Biology Midterm

• The goal of science is to investigate, to understand the natural world, and to make predictions
• 7 characteristics of living things are they are made up of cells, they reproduce, based on a universal genetic code, grow and develop, obtain and use materials and energy, respond to their environment, and maintain a stable internal environment
• 3 unifying principles of biology are cell theory, gene theory, and homeostasis
• Cell theory - all living things are made up of cells
• gene theory - the idea that characteristics of living things are controlled by genes
• Homeostasis - keeping things constant
• The scientific method is to observe, research, form hypothesis, test hypothesis, draw conclusion, and communicate results
• If the conclusion does not match the hypothesis go back to research
• The parts of an experiment are the control, manipulated, and responding variable
• Control - held constant and won't influence the outcome
• Manipulated - independent; factor changed by researcher
• Responding - dependent; factor researcher predicts will change
• Common measurement system - a decimal system of measurement whose measurements are based on certain physical standards and are based on multiples of 10
• Scientific theories - supported by evidence collected by may scientists
• Radioactive isotopes can be used to treat cancers, kill bacteria, and can be used as labels or tracers (to follow movements in organisms)
• The levels of organization in living things are cells, tissue, organs, organ system, organism, population, community, ecosystem, biome, and biosphere
• Carbon is significant because it has 4 valence electrons, bonds with other carbon atoms, can have 4 bonds (max), and can easily make single, double, and triple bonds
• Glucose - a sugar formula - C6H12O6
• • Conservation of Matter - Matter is neither created nor destroyed
• • Conservation of Mass - Mass can neither be created nor destroyed but can be transformed
• • Activation Energy - The minimum amount of energy needed to start a reaction
• • Enzymes - Proteins that act like biological catalysts
• • Some characteristics of water are it is tasteless, colorless, transparent, one of the most unique liquids, stays liquid at many temps, is found in us and makes up 70% of the planet, and expands when frozen
• • Neuralization reaction - HCl + NaOH → H2O +NaCl
• • pH scale - a scale used to measure acidity and goes from 0-14
• • The 4 groups of organic compounds are carbohydrates, lipids, proteins, and nucleic acids
• • The different levels of organization in ecology are organism, population, community, ecosystem, biome, and biosphere
• • Competitive exclusion principle - a given habitat may contain many different species, but each has its own niche. No two species have the same niches
• • The way energy moves in an environment is in one direction (from sun to autotrophs to heterotrophs)
• • The different trophic levels - producer, primary, secondary, tertiary, quaternary, (after producer is all consumers)