependent variable
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the event studied and expected to change when the independent variable is changed
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Control group
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any group used as a control in a statistical experiment
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Data
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a series of observations, measurements, or facts; information
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Theory
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a system of rules, procedures, and assumptions used to produce a result
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Bias
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mental tendency or inclination
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Biology
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the study of living organisms, including their structure, functioning, evolution, distribution, and interrelationships
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DNA
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deoxyribonucleic acid: an extremely long macromolecule that is the main component of chromosomes and is the material that transfers genetic characteristics in all life forms, constructed of two nucleotide strands coiled around each other in a ladderlike arrangement with the sidepieces composed of alternating phosphate and deoxyribose units and the rungs composed of the purine and pyrimidine bases adenine, guanine, cytosine, and thymine
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Stimulus
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something that stimulates or acts as an incentive
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Sexual Reproduction
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reproduction involving the fusion of a male and female haploid gamete
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Asexual reproduction
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reproduction occurring without the sexual union of male and female gametes
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Homeostasis
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the tendency of an organism or cell to regulate its internal conditions
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Metabolism
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the total of the chemical reactions that maintain the life of a living thing
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Biosphere
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the thin outer shell of the Earth and the inner layers of its atmosphere; the place where all living systems are found
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Atom
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a unit of matter; the smallest unit of a chemical element
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Nucleus
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the central region of the cell, in which DNA is stored
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Electron
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an elementary particle with a negative charge and a very small mass
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Element
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any material that cannot be broken down into more fundamental substances (such as carbon, hydrogen, iron, or oxygen)
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Isotope
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different forms of the same element, with nuclei that have the same number of protons but different numbers of neutrons
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Compound
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a substance containing two or more elements in definite proportions
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Ionic bond
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a chemical bond in which one atom gives up an electron to another, thereby generating an electrical force that holds the atoms together
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Ion
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an atom that has either lost or gained one or more electrons, so that it has an electrical charge
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Covalent bond
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the bond formed by the sharing of a pair of electrons by two atoms
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Molecule
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a combination of two or more atoms held together by a force between them
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van der Waals forces
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weak, nonspecific forces between molecules
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Hydrogen bond
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a chemical bond in which a hydrogen atom of one molecule is attracted to an electronegative atom
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Cohesion
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the molecular attraction or joining of the surfaces of two pieces of the same substance
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Adhesion
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the force of attraction that causes two different substances to join
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Mixture
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a substance consisting of two or more substances mixed together without any chemical bonding between them
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Solution
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a uniform mixture of one solid, liquid, or gas with another solid, liquid, or gas
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Solute
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a substance that is dissolved in another substance, forming a solution
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Solvent suspension
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the state in which the particles of a substance are mixed with a fluid but are undissolved
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pH scale
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provides a measure on a scale from 0 to 14 of the acidity or alkalinity of a solution (where 7 is neutral and greater than 7 is more basic and less than 7 is more acidic)
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Acid
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a sour-tasting material (usually in a solution) that dissolves metals and other materials and has a pH of 0 to 7.
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Base
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any of a number of bitter-tasting, caustic materials that has a pH of 7 to 14
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Buffer
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the components of a solution that can neutralize either an acid or a base and thus maintain a constant pH
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Monomer
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a compound whose molecules can join together to form a polymer
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Polymer
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a long molecule made up of a chain of smaller, simpler molecules
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Carbohydrate
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any of a large class of organic compounds consisting of carbon, hydrogen, and oxygen, usually with the ratio 1:2:1
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Monosaccharide
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a simple sugar that does not hydrolyze to yield other sugars (such as glucose or fructose)
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Lipid
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any of a group of organic compounds, including the fats, oils, waxes, sterols, and triglycerides, that are insoluble in water but soluble in common organic solvents
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Nucleic acid
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any of a group of long, linear macromolecules, either DNA or various types of RNA, that carry genetic information directing all cellular functions
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Nucleotide
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any of a group of organic compounds composed of a nucleoside linked to a phosphate group
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Protein
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any of a large class of complex organic chemical compounds that are essential for life
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Amino acid
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any of a large number of compounds found in living cells that contain carbon, oxygen, hydrogen, and nitrogen, and join together to form proteins
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Chemical reaction
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a process in which atoms of the same or different elements rearrange themselves to form a new substance
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Reactant
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a substance participating in a chemical reaction, especially one present at the start of the reaction
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Product
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a substance resulting from a chemical reaction
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Activation energy
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the least amount of energy needed for a chemical reaction to take place
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Catalyst
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a substance that causes a chemical reaction to occur but is not itself involved in the reaction
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Enzyme
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a protein molecule that helps other organic molecules enter into chemical reactions with one another but is itself unaffected by these reactions
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Substrate
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the substance acted upon by an enzyme
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Cell
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the basic unit of all living things
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Cell theory
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the theory that cells form the fundamental structural and functional units of all living organisms
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Cell membrane
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the structure separating an animal cell from its environment or a plant cell from its cell wall
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Nucleus
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the central region of the cell in which DNA is stored
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Eukaryote
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an organism whose cells contain a nucleus
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Prokaryote
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any organism having cells in each of which the genetic material is in a single DNA chain, not enclosed in a nucleus
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Cytoplasm
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the material within a cell that is not contained in the nucleus or other organelles
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Organelle
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a structure or part that is enclosed within its own membrane inside a cell and has a particular function
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Vacuole
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a cavity within the cytoplasm of a cell, surrounded by a single membrane and containing fluid, food, or metabolic waste
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Lysosome
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a cell organelle that is surrounded by a membrane, has an acidic interior, and contains hydrolytic enzymes that break down food molecules
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Cytoskeleton
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the inner structural elements, or backbone, of a cell
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Centriole
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a small, cylindrical cell organelle that divides in perpendicular fashion during mitosis
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Ribosome
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a small, ball-like structure in the cell, made of proteins and RNA molecules, that serves as a platform on which the cell's proteins are made
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Endoplasmic Reticulum
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an organelle consisting of a network of membranes within the cytoplasm of eukaryotic cells that is important in protein synthesis and folding and is involved in the transport of cellular materials
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Golgi apparatus
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an organelle in eukaryotic cells that stores and modifies proteins for specific functions and prepares them for transport to other parts of the cell
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Chloroplast
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a chlorophyll-containing organelle found in algal and green plant cells
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Mitochondrion
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the cell organelle where much of cellular respiration takes place; the “power plant” of the cell
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Cell wall
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the rigid outer covering of a plant cell, composed mainly of cellulose and lying outside the cell membrane
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Lipid bilayer
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the basic structure of a cell membrane consisting of a double layer of phospholipid molecules
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Selectively permeable
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the control a cell membrane has over what can cross it
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Diffusion
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the spreading of atoms or molecules of one substance through those of another, especially into liquids or gases
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Facilitated diffusion
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a process by which substances are transported across cell membranes by means of protein carrier molecules
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Osmosis
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the seeping of a fluid through a seemingly solid barrier, such as a cell wall or a rubber sheet
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Isotonic
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two solutions having the same osmotic pressure
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Hypertonic
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a solution of higher osmotic pressure than another solution with which it is compared
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Hypotonic
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having a lower osmotic pressure than that of a solution
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Tissue
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a large mass of similar cells that make up a part of an organism and perform a specific function
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Organ
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a specific part of the body that performs a specific function
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Organ system
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a group of organs that work together to carry out a particular task
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Adenosine triphosphate
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the high-energy molecule that stores the energy we need to function
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Heterotroph
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an organism that cannot manufacture its own food and instead obtains its food and energy by taking in organic substances
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Autotroph
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any organism capable of self-nourishment by using inorganic materials as a source of nutrients and using photosynthesis or chemosynthesis as a source of energy
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Photosynthesis
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used by green plants of the energy in sunlight to carry out chemical reactions
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Pigment
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any substance whose presence in the tissues or cells of animals or plants that gives them color
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Chlorophyll
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the complex chemical that gives a plant its green color and plays an important role in the conversion of sunlight into energy for the plant
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Thylakoid
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a saclike membrane that contains the chlorophyll in cyanobacteria and in the chloroplasts of plant cells and green algae
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Stroma light-dependent reaction
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the first stage of photosynthesis by which plants capture and store energy from sunlight
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Light-independent reaction
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the stage in photosynthesis in which chemical reactions convert carbon dioxide and other compounds into glucose
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Cellular respiration
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the chemical process that generates most of the energy in the cell
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Aerobic
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organism that requires the presence of oxygen to live
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Anaerobic
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an organism living in the absence of air or free oxygen
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Glycolysis
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the process in cell metabolism by which carbohydrates and sugars, especially glucose, are broken down, producing ATP and pyruvic acid
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Krebs cycle
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a series of chemical reactions that occur in most aerobic organisms and are part of the process of aerobic cell metabolism, by which glucose and other molecules are broken down in the presence of oxygen into carbon dioxide and water to release chemical energy in the form of ATP
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Matrix
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the component of an animal or plant tissue that is outside the cells
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Chromosome
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a structure in all living cells that consists of a single molecule of DNA bonded to various proteins and that carries the genes determining heredity
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Chromatin
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the substance distributed in the nucleus of a cell that condenses to form chromosomes during cell division
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Cell cycle
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the growth cycle of eukaryotic cells
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Interphase
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the stage in the development of a cell following mitosis or meiosis, during which the nucleus is not dividing
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Mitosis
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division of a single cell into two identical “daughter” cells
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Cytokinesis
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division of the cytoplasm of a cell, occurring at the end of mitosis or meiosis
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Prophase centromere
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in mitosis, specialized regions on centromeres called kinetochores attach chromosomes to spindle polar fibers
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Chromatid
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either of the two strands into which a chromosome divides during mitosis
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Centriole metaphase
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the stage of cell division in which the duplicated centrioles become aligned along the center of the cell
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Anaphase
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the stage of cell division in mitosis or meiosis in which the doubled set of chromosomes separates into two identical groups that move to opposite ends of the cell
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Telophase
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the final stage of mitosis or meiosis during which the chromosomes of daughter cells are grouped in new nuclei
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Scientific experimentation can most likely answer
which question regarding a bird population? A. How does a baby bird learn to recognize the type of food it can eat? B. How does the type of food a bird eats affect the number of offspring it produces? C. What is the relationship between beak size and the number of offspring a bird produces? D. Why does a bird with a very short beak produce more offspring than a bird with a very long beak? |
C
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Ebola virus is a potentially deadly virus in the blood
which causes Ebola fever. Ebola virus is often spread by monkeys. Scientists used 2 groups of monkey kidney cells in an experiment to confirm the first human case of Ebola fever. The scientists inoculated cells in Group I with samples of the Ebola virus taken from a human with Ebola fever. They did not inoculate the cells in Group 2. What was the control group in the experiment? A. The Ebola virus B. All of the monkey kidney cells C. Monkey kidney cells in Group 1 D. Monkey kidney cells in Group 2 |
D
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Biology students carried out an experiment to
determine if a certain fertilizer increased the height of plants The students selected 4 types of plants and planted 10 seeds of each type. Five seeds of each type were treated with fertilizer and 5 seeds of each type were not treated with fertilizer. All other conditions were identical. The students recorded the plant height after 120 days, as shown in the table. A. Castor bean B. Okra C. Radish D. Tomato |
D
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A biologist conducted an experiment to determine
whether the survival of tadpoles was affected by the pH of the pond water in which they live. His results are shown in this graph. Based on this graph, the difference between the percentage of surviving tadpoles is greatest for which 2 consecutive pH values? A. 5.5 and 6.0 B. 6.0 and 6.5 C. 6.5 and 7.0 D. 7.5 and 8.0 |
B
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Two students wanted to estimate and compare the density of 2 species of plants in a grassland habitat. Student I randomly located 10 sampling plots and counted the number of plants of each species in each sampling plot. Each sampling plot was 1 m^2. The number of individuals of each species that Student I counted in each sampling plot were:
Species A: 9, 8, 15, 21, 8, 4, 25, 1, 11, 0 Species B: 15, 14, 15, 16, 15, 17, 14, 15, 18, 16 Student 2 was in a hurry and decided to locate his 10 sampling plots in the areas with the least amount of vegetation. He counted the number of plants of each species in each 1 m sampling plot. The number of individuals of each species that Student 2 counted in each sampling plot were: Species A: 2, 4, 1, 0, 0, 4, 2, 1, 1, 0 Species B: 13, 15, 14, 15, 14, 14, 15, 15, 14, 14 Based on the data collected by Student 1, what is the mean density of Species A in the grassland habitat he surveyed? A. 1 .5 individuals/m^2 B. 5.9 individuals/m^2 C. 10.2 individuals/m^2 D. 15.5 individuals/m^2 |
C
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Two students wanted to estimate and compare the density of 2 species of plants in a grassland habitat. Student I randomly located 10 sampling plots and counted the number of plants of each species in each sampling plot. Each sampling plot was 1 m^2. The number of individuals of each species that Student I counted in each sampling plot were:
Species A: 9, 8, 15, 21, 8, 4, 25, 1, 11, 0 Species B: 15, 14, 15, 16, 15, 17, 14, 15, 18, 16 Student 2 was in a hurry and decided to locate his 10 sampling plots in the areas with the least amount of vegetation. He counted the number of plants of each species in each 1 m sampling plot. The number of individuals of each species that Student 2 counted in each sampling plot were: Species A: 2, 4, 1, 0, 0, 4, 2, 1, 1, 0 Species B: 13, 15, 14, 15, 14, 14, 15, 15, 14, 14 Based on the data collected by Student 2, what is the mean density of Species B in the grassland habitat he surveyed? A. 1 .5 individuals/m^2 B. 5.9 individuals/m^2 C. 10.2 individuals/m^2 D. 14.3 individuals/m^2 |
D
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For years, runoff from a nearby industrial plant has entered a certain lake. The runoff causes seasonal blooms of algae in the lake. These algae are short-lived and die off quickly. Which of the following graphs most likely illustrates the growth pattern of this algal population from the beginning of the spring seasonal bloom to the end of the resultant die-off of the algal population?
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A
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Dr. Graham has written a paper on the internal
temperature of nests of alligator eggs. His data show that temperature determines the sex of the hatchlings. What is the best method of validating the reliability of Dr. Graham’s experiment? A. Dr. Graham should clearly document the experimental process. B. Dr. Graham should repeat the experiment at another time of year. C. Several scientists should repeat the experiment using Dr. Graham’s design. D. Several scientists should observe Dr. Graham as he repeats the experiment. |
C
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In an experiment, 6,000 people with a common cold
who drank orange juice daily had symptoms that lasted an average of 4 days. Another 6,000 people with a common cold who did not drink orange juice daily had symptoms that lasted an average of 7 days. Scientists repeated the experiment 3 times with the same results. They concluded that orange juice reduces the length of the common cold. Was this conclusion valid, and why? A. Yes, because vitamin C is a known common cold cure. B. Yes, because scientists repeated the experiment. C. No, because the sample size was too small. D. No, because some of the people who drank orange juice did not feel better. |
B
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If a researcher makes an experimental observation
that is contrary to well-established scientific understanding, what should the next step be? A. Ignoring the results of the experiment if they support the hypothesis B. Re-evaluating the procedure and replicating the experiment C. Publishing the research in a well-known journal D. Manipulating the data so it conforms to current understanding |
B
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Before Gregor Mendel’s experiments with pea plants, many scientists believed that offspring inherited a blend of parental traits. Mendel’s results contradicted this theory. What aspect of the nature and philosophy of science does this change in thinking exemplify?
A. Prior knowledge affects scientific observation. B. Scientific knowledge ¡s more often wrong than right. C. Scientists guess when formulating scientific theories. D. Scientific knowledge changes as new data becomes available. |
D
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Mark saw a documentary on the harmful effects of cigarette smoke and wants to learn more. He consults many types of resources, but knows that not all contain sound scientific information. Which resource likely contains the LEAST reliable information?
A. Scientific journal B. Peer-reviewed online magazine C. Library reference D. Internet discussion group |
D
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After learning about viruses in Biology class, Sam decides to have his cat vaccinated against feline leukemia virus. According to cell theory, are viruses, such as feline leukemia, considered living things?
A. Yes, because they can reproduce. B. Yes, because they are composed of cells. C. No, because they cannot adapt to their environment. D. No, because they are not composed of cells. |
D
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Which sequence is in order from the simplest level
of organization to the most complex? A. Muscle, erythrocyte, lipid, mitochondrion, carbon B. Carbon, lipid, erythrocyte, mitochondrion, muscle C. Muscle, mitochondrion, lipid, erythrocyte, carbon D. Carbon, lipid, mitochondrion, erythrocyte, muscle |
D
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A veterinary technician administered subcutaneous fluids to a cat. She administered a total of 600 mL of fluid over a period of 7 days with an initial dose of 150 mL on Day 1. The doses on Days 2—7 were different from the initial dose, but equal in volume to each other. How much liquid did she administer on the second day?
A. 75mL B. 86mL C. 150 mL D. 600 mL |
A
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In glycerol (C3H8O3), there is a hydroxyl group (OH)
bound to each of the 3 carbon atoms. The bond between the oxygen atom of a hydroxyl group and a carbon atom in glycerol is best classified as what type of bond? A. Covalent B. Hydrogen C. Intermolecular D. Ionic |
A
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In this series of metabolic reactions, Compound R
is converted into Compound A, and Enzyme X then catalyzes the conversion of Compound A into Compounds B and D. Compound B is converted to Compound C. Assume that Compound C inhibits Enzyme X and that Compound C is not consumed in a subsequent reaction. As the concentration of Compound C increases, the rate of production of which compound is LEAST likely to decrease? A. A B. B C. C D. D |
A
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Honey is composed mostly of glucose and fructose. What property of water explains why honey dissolves easily in water?
A. Water exhibits strong cohesion. B. Water has a high specific heat. C. Water is a polar molecule. D. Water is easily ionized. |
C
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When a small neutral molecule becomes an ion, in which way is it better able to function?
A. Dissolving in blood plasma B. Sharing electrons with other ions C. Combining with ions of similar charges D. Passing through a cell’s plasma membrane |
A
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Which is the LEAST likely trait of an organic molecule?
A. The molecules may exist as isomers. B. The backbone is linear, cyclic, or branched. C. Ionic bonds are present between the atoms. D. Functional groups, such as alcohols, are present. |
C
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Which of the following solutions has the greatest
concentration of hydroxide ions (OH-) ? A. Urine (pH 6.0) B. Rainwater (pH 5.5) C. Tomato juice (pH 4.0) D. Gastric juice (pH 2.0) |
A
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The presence of which of the following structures in a cell would indicate that the cell is NOT a photosynthetic bacterium?
A. Cell wall B. Chloroplast C. DNA D. Ribosome |
B
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Naomi adds cycloheximide to cells grown in a test
tube. Within minutes, she identifies short incomplete segments of proteins in the cells. On which organelle lie does cycloheximide act? A. Endoplasmic reticulum B. Golgi apparatus C. Nucleus D. Ribosome |
D
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A scientist adds an antibody specific to the actin
protein to a prepared culture of macrophages. The macrophages exhibit active movement before, but not after, treatment. What is the most accurate conclusion about the function of actin? A. Actin depolymerizes microtubular arrays. B. Actin plays a role ¡n the function of pseudopodia. C. Actin disrupts cellular activities in the cytoskeleton. D. Actin guides the movement of chromosomes in macrophages. |
B
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By what process does a sodium ion exit a cell through the plasma membrane?
A. Active transport B. Exocytosis C. Facilitated diffusion D. Osmosis |
A
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The cytoplasm of red blood cells has a higher concentration of Na+ than does pure water. Suppose a biologist places a red blood cell in pure water. Is there a net flow of water molecules into or out of the red blood cell, and by which process does this net flow of water occur?
A. Out of the cell; osmosis B. Into the cell; osmosis C. Out of the cell; active transport D. Into the cell; active transport |
B
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During aerobic cellular respiration, in which of the following locations do ATP molecules form?
A. Cytosol only B. Mitochondrial matrix only C. Mitochondrial matrix and outer mitochondrial membrane only D. Cytosol, mitochondrial matrix, and outer mitochondrial membrane only |
B
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In biology class, Keesha places a suspension of the green algae Chlorella in a growth chamber. She turns the light on in the growth chamber, then measures the change ¡n the amount of CO2 in the growth chamber over the next 15 minutes. She then repeats the experiment, using a growth chamber that is devoid of light. She finds that the amount of CO2 in the lighted growth chamber decreases over time, while the amount of CO2 ¡n the dark growth chamber increases over time. The most likely explanation for her results is that, in the absence of light, CO2:
A. consumption by photosynthesis is greater than CO2 production by cellular respiration. B. consumption by cellular respiration ¡s greater than CO2 production by photosynthesis. C. production by photosynthesis is greater than CO2 consumption by cellular respiration. D. production by cellular respiration is greater than CO2 consumption by photosynthesis. |
B
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These diagrams represent different stages of animal cell division. From start to finish, what is the correct order of the stages?
A. 2, 4, 3, 1 B. 2, 3, 4, 1 C. 3, 2, 1, 4 D. 3, 1, 2, 4 |
A
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Plant cells contain both a cell wall and a cell membrane. What is the composition of the cell wall, and where is it located in relation to the cell membrane?
A. Cellulose, inside the cell membrane B. Cellulose, outside the cell membrane C. Glucose, inside the cell membrane D. Glucose, outside the cell membrane |
B
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While performing an experiment using green spinach leaves, Jamie identifies chlorophyll and pigments of several other colors. What is the most accurate conclusion Jamie can make about the pigments in spinach leaves?
A. Chlorophyll decomposes to reveal other pigments. B. Chlorophyll absorbs light while other pigments reflect light. C. Chlorophyll passes light energy to other pigments in the leaves. D. Chlorophyll appears in higher concentrations than other pigments. |
D
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Marco grows algae in the presence of a substance that stops the light-independent reactions of photosynthesis. As a result, which molecules will the light-dependent reactions eventually stop producing?
A. ADP and NADP+ B. ADP and NADPH C. ATP and NADP+ D. ATP and NADPH |
D
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Which experimental design would provide scientists with the best data for investigating which type of feed yields the greatest gain in lean muscle mass in cattle?
A. Test 5 different types of cows with the same feed mixture and measure their weight gain at the end of a 6-week trial. B. Test 5 similar groups of cows with 5 different feed mixtures and measure their weight gain at the end of a 6-week trial. C. Test 5 similar groups of cows with the same feed mixture, give each group varying amounts of feed, and measure their weight gain at the end of a 6-week trial. D. Test 5 different types of cows with 5 different feed mixtures, give each group varying amounts of feed, and measure their weight gain at the end of a 6-week trial. |
B
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A microbiologist wants to determine whether a certain chemical affects the growth rate of bacteria. Which method would be most efficient and reliable for tracking the bacteria population’s growth rate each hr for 24 hrs?
A. Counting individual bacterial cells B. Determining the mass of the tube containing the bacteria C. Measuring the light absorbance of the populations in the tubes using a spectrophotometer D. Calculating the size of the population using the average doubling time of the bacteria in the absence of the chemical |
C
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