What is Life? & Scientific method

Ask a Question https://www.youtube.com/watch?v=SMGRe824kak

Ask a question?? What do you want to know? Write it as a question Be specific

How to Write a Testable Question Tamara Helfer, 2012 Sequoia Science Explorations

What is a “Testable Question?” A testable question is one that can be answered by designing and conducting an experiment. Testable questions are always about changing one thing to see what the affect is on another thing

Sample Testable Question Does changing the height of the ramp affect the speed of car going down the ramp?

Testable Question Formats Does changing _______ affect _______? How does changing _____ affect _____? If I change ______, will it affect ______? Now your turn to write a testable question

EXIT TICKET Write one testable question ABOUT ANYTHING! What makes this question testable?

Research the topic

Observe-use all 5 senses

Observation- Qualitative observation- descriptions that can be observed but not measured Examples- Colors, textures, smells, tastes, appearance, beauty, etc Quantitative observation- an observation dealing with numbers that can be measured Examples: Length, height, area, volume, weight, speed, time, temperature, humidity, sound levels, cost, members, ages, etc.

Qualitative or Quantitative? The chemical reaction released 10 joules of heat into the environment. Chemical A and chemical B reacted creating bubbles. The beaker contained 10 mL less water that the previous day. The brown rock is heavier than the black rock. The bear has a number 3 shaved into its fur.

Inference Logical assumption based on facts “something is burning”

Observation-qualitative

Observation-quantitative

3 APPLEs

Observations: People wearing helmets Two people in green and white One person in in black One person wear stripes Persons arms out like a T with a football in hand Persons arms above their head

Inference- an interpretation of one or more observations. Inferences: The playier in black scored a touchdown #81 is tackling the player in black

A

B

C

Form a hypothesis An “educated guess”-a possible answer to the question….

Experiment A process where you gather information Must include of materials Cannot ASSUME that a person knows a step.

Design an experiment A good experiment will have: Independent variable-the scientist changes it— YOU do the changing!!!! Dependent variable-factor that is expected to change due to the independent variable Constants-Factors that remain the same. Control- Does not receive the test variable, is compared to the experimental group

Independent variable Examples-time, temperature and distance X-axis

Dependent variable On the Y- axis Is dependent on the changes in the independent variable. Examples: How high does it grow? How long did it take? How far did it travel? Y axis X axis

Constant Examples:Temparture, location SAME for each experiment- DO NOT CHANGE!!!!!!!!!!!

Control Sample that is treated like the other experimental groups except that the independent variable is not applied to it . -Source of expected results -Provide a comparison group What “normally” you would expect….

Collect Data Show data NEATLY in charts or graphs

Draw a conclusion What were the results of your experiment? This is the part you tell your results.

Communicate results Prove or disprove hypothesis Theory Law

Theory A well tested idea that explains and connects a wide range of observations. Over time these can CHANGE!!!!!!!

Law What scientists expect to happen every time under a particular set of conditions. DO NOT CHANGE!!! Example:Law of Gravity

What defines life?

Movement All living things have the ability to move through internal and external structures. Example: walking, plants move to track sunlight Earthworm use circular and longitudinal muscles to move through soil

Reproduction The production of offspring 1. Sexual reproduction- 2 cells from different individuals unite to form a new cell 2. Asexual reporudction-1 cell divides to form 2 INDENTICAL cells Earthworms have both sperm and eggs within their bodies but they cannot self-fertilize and need to mate with another individual. After mating, a cocoon containing the fertilized eggs is deposited in the soil.

Sensitivity Living things respond to their environment Homeostasis-keep conditions suitable for life Earthworms have light-sensitive cells scattered in their outer skin. Their skin cells are also sensitive to touch and chemicals.

Growth All living things have the ability to mature and age over time Earthworms hatch from eggs and can grow up to a metre or more in length! Some earthworms are also able to regrow small parts of their body that have been lost or injured.

Respiration Organisms have the ability to exchange gases between their body and the environment The food that earthworms eat supplies their body with energy-rich molecules such as glucose. On entering the cells of their body, these molecules are broken down in a series of steps to release energy to be used by the body, producing carbon dioxide and water as waste products.

Energy Living things must be able to create energy as a cell and a whole organism

Excretion Waste products must be removed from an organism after nutrients have been obtained. Earthworms excrete waste from the last segment of their body.

Nutrition Living things must be able to ingest nutrients from their environment Earthworm nutrition comes from a variety of sources, depending on their species. Food types include manure, compost, plant material, fungi, microorganisms and decaying animals. They take in food through their mouths.

"What do all living things have in common?" Movement-all living things have the ability to move Reproduction-produce offspring Sensitivity-respond to their environment Growth- ability to mature and age through time Respiration-ability to exchange gases Energy-ability to create energy as a cell and whole organism Excretion- ability to remove waste products Nutrition- able to ingest nutrients fro their environment