ch. 1 Hypothesis-driven scientific study Flashcards
scientific method and science assumptions
we assume that natural forces acting now have always acted, that the fundamental nature of the universe has not changed since its inception, and that it is not changing now. (NO CHANGE). no one “scientific method”.
deductive reasoning
= applies general principles to predict specific results
ex. greek scientist Eratosthenes used Euclidean geometry and deductive reasoning to accurately estimate the circumference of the earth.
= reasoning of math and philosophy and it is used to test the validity of general ideas in a branches of knowledge.
ex. biologist uses deductive reasoning to infer the species of a specimen from its characteristics.
inductive reasoning
=logic flows in opposite direction– from specific to general
=uses specific observations to construct general scientific principles.
-leads to generalizations that can then be tested.
ex. first became important in 1600s in Europe when francis bacon and issac newton use the results of experiments to infer general principles about the world.
fruit fly ex.
hypothesis steps
problem-> collect observations-> general hypothesis-> general testable predictions-> experimental test of predictions-> falsification + reject hypothesis/ hypothesis supported + replication and new tests = hypothesis supported!
(inductive reasoning leads to development of one or more potential explanations).
experiment
=test of a hypothesis
-may encounter many hypotheses that have withstood the test of the experiment. others will be revised as new observations are made.
biology= constant state of change
controls (variables, control group, and experimental treatment)
-scientists are interested in learning about processes that are influenced by many factors or variables.
-To evaluate alternative hypotheses, keep the variable of interest constant in a control group and alter it in the experimental treatment; isolate the effects of a single variable so any difference in the outcome must result from the influence of this variable.
predictions
for a hypothesis to be successful, you must make testable predictions. when proposing a hypothesis, keep in mind that it may explain everything you have observed but also be wrong.
reductionism
=understand a complex system by reducing it to its working parts
=unraveling complexity of cellular metabolism by concentrating on individual pathways and specific enzymes.
has limits when applied to living systems, one of which is that enzymes do not always behave exactly the same in isolation as they do in their normal cellular context
models
-provide a way to organize how we think about a problem
-get us closer to larger picture and away from extreme reductionist approach
scientific theory
=body of interconnected concepts, supported by scientific reasoning and experimental evidence, that explains the facts in some area of study.
science theory=solid ground of science and evidence (accepted general principle)
general public=lack of knowledge/ a guess
basic vs applied research
basic
-extend boundaries of what we know
-usually work at universities and their research is usually supported by grants from agencies and foundations
-contributes to growing body of scientific knowledge and it provides the foundation for applied research
applied
-work in industry (manufacture of food additives, creation of new drugs, or testing of environmental quality)
analogous
structures that are similar in function but different in evolutionary origin
homologous
- refers to similar structures that have same evolutionary origin
- refers to a pari of the same kind of chromosome in a diploid cell
homologous
- refers to similar structures that have the same evolutionary origin
- refers to a pair of the same kind of chromosome in a diploid cell
