Biology Review Flashcards
What is at the heart of science?
- Inquiry
Ex. What causes stomach ulcers?
What are the two main steps to inquiry?
- making observations
- forming hypotheses
How are we able to describe natural structures and processes?
- through observations and analysis of data
What is data?
- Recorded observations
What is qualitative data?
- Observations with your senses
What is quantitative data?
- Measured using instruments
What is inductive reasoning?
- Deriving generalizations based on a large number of specific observation
What is a hypothesis? GENERALLY
- Prediction that can be tested by recording more observations or experiments
What is the structure of a hypothesis?
- often heard as “if … , then …, (because)” but not mandatory
If = manipulated variable
Then = responding variable
Because = optional explanation
What does the results say about the hypothesis?
- results could either support or refute the hypothesis
- Never say the hypothesis is correct, say the data supports/refute the hypothesis
What is deductive reasoning?
Specific results derived from general premises
Ex. All athletes workout. John is an athlete, therefore he works out.
- deductive is a lot more elaborate, kind of like a step-by-step putting generalized ideas together
What type of hypothesis should you always start with?
Null hypothesis
What is a null hypothesis? (2)
Ho Is a hypothesis which is the researcher tries to disprove/project/nullify.
- The hypothesis that shows there is no difference between two groups of data, and the observations are due to chance
Ex. There is no difference in headache relief between individuals who take Tylenol, and those who don’t
What is an alternative hypothesis?
H1 is made after the null hypothesis
- start with H1 and continue listing H2… As many necessary for the experiment
Ex. Tylenol will allow for relief when consumed by patients with headaches
What is a hypothesis, how is it tested? (3)
- An explanation to a question
- tested by experiment or continued observation
- can be disproven, but cannot be proven true
What is a theory?
- Summarizes a group of hypotheses
What are the characteristics of a theory? (4)
- broader in scope (more data or info collected)
- new hypotheses can be generated from it
- supported by massive body of evidence
- can never become a law
What is a scientific law?
- statement of fact, usually as a mathematical formula (ex. Newton’s law of gravity)
What are characteristics of a scientific law?
- describes an observation (not “how” or “why”)
- generally accepted to be true and universal
- Basis for scientific method
What should you use in an experiment? (4)
- start with an observation and a hypothesis
- use control groups (+ and/or -) and experimental groups
What do well-designed experiments include? (5)
- independent variable
- dependent variable
- Control group (+ and/or -)
- Constants
- Number of trials (acceptable in science is 3)
What is the difference between a variable and a constant?
- A veariable is something that is changed in the experiment, while a constant is something that does not change through the experiment
What is an independent variable and what does it represent?
- The one factor that is changed by the person doing the experiment
- represents a quantity that is being manipulated in an experiment
What is a dependent variable, and what does it represent?
- The factor which is measured in the experiment
- represents a quantity whose value depends on how the independent variable is manipulated
