MTTC Integrated Science Secondary (94) 100% verified(SCORED A+)

What are the 5 steps in the Scientific Method? - ANSWER 1. Identify a problem or pose a question based on an observation. 2. Formulate a hypotheses. 3. Conduct experiments or tests the hypotheses. 4. Observe and record the results. 5. Draw a conclusion (was the hypothesis correct?). * peer review is also important. Metric Unit deca (da): - ANSWER x 10^1 Metric Unit hecto (h): - ANSWER x 10^2 Metric Unit kilo (k): - ANSWER x 10^3 Metric Unit mega (M): - ANSWER x 10^6 Metric Unit giga (G): - ANSWER x 10^9 Metric Unit deci (d): - ANSWER x 10^-1 Metric Unit centi (c): - ANSWER x 10^-2 Metric Unit milli (m): - ANSWER x 10^-3 Metric Unit micro (µ): - ANSWER x 10^-6 Metric Unit nano (n): - ANSWER x 10^-9 Metric Unit pico (p) - ANSWER x 10^-12 What is an Independent Variable and what axis is it plotted on in a graph? - ANSWER *The variable that acts as a control or does not change during an experiment. *x axis What is an Dependent Variable and what axis is it plotted on in a graph? - ANSWER *The variable that changes in response to the independent variable. This change is measured to determine the effect of the independent variable on the dependent variable. *y axis What are random experimental errors? - ANSWER Errors that are not consistent across the data set. * can result in collected data that does not seem to fit and may be wildly different from the rest of the data, or they may result in data that is indistinguishable from the rest. * may be the result of outside factors that are not considered variables *referred to as noise What are systematic experimental errors? - ANSWER An error that will show up consistently across a sample or data set. *may be the result of a flaw in the experiment design or instrumentation *affects the average *known as a bias Chemistry lab fire hazards - ANSWER Volatile solvents: ether, acetone, benzene *store in open beaker or Erlenmeyer flask *use extreme caution around sparks * heat in fume hood with a steam bath (not on a hot plate) Chemistry lab chemical burns - ANSWER Mineral acids and alkalis are corrosive to the skin and eyes *acid halides and phenols are corrosive and often toxic Chemistry lab toxic chemicals that can be absorbed through the skin - ANSWER dimethyl sulfoxide (DMSO) nitrobenzene Chemistry lab toxic fume inhalation - ANSWER acetyl chloride- severely irritate membranes in the eyes, nose, throat, and lungs benzyl chloride- eye irritation and tears Simple microscope - ANSWER a microscope that contains only one lens Compound microscope - ANSWER Microscope that contains two or more lenses to increase total magnification (usually 3 lenses) *multiply each magnification to obtain total magnification Accuracy of balances - ANSWER Most accurate- Electronic triple- beam Least- Spring balance Chromotography - ANSWER Is the separation of a mobile phase carrying a mixture that moves in contact with a selectively absorbent stationary phase. Analyte - ANSWER The substance or chemical being analyzed or detected in a specimen reagent - ANSWER a chemical agent for use in chemical reactions centrifuge - ANSWER an apparatus that uses centrifugal force to separate particles from a suspension Heterogeneous mixture - ANSWER A mixture in which different materials can be distinguished easily precipitate - ANSWER A solid that forms and settles out of a liquid mixture supernatant - ANSWER liquid above the precipitate that remains after centrifugation that can be removed from the precipitate with a pipet- also called centrifugate Spectrophotometry - ANSWER An analytical method for identifying a substance by its selective absorption of different wavelengths of light. Electrophoresis - ANSWER A technique for separating macromolecules (proteins, RNA, DNA) on a gel using an electric field. Calorimetry - ANSWER The measurement of heat flow (into or out of a system) as the result of a chemical reaction or physical process. Titration - ANSWER a measured amount of a solution of unknown concentration is added to a known volume of a second solution until the reaction between them is just complete Charles Robert Darwin - ANSWER Author of "On the Origin of Species" and founder of modern evolution theory. Natural Selection, natural change, gradual change, and common descent *d.1882 Anton van Leeuwnhoek - ANSWER made his own lenses found unicellular organisms cell theory (all cells come from preexisting cells) *d. 1723 Carl Linnaeus - ANSWER "Father of Taxonomy"; established his classification of living things; famous for animal naming system of binomial nomenclature *d. 1778 Barbara McClintock - ANSWER Nobel Prize winner who found that genes could jump from one place on chromosome to another Created the first genetic map for maize *d. 1992 Gregor Johann Mendel - ANSWER Austrian monk, and botanist who proved the existence of dominant and recessive characteristics in living things (pea plants). "Father of Genetics" *d. 1884 James Watson and Francis Crick - ANSWER Co-discovered the double helix structure of DNA in which two strands were wound around each other--led to discovery of how DNA is replicated. *d. 2004 Mean - ANSWER Average (sum of a list of numbers divided by the number of numbers) Median - ANSWER Middle Number Mode - ANSWER Most common Range - ANSWER Distance between highest and lowest scores in a set of data. Regression analysis - ANSWER Measures the impact of a set of variables on another variable Standard deviation - ANSWER A statistical measure of how far away each value is, on average, from the mean. *determines the confidence one can have in their conclusions eukaryotic cell - ANSWER A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles. Examples of organisms with these cells are protists, plants, fungi, and animals. Prokaryotic Cell - ANSWER A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles; found only in the domains Bacteria and Archaea. Nuclear parts of a cell - ANSWER Nucleus, Chromosomes, Chromatin, Ribosomes, Nucleolus, Nuclear envelope, Nuclear Pores, and Nucleoplasm Nucleus - ANSWER a small structure that contains the chromosomes and regulates the DNA of a cell. Chromosomes - ANSWER A threadlike, gene-carrying structure found in the nucleus. Each chromosome consists of one very long DNA molecule and associated proteins. Chromatin - ANSWER DNA and protein that makes up chromosomes Nucleolus - ANSWER This structure contained within the nucleus consists of protein. It is small, round, does not have a membrane, is involved in protein synthesis, and synthesizes and stores RNA Nuclear envelope - ANSWER A double membrane that encloses the nucleus, made of lipids, perforated with pores that regulate traffic with the cytoplasm Nuclear pores - ANSWER structures in the nuclear envelope that allow passage of certain materials between the cell nucleus and the cytoplasm Nucleoplasm - ANSWER Fluid containing ions, enzymes, nucleotides, and some RNA Ribosomes - ANSWER A cell organelle composed of RNA and protein; the site of protein synthesis. Golgi complex - ANSWER This is involved in synthesizing materials such as proteins that are transported out of the cell. It is located near the nucleus and consists of layers of membranes. Vacuoles - ANSWER Membrane-bound sacs for storage, digestion, and waste removal * 1 large in plants *numerous small in animals Vesicle - ANSWER A membrane bound sac that contains materials involved in transport of the cell. Cytoskeleton - ANSWER a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence Microtubules - ANSWER A hollow rod composed of tubulin proteins that makes up part of the cytoskeleton in all eukaryotic cells and is found in cilia and flagella. Cytosol - ANSWER Fluid portion of the cytoplasm. Represents about half the volume of a eukaryotic cell. Contains thousands of enzymes involved in intermediate metabolism and crowded with ribosomes making proteins. Cytoplasm - ANSWER General term for the liquid inside the cell but outside of the nuclear envelope. Consists of organelles, cytoskeleton, and cytosol Cell membrane - ANSWER A thin, flexible barrier around a cell; regulates what enters an Metric Unit deca (da): - ANSWER x 10^1