What do scientists do?

Learning Objectives  I will know how to ask questions and make hypotheses for scientific investigations.  I will know how to collect information by making observations.

A Well-Defined Question? We are going to Austin next week. My mom wants to see the bats. What does Austin, Texas have to do with bats? The largest urban bat colony in north America is under the Congress Street Bridge in Austin. Does the bridge cross a river or does it cross a lake?

Problems, Decisions, and New Ideas

Scientific Research and Knowledge Why is it important for scientists to only use reliable information that has been reviewed by other scientists?

Evaluate Sources Appropriate References Inappropriate References an article about cancer written by a leading oncologist a website selling skin creams

Predict and Make Hypotheses Hypothesis: If the level of water pollution increases, then the population of manatees will decrease because the plants they eat cannot live in highly polluted water.

Using Observations What do scientists do with the information they gather from their observations?  _______________ organize analyze evaluate draw conclusions share

How do scientists investigate?

Learning Objectives  I will know different methods of investigation and the steps for scientific investigations.  I will know how to ask well-defined questions for scientific investigations.

The Scientific Method I read that scientists are investigating how to make electric cars travel even farther on one charge. That would be a great improvement. Have they published any results? One model they tested costs $3.67 to recharge. It costs about 2 cents per kilometer to drive. Can you help me find out how far that electric car can travel on one charge?

Types of Scientific Investigations Name four types of scientific investigations. experiments surveys sampling models

Models What is a model?

Surveys and Sampling What tools do scientists use to conduct a survey?

Steps for Investigation Ask a question. State a hypothesis. Identify and control variables. Make a plan. Test the hypothesis. Collect, record, and interpret data. State a conclusion. Do repeated trials.

How do scientists collect and interpret data?

Learning Objectives  I will know how to select and use tools to collect and interpret data.

Data Collecting Scientists collect information over long periods of time. They use this information to make predictions.

Scientific Tools duration volume mass weight length temperature

Tools for Observing

Other Tools

Safety Scientists know they must work safely when doing experiments.

Organizing Data

Interpreting Data The __________ is found by adding the data together and then dividing by the number of data. The __________ is the value in the middle—half of the data are higher than this value and half are lower. The __________ is the value that occurs most often in the data set. The __________ is the difference between the largest and smallest values in the data set.

How do scientists support their conclusions?

Learning Objectives  I will know how to do investigations.  I will know how to analyze and interpret information and draw conclusions.

Draw Conclusions Scientists draw conclusions about what they have discovered by interpreting their data. analyze evaluate interpret infer

Observations, Opinions, and Conclusions

Evidence This scientist may be able to use his data as evidence to support his hypothesis. direct evidence indirect evidence

Review and Retest Scientists must describe exactly what they did in an experiment and how they did it.