Essay on Biology Midterm

Essay on Biology Midterm Essay on Biology Midterm Chapter 1- Scientific Thinking * Science is an intellectual activity, encompassing observation, description, experimentation, and explanation of natural phenomena. * Biological issues permeate all aspects of our lives. To make wise decisions, it is essential for individuals and societies to attain biological literacy. * Superstition is the irrational belief that actions that are not logically related to a course of events can influence its outcome. * Because it is empirical, rational, testable, repeatable, and self-correcting, the scientific method is a particularly effective approach. * Scientific Method: * -Make observations * -Formulate a hypothesis * -Devise a testable prediction * -Conduct a critical experiment * -Draw conclusions and make revisions * A hypothesis is a proposed explanation for an observed phenomenon and must generate a testable prediction * Null hypothesis a lack of relationship between two factors * A critical experiment makes it possible to determine if a hypothesis is correct. * Theory is an explanatory hypothesis for natural phenomena that is exceptionally well supported by the empirical data. * Treatment: any experimental condition applied to the research subject * Experimental group: a group of subjects who are exposed to a particular treatment * Control group: subjects who are treated identically to the experimental group, where they are not exposed to the treatment * Variables: the characteristics of an experimental system that are subject to change * Placebo effect: people respond favorably to any treatment * Blind experimental: subjects do not know which treatment they are receiving * Double-blind experiment: neither the subjects or experiment know treatment * Biases can influence our behavior and collection and interpretation of data * Independent variable: measurable entity that is available at the start of a process (x-axis) * Dependent variable: measurable entity that is created by the process observed (y-axis) * Positive correlation: one variable incre ases, so does the other * Visual displays of data condense large amounts of information and can aid in the presentation and exploration of the data * Statistics can help us evaluate whether differences between a treatment group and control group can be attributed to the treatment rather than a random chance. * Pseudoscience: individuals make scientific claims that are not supported * Anecdotal observations: based on just one or few observations * Although the scientific method may be the most effective, it can’t give us insight into non-quantifiable, subjective information. Chapter 2- Chemistry * Element: substance that cannot be broken down chemically into any other substances * Atom: a bit of matter that cannot be subdivided any further without losing essential properties * Nucleus: center of the atom, made up of protons and neutrons * Protons: positive electric charge * Neutrons: no electric charge * Electrons: negative electric charge * Atomic Mass: the mass of an atom; made up of the combined mass of all of its protons and neutrons * Particles with the same charge repel each other, opposites attract each other * Atomic number: corresponds to have many protons it has * The mass of an atom is usually about double the element’s atomic number * The number of neutrons in the nucleus is usually equal to the number of protons, and protons and neutrons have approximately the same mass * Isotope: an atom that has extra neutrons or fewer neutrons than the number of protons * An atom’s charge doesn’t change in an isotope because neutrons have no electric c harge * Radioactive atoms: atoms that break down spontaneously after created and in the process of decomposition they release, at a constant rate, a particle carrying a lot of energy. * Elements in the human body: