Biology Eoc Vocab

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mitosis

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the usual method of cell division, characterized typically by the resolving of the chromatin of the nucleus into a threadlike form, which condenses into chromosomes, each of which separates longitudinally into two parts, one part of each chromosome being retained in each of two new cells resulting from the original cell.

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meiosis

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part of the process of gamete formation, consisting of chromosome conjugation and two cell divisions, in the course of which the diploid chromosome number becomes reduced to the haploid.

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asexual

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having no sex or sexual organs.
OR independent of sexual processes, esp. not involving the union of male and female germ cells.

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sexual

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having sexual organs or reproducing by processes involving both sexes.

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homologous

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of the same chemical type, but differing by a fixed increment of an atom or a constant group of atoms: Methyl and ethyl alcohols are homologous.

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allelic

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any of several forms of a gene, usually arising through mutation, that are responsible for hereditary variation.

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dominate

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to rule over; govern; control.

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recessive

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that one of a pair of alternative alleles whose effect is masked by the activity of the second when both are present in the same cell or organism.

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homozygous

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having identical pairs of genes for any given pair of hereditary characteristics.

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genotype

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the genetic makeup of an organism or group of organisms with reference to a single trait, set of traits, or an entire complex of traits.

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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: the genetic information of DNA is encoded in the sequence of the bases and is transcribed as the strands unwind and replicate.

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RNA

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ribonucleic acid: any of a class of single-stranded molecules transcribed from DNA in the cell nucleus or in the mitochondrion or chloroplast, containing along the strand a linear sequence of nucleotide bases that is complementary to the DNA strand from which it is transcribed: the composition of the RNA molecule is identical with that of DNA except for the substitution of the sugar ribose for deoxyribose and the substitution of the nucleotide base uracil for thymine.

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cell cycle

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the cycle of growth and asexual reproduction of a cell, consisting of interphase followed in actively dividing cells by prophase, metaphase, anaphase, and telophase.

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DNA replication

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The process whereby a copy of a DNA molecule is made and thus the genetic information it contains is duplicated. The parental double stranded dna molecule is replicated semi conservatively, i.e. Each copy contains one of the original strands paired with a newly synthesised strand that is complementary in terms of AT and GC base pairing. Though in this sense conceptually simple, mechanistically a complex process involving a number of enzymes.

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transcription

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the process by which genetic information on a strand of DNA is used to synthesize a strand of complementary RNA.

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mRNA

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messenger RNA.

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tRNA

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transfer RNA -a small RNA molecule, consisting of a strand of nucleotides folded into a clover-leaf shape, that picks up an unattached amino acid within the cell cytoplasm and conveys it to the ribosome for protein synthesis. Abbreviation: tRNA

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rRNA

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a type of RNA, distinguished by its length and abundance, functioning in protein synthesis as a component of ribosomes.

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protein synthesis

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the process by which amino acids are linearly arranged into proteins through the involvement of ribosomal RNA, transfer RNA, messenger RNA, and various enzymes.

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chromosome

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any of several threadlike bodies, consisting of chromatin, that carry the genes in a linear order: the human species has 23 pairs, designated 1 to 22 in order of decreasing size and X and Y for the female and male sex chromosomes respectively.

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gene

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the basic physical unit of heredity; a linear sequence of nucleotides along a segment of DNA that provides the coded instructions for synthesis of RNA, which, when translated into protein, leads to the expression of hereditary character.

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codon

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a triplet of adjacent nucleotides in the messenger RNA chain that codes for a specific amino acid in the synthesis of a protein molecule.

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hydrolysis

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chemical decomposition in which a compound is split into other compounds by reacting with water.

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ATP and ADP cycle

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everything to do with the storage and use of energy in living things.

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cellular respiration

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the oxidation of organic compounds that occurs within cells, producing energy for cellular processes.

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aerobic

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(of an organism or tissue) requiring the presence of air or free oxygen for life.

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kreb cycle

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A cycle of reactions catalyzed by enzymes in which pyruvate derived from nutrients and converted to Acetyl Coenzyme A is completely oxidized and broken down into carbon dioxide and water to produce high-energy phosphate compounds, which are the source of cellular energy.

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electron transport

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the stepwise transfer of electrons from one carrier molecule, as a flavoprotein or a cytochrome, to another along the respiratory chain and ultimately to oxygen during the aerobic production of ATP.

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anaerobic

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(of an organism or tissue) living in the absence of air or free oxygen.

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autotrophic

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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, as most plants and certain bacteria and protists.

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heterotrophic

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capable of utilizing only organic materials as a source of food.

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photosynthesis

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(esp. in plants) the synthesis of complex organic materials, esp. carbohydrates, from carbon dioxide, water, and inorganic salts, using sunlight as the source of energy and with the aid of chlorophyll and associated pigments.

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chlorophyl

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the green coloring matter of leaves and plants, essential to the production of carbohydrates by photosynthesis, and occurring in a bluish-black form, C55H72MgN4O5 (chlorophyll a), and a dark-green form, C55H70MgN4O6 (chlorophyll b).

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chloroplast

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a plastid containing chlorophyll.

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passive trasport

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The movement of a chemical substance across a cell membrane without expenditure of energy by the cell, as in diffusion.

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active transport

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the movement of ions or molecules across a cellular membrane from a lower to a higher concentration, requiring the consumption of energy.

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chemical reaction

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a process in which one or more substances are changed into others

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reactant

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any substance that undergoes a chemical change in a given reaction.

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product

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a substance obtained from another substance through chemical change.

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exothermic reaction

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a chemical reaction accompanied by the evolution of heat

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endothermic reaction

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a chemical reaction accompanied by the absorption of heat

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active energy

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The least amount of energy needed for a chemical reaction to take place. Some elements and compounds react together naturally just by being close to each other, and their activation energy is zero. Others will react together only after a certain amount of energy is added to them. Striking a match on the side of a matchbox, for example, provides the activation energy (in the form of heat produced by friction) necessary for the chemicals in the match to ignite. Activation energy is usually expressed in terms of joules per mole of reactants.

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enzyme

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any of various proteins, as pepsin, originating from living cells and capable of producing certain chemical changes in organic substances by catalytic action, as in digestion.

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substrate

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the substance acted upon by an enzyme.

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activestate

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An atom or nucleus which possesses more energy than its ground state energy.

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buffer

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any substance or mixture of compounds that, added to a solution, is capable of neutralizing both acids and bases without appreciably changing the original acidity or alkalinity of the solution.
OR Also called buffer solution. a solution containing such a substance.

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homeostasis

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the tendency of a system, esp. the physiological system of higher animals, to maintain internal stability, owing to the coordinated response of its parts to any situation or stimulus tending to disturb its normal condition or function.

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pH

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(organic chemistry) A phenyl ring.

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acid

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a compound usually having a sour taste and capable of neutralizing alkalis and reddening blue litmus paper, containing hydrogen that can be replaced by a metal or an electropositive group to form a salt, or containing an atom that can accept a pair of electrons from a base. Acids are proton donors that yield hydronium ions in water solution, or electron-pair acceptors that combine with electron-pair donors or bases.

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base

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A. a compound that reacts with an acid to form a salt, as ammonia, calcium hydroxide, or certain nitrogen-containing organic compounds.
B. the hydroxide of a metal or of an electropositive element or group.
C. a group or molecule that takes up or accepts protons.
D. a molecule or ion containing an atom with a free pair of electrons that can be donated to an acid; an electron-pair donor.
E. any of the purine and pyrimidine compounds found in nucleic acids: the purines adenine and guanine and the pyrimidines cytosine, thymine, and uracil.

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metabolism

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the sum of the physical and chemical processes in an organism by which its material substance is produced, maintained, and destroyed, and by which energy is made available.

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diffusion

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Also called migration. an intermingling of molecules, ions, etc., resulting from random thermal agitation, as in the dispersion of a vapor in air.

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osmosis

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the tendency of a fluid, usually water, to pass through a semipermeable membrane into a solution where the solvent concentration is higher, thus equalizing the concentrations of materials on either side of the membrane.

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facilitated diffusion

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in cell biology, a process by which substances are transported across cell membranes by means of protein carrier molecules; also called facilitated transport

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Concentration gradient

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the gradual difference in the concentration of solutes in a solution between two regions. In biology, a gradient results from an unequal distribution of ions across the cell membrane. When this happens, solutes move along a concentration gradient. This kind of movement is called diffusion.

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hypotonic

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noting a solution of lower osmotic pressure than another solution with which it is compared

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hypertonic

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noting a solution of higher osmotic pressure than another solution with which it is compared

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equilibrium

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the condition existing when a chemical reaction and its reverse reaction proceed at equal rates.

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isotonic

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noting or pertaining to a muscular contraction in which constant tension continues while the length of the muscle decreases, as during mechanical work.

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cell

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a usually microscopic structure containing nuclear and cytoplasmic material enclosed by a semipermeable membrane and, in plants, a cell wall; the basic structural unit of all organisms.

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organelle

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a specialized part of a cell having some specific function; a cell organ.

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nucleus

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a specialized, usually spherical mass of protoplasm encased in a double membrane, and found in most living eukaryotic cells, directing their growth, metabolism, and reproduction, and functioning in the transmission of genic characters.

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cell membrane

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the semipermeable membrane enclosing the cytoplasm of a cell.

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semipermeable

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permeable only to certain small molecules

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cytoplasm

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the cell substance between the cell membrane and the nucleus, containing the cytosol, organelles, cytoskeleton, and various particles.

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ribosome

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the cell substance between the cell membrane and the nucleus, containing the cytosol, organelles, cytoskeleton, and various particles.

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cell wall

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the definite boundary or wall that is part of the outer structure of certain cells, as a plant cell.

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vacuole

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a membrane-bound cavity within a cell, often containing a watery liquid or secretion.

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placid

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Pleased; contented; unruffied; undisturbed; serene; peaceful; tranquil; quiet; gentle

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polysaccharide

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a carbohydrate, as starch, inulin, or cellulose, containing more than three monosaccharide units per molecule, the units being attached to each other in the manner of acetals, and therefore capable of hydrolysis by acids or enzymes to monosaccharides.

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nucleotide

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any of a group of molecules that, when linked together, form the building blocks of DNA or RNA: composed of a phosphate group, the bases adenine, cytosine, guanine, and thymine, and a pentose sugar, in RNA the thymine base being replaced by uracil.

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glycerol

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a colorless, odorless, syrupy, sweet liquid, C3H8O3, usually obtained by the saponification of natural fats and oils: used for sweetening and preserving food, in the manufacture of cosmetics, perfumes, inks, and certain glues and cements, as a solvent and automobile antifreeze, and in medicine in suppositories and skin emollients.

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fatty acid

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any of a class of aliphatic acids, esp. palmitic, stearic, or oleic acid, consisting of a long hydrocarbon chain ending in a carboxyl group that bonds to glycerol to form a fat.

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adenine

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any of a class of aliphatic acids, esp. palmitic, stearic, or oleic acid, consisting of a long hydrocarbon chain ending in a carboxyl group that bonds to glycerol to form a fat.

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thymine

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a pyrimidine base, C5H6N2O2, that is one of the principal components of DNA, in which it is paired with adenine. Symbol: T

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amino acid

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any of a class of organic compounds that contains at least one amino group, –NH2, and one carboxyl group, –COOH: the alpha-amino acids, RCH(NH2)COOH, are the building blocks from which proteins are constructed.

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monosaccharide

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a carbohydrate that does not hydrolyze, as glucose, fructose, or ribose, occurring naturally or obtained by the hydrolysis of glycosides or polysaccharides.

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lipid

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any of a group of organic compounds that are greasy to the touch, insoluble in water, and soluble in alcohol and ether: lipids comprise the fats and other esters with analogous properties and constitute, with proteins and carbohydrates, the chief structural components of living cells.

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phospholipid

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any of a group of fatty compounds, as lecithin, composed of phosphoric esters, and occurring in living cells.

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carbohydrate

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any of a class of organic compounds that are polyhydroxy aldehydes or polyhydroxy ketones, or change to such substances on simple chemical transformations, as hydrolysis, oxidation, or reduction, and that form the supporting tissues of plants and are important food for animals and people.

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protein

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any of numerous, highly varied organic molecules constituting a large portion of the mass of every life form and necessary in the diet of all animals and other nonphotosynthesizing organisms, composed of 20 or more amino acids linked in a genetically controlled linear sequence into one or more long polypeptide chains, the final shape and other properties of each protein being determined by the side chains of the amino acids and their chemical attachments: proteins include such specialized forms as collagen for supportive tissue, hemoglobin for transport, antibodies for immune defense, and enzymes for metabolism.

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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: composed of linked nucleotides.

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tissue

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an aggregate of similar cells and cell products forming a definite kind of structural material with a specific function, in a multicellular organism.

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organ

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a grouping of tissues into a distinct structure, as a heart or kidney in animals or a leaf or stamen in plants, that performs a specialized task.

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scientific question

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Of, or having to do with science, as in scientific studies, scientific method, a scientific approach.
OR Agreeing with or consistent with the principles or methods used in science.

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biology

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the science of life or living matter in all its forms and phenomena, esp. with reference to origin, growth, reproduction, structure, and behavior.

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scientific method

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a method of research in which a problem is identified, relevant data are gathered, a hypothesis is formulated from these data, and the hypothesis is empirically tested.

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hypothesis

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a proposition, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either asserted merely as a provisional conjecture to guide investigation (working hypothesis) or accepted as highly probable in the light of established facts.

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experimental design

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A branch of statistics that attempts to outline the way in which experiments should be carried out so the data gathered will have statistical value.

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variable

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deviating from the usual type, as a species or a specific character.

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independent variable

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The variable that is manipulated in an experiment.

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dependent variable

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The variable whose value is measured to determine the extent of the effect of another variable to it, as in an experiment.

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control group

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(in an experiment or clinical trial) a group of subjects closely resembling the treatment group in many demographic variables but not receiving the active medication or factor under study and thereby serving as a comparison group when treatment results are evaluated.

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theory

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A conjecture, an opinion, a speculation or an assumption based on limited information or experience, not necessarily on facts.

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law

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A scientific generalization based on empirical observations of physical behavior.

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Eukaryotic

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Of, or pertaining to, or characteristic of a eukaryote, which is basically an organism possessing a membrane-bound nucleus.

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prokarotic

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any cellular organism that has no nuclear membrane, no organelles in the cytoplasm except ribosomes, and has its genetic material in the form of single continuous strands forming coils or loops, characteristic of all organisms in the kingdom Monera, as the bacteria and blue-green algae.

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unicellular

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any cellular organism that has no nuclear membrane, no organelles in the cytoplasm except ribosomes, and has its genetic material in the form of single continuous strands forming coils or loops, characteristic of all organisms in the kingdom Monera, as the bacteria and blue-green algae.

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multicellular

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composed of several or many cells.

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organ system

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A group of organs that work together to carry out a particular task.