What characteristics do living creatures have in common? Properties of Life What characteristics do living creatures have in common?

Living creatures are ORGANIZED All made of the same collection of chemicals, but we are organized as… molecules proteins, fats, carbohydrates, nucleic acids carbohydrates proteins DNA

Living creatures are ORGANIZED All made of the same collection of chemicals, but we are organized as… organelles & cells plant cells & animal cells plant cell animal cell

Living creatures are ORGANIZED All made of the same collection of chemicals, but we are organized as… organs & organ systems respiratory, circulatory, digestive, etc.

Living creatures RESPOND Respond to internal changes Homeostasis maintaining balanced conditions inside the body Respond to external changes

Living creatures use ENERGY Metabolism all the reactions your body performs to make & use energy eating & digestion & elimination of waste synthesis = building cellular respiration = making energy mitochondria

Living creatures GROW & DEVELOP Change over an individual’s life time get bigger mature so they can reproduce

Living creatures REPRODUCE Make the next generation

…It’s how we think about the world around us… Scientific Method… …It’s how we think about the world around us…

Scientific Method is… An organized approach to asking questions and making discoveries. The way that scientists (and many non-scientists) think about problems that they encounter.

Scientific Method:  Observation  Problem  Hypothesis  Experiment  Data  Conclusion  Theory

Information gathered using the five senses or tools Observations: Information gathered using the five senses or tools

A question one might ask based on the observations that are made. Problem: A question one might ask based on the observations that are made.

Hypothesis A possible explanation of the problem that we wish to test. (it doesn’t have to be correct!!) Many hypotheses can be made – they predict the outcome of an experiment.

An organized test of a hypothesis. Experiment An organized test of a hypothesis. This video shows an impact experiment of a high-speed impact into a frozen comet-like material (dust, ice, window cleaner and Worchestershire sauce) over a highly porous target (garden perlite). The impact makes a small hole in the comet, simulating a strength-controlled crater, but a large crater grows below and peals back the surface crust like petals of a flower. The result is similar to a deeply buried explosion. Credit: NASA

The results of experiments. Data The results of experiments. Data can be expressed as numbers or descriptions. Example: the elephant is 3 meters tall.

Conclusion What has been learned from the experiment. Conclusions are supported by data.

Example: The theory of gravity A broad explanation of natural events that is strongly supported by a body of evidence - time tested by many people. Example: The theory of gravity

Some other scientific method terms… Inference – a possible explanation based on an observation. Opinion – What someone thinks about something. We try to keep this out of science!

Some other scientific method terms… Control – What we compare our data against. (usually helps to show what we already know)

Some other scientific method terms… Variable – that which is manipulated in an experiment to get a result.

Some other scientific method terms… Independent Variable – When this changes, it results in change in the other variable. Dependent Variable - That which changes as a result of a change in the ind. Variable.

Validity: A good experiment should…. Be easily repeatable. Have a large sample size Control for as many variables as possible.

Showing patterns & trends Graphing Your Data Showing patterns & trends A picture is worth a thousand words!

Types of data (information) Variables what you measure in an experiment dependent variable measured variable unpredictable change: we don’t know how it will change until we do the experiment Y-axis independent variable manipulated variable predictable change: it only changes because we chose how it would change X-axis The effect of _____________ on _____________ INDEPENDENT DEPENDENT

Examples of experiments 1 How does fertilizer affect the growth rate of plants? we set up an experiment testing different amounts of fertilizer on different plants & measuring the growth (height) of the plants: dependent variable (Y-axis)? height of plants independent variable (X-axis)? amount of fertilizer The effect of _____________ on _____________ Amount of Fertilizer Height of Plants

Examples of experiments 2 How does exercise affect heart rate of 10th grade student? we set up an experiment testing different lengths of time of exercise (minutes) on the heart rate of students: dependent variable (Y-axis)? heart rate independent variable (X-axis)? minutes of exercise The effect of _____________ on _____________ Exercise Heart Rate

Examples of experiments 3 What’s the favorite drink of students? we set up an experiment surveying students and asking which is their favorite drink : dependent variable (Y-axis)? number of students independent variable (X-axis)? type of drink The effect of _____________ on _____________ Type of Drink How many students chose it

Making pictures out of data How’s a critter to choose? Graphs line graphs graphing data that shows continuous change bar graphs (or histograms) graphing data that is in disconnected groups

elevation (feet above sea level) How does elevation affect temperature? Line graph! elevation (feet above sea level) temp. (°C) 30 500 25 1000 20 1500 15 2000 10 2500 5 30 1200 ft? 25 20 18 temperature 15 10 5 500 1000 1200 1500 2000 2500 elevation 30

Which drink do you like best? number Coke 1 Pepsi Water 4 Iced tea Gatorade 3 6 Bar graph! 5 4 number of students 3 2 1 Coke Pepsi water tea Gatorade type of drink 31

Lab Report Template name and date Title: Descriptive title explaining the purpose of the experiment. Purpose: The question being answered in the experiment.

Lab Report Template Hypothesis: What you believe will happen, in the form of an “If, then” statement.

Lab Report Template Materials: List all materials used in the lab Procedure: List step by step how to complete the lab Data: Independent and Dependent variable listed

Lab Report Template Analysis: At least a paragraph that explains what your data shows Conclusion: Ties lab together. Is hypothesis supported or refuted? Include any suggestions for improving the experiment. What could have been a source of error and give a suggestion for further research.