BIOL111 Principles of Biology Laboratory Exam 1 Study Guide (1) (1).docx

Order of steps in the scientific method: - Observation: Identify a problem to investigate. - Question: Formulate a question based on the observation. - Research: Gather existing information related to the question. - Hypothesis: Develop a testable statement. - Experiment: Design and c...

Order of steps in the scientific method: - Observation: Identify a problem to investigate. - Question: Formulate a question based on the observation. - Research: Gather existing information related to the question. - Hypothesis: Develop a testable statement. - Experiment: Design and conduct experiments to test the hypothesis. - Analysis: Analyze the data that was collected. - Conclusion: Draw conclusions based on analysis (determine if the hypothesis was supported or refuted). - Communication: Share the results with the scientific community. Inductive vs deductive reasoning - Inductive: Uses a specific example to generate a general theory. - Deductive: Uses a general principle to determine a specific outcome. Components of good experimental design (controls, replicates, bias) - A testable, falsifiable, repeatable hypothesis - Both independent and dependent variables - A control group (a group that receives no manipulation) - Minimal bias Difference between hypothesis, theory and law - A hypothesis is a testable statement with limited evidence. - A theory is something that is backed by evidence. - A law is a natural phenomenon What organism was used in the experiment? - Planaria Mean - Average of all numbers Range - Biggest to smallest numbers Mode - Number that shows up the most Median - The number in the middle of the data set Proteins - Made of amino acids - Snakes - Biuret Test Carbohydrates - Made of saccharides - Hexagons - Benedict's Test for smaller sugar - IKI Test for larger sugar Lipids - Made of fatty acids or triglycerides - Chains of C (Saturated and Unsaturated fats) - Sudan IV Test Nucleic Acids - Made of nucleotides - Has the phosphate - Dische Test What is an indicator test? - Identifies a substance, usually by adding something that causes a reaction with what is being looked for What do emulsifiers do? - Allows to liquids to mix and prevents separation Basic enzyme characteristics - Specificity - Efficiency (significantly speeds up reactions) - Reusability What is denaturation and what causes it? - Denaturation is the act of disabling an enzyme - Causes: temperature and pH change What is an inhibitor and how does it work? - An inhibitor prevents an enzyme from working on the substrate - Competitive inhibitors physically block the enzyme from reaching the active site - Non-competitive inhibitors bind elsewhere What enzyme did we use in the lab - What was used to measure light absorbance? - Spectrophotometer What effect does temperature have on enzyme activity? - Denatures the enzyme, slows the reaction What effect does an inhibitor have on enzyme activity? - Prevents the reaction What effect does pH have on enzyme activity? - Denatures the enzyme What is the difference between dependent and independent variables, and how should they be graphed? (Independent is something we change, and dependent is what changed because of that) - Independent variables are something that we change - Dependent variables are what is measured Diffusion: what is it and how is it affected by molecular weight? - Diffusion is when molecules spread out due to being attracted to areas of lower concentration - Heavier molecular weight results in slower diffusion, lighter molecular weight is quicker What is Brownian motion? - Movement of particles due to kinetic energy What is Osmosis? - Osmosis is the movement of water through the cell membrane from high concentration to low concentration Understand Hyper-Hypo-and Isotonic solutions and how water would move into and out of a cell - Hypertonic: Solution has higher concentration than what is inside of the cell - Hypotonic: Solution has lower concentration than what is inside of the cell - Isotonic: Solution has the same concentration as what is inside of the cell Lysis and turgor pressure, what are they and what would cause them - Lysis: Bursting of cells from absorbing too much water - Turgor Pressure: the balance of pressure of fluid within the cell walls Plasmolysis and Crenation, what are they and what would cause them - Plasmolysis: Water moves out of the cell - Crenation: When a cell loses so much water that it shrivels What is cytoplasmic streaming and give examples - Movement of fluid of the cytoplasm within the cells - Distributes nutrients, moves organelles such as chlorophyll, and assists in movement