biology - unit one

1 meter = _____ decimeters

10 decimeters

scientific notation

A method of writing or displaying numbers in terms of a decimal number between 1 and 10 multiplied by a power of 10.

Scientific Method

A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.

scientific method: hypothesis

A statement that can be tested as a possible explanation for a set of observations Normally in the format of "if this, then that, because..." Cause - effect - rationale

scientific method: experiment

A test for the hypothesis performed under controlled conditions

scientific method: data collection and analysis

Accurate recordings of data in an organized manner Includes tables, graphs, etc.

scientific method: conclusion

An interpretation and summary of the results of an experiment based on the collected data

1. Which statement best describes a hypothesis? A.The facts collected from an experiment are written in the form of a hypothesis B.A hypothesis is the correct answer to a scientific question C.A hypothesis is a possible, testable explanation for a scientific question D.A hypothesis is the process of making careful observations

C

Which of the following examples show the correct form for scientific notation? A. 75.15 B. 7.515 X 1^5 C. 7.515 X 10^5 D. 75.15 X 10^5

C

Which part of experimental design is essential to ensure that results are accurate and valid before moving on to analysis? A. Independent variable B. Dependent variable C. Repeated trials D. Control

C

metric system: temperature

Celsius

When converting from scientific notation to real, which answer is correct for this notation: 9.421 X 10^-3 A.0.0009421 B. 9,421 C. 942.1 D. 0.009421

D

controlled experiments: examples

Example 1 A zoologist wants to know if feeding mice a vitamin supplement will make them grow larger. She feeds the five mice their regular food, and she feeds five other mice food with vitamins. She measures the weight of the mice at the start and end of the experiment. Example Two A student is interested in the effect of the temperature of water in her aquarium on the activity level of her fish. She divides her aquarium water and fish into three aquariums, one that is maintained at room temperature (about 70 F), one that is heated to 80 F, and one that is cooled to 60 F. At 6 PM each day, she watched the fish for 30 minutes and records her observations about their activity. The student in the last example is also curious about which kind of fish food will make her fish the most active. She decides to test fish food type in the experiment described above. Explain why this is not a good idea.

experimental design

Experimental design refers to how participants are allocated to the different conditions (or IV groups) in an experiment.

Alysha wants to test the effect of different materials on the melting rate of ice. She finds the initial mass of four pieces of ice. She then covers three pieces with either tinfoil, plastic wrap, or paper. The fourth piece is left uncovered. After 30 minutes, Alysha calculates the final mass of each piece of ice to determine which melted the fastest. What are the independent and dependent variables in Alysha's experiment?

In the experiment conducted by Alisha to test the effect of different materials on the melting rate of ice, the dependent variable is the mass of the ice, and the independent variable is the type of cover material. Explanation: During an investigation or experiment, the dependent variable is the one whose changes will be studied, while the independent variable is able to influence the changes of the dependent variable. In the case where it is wanted to measure how different cover materials affect the rate of ice melting, the dependent variable is the mass of ice and the independent variable is the coverage material, capable of affecting the time it takes for the ice to melt.

experimental design: repeated trials

Performing the experiment numerous times or having many trials run simultaneously to verify results More trials = more evidence = more valid results

Poison ivy is a weed that produces an oil which causes skin rashes. Scientists want to perform an experiment to see if poison ivy grows taller when exposed to more carbon dioxide. How should the control group in this experiment be treated?

Poison ivy is a weed that produces an oil which causes skin rashes. Scientists want to perform an experiment to see if poison ivy grows taller when exposed to more carbon dioxide. The control group in this experiment should be be treated as : The control group should have plants growing at normal carbon dioxide level.

scientific method: research

Searching, collecting, and studying information from a variety of sources

scientific method: problem

Some questions about the world and the occurrences in it A topic we don't understand or want to know more about

experimental design: control

The factor that is used as the standard to which everything is compared Remains close to "normal" or untested conditions

experimental design: dependent variable

The factor that responds or depends upon the independent variable This variable depends on how the experiment is set-up

experimental design: independent variable

The one and only factor that is changed or varied by the experimenter in an experiment Remember that being independent means you're able to function on your own without outside influence

scientific method: observation

Using all of the senses to identify and study a problem Awareness of the world around us and a curiosity to understand how it works

standard notation format

a * 10 ^b, a = any number greater than or equal to 1 but less than 10, b = integer

Accuracy vs. Precision

accuracy: how close experimental value is to accepted value; precision: how closely measured values agree with each other

metric system: mass

gram (g)

metric system: volume

liter (L)

In the metric system, the basic unit of mass is the:

meter

metric system: length

meter (m)

What does the abbreviation "mg" stand for?

miligram

metric units: least to greatest

milli, centi, deci, deca, hecto, kilo

Steps of the Scientific Method

observation, problem, research, hypothesis, experiment ( independent variable, dependent variable, control, contestants, repeated trials), data collection and analysis, conclusion

metric system: time

seconds (s), minutes, hours

Cubit

the distance from the point of the elbow to the tip of the middle finger

Span

the distance from the tip of the thumb to the tip of the little finger with the fingers spread apart

Digit

the width of the index finger or middle finger

Palm

with of four fingers held together

experimental design: constants

¡Factors that remain the same during an experiment ¡This helps keep the experiment controlled and the results from being skewed