Ecology (ecosystems/biomes, producers/consumers/decomposers, food chains, and major kingdoms) all studies during the Earth/Space Science year at Heartlife.
Where did I get these numbers? Are they estimates or is there data to back them up? Some articles/PPTs I looked at estimated over 100 million diff. species. -- These are all questions you should ask whenever you hear facts presented. Who is this nebulous "SCIENTISTS" authority that is so often cited? My source for this slide: http://www.livescience.com/4593-greatest-mysteries-species-exist-earth.html
...or unrecognized variable (maybe two different animals made tracks on top of each other - they'd be hard to distinguish)? ...or no control (you couldn't tell what's causing a change)
Example: does amount of sunlight affect a plant's growth?
NOT theory becomes law becomes fact
Intro to Life Science & Biology
Welcome to Biology & Life Science Heartlife 2012-2013 Teacher: Julie Pen Science is Organized Knowledge
Biology - The Study of Life• Greek prefix bio = "life"• Greek suffix logy = "the study of" • What well study this year: – The Scientific Method – Cells: structure, function and metabolism – Cell division, DNA and RNA, Genetics – Geology and Evolution – Human Systems: • Skin - Muscles - Bones • Human Nutrition and the Digestive System • Circulatory & Respiratory Systems • Nervous System and Endocrine System
Life on Planet Earth• 5 - 10 million different species currently exist on Earth• Less than 2 million identified/classified by scientists – most undiscovered species are tiny or microscopic – taxonomy (observing, sorting, naming and describing) helps scientists understand how living things work and affect the world around them, including us! • OBSERVATION – info-gathering – question • HYPOTHESIS • EXPERIMENT – materials & procedures – data collection • CONCLUSION
Hierarchy of Life - zooming out• Organism – an individual living thing• Population – a group of organisms (of the same species) living in a certain area• Community – a group of interdependent organisms (different species) inhabiting the same region and interacting with each other• Ecosystem – all the organisms that live in a particular place, together with their nonliving physical environment (air, sun, rocks, etc.)• Biosphere – all the ecosystems of our planet living on earth’s crust, within its waters and throughout the atmosphere
Hierarchy of Life - zooming in• Organism – an individual living thing that can function independently• Organ systems – groups of organs that work together to perform a specific function (i.e. skeletal, respiratory, or nervous systems)• Organs – structures made of different tissues that all work together for a specialized purpose (i.e. heart, kidney, brain, femur)• Tissues – groups of similar cells that perform a particular function (i.e. muscle tissue)• Cells – basic structural and functional unit of all organisms• Molecules – two or more atoms bonded together• Atoms – the basic unit of all matter
Hierarchy of Life • Atom • Molecule • Cell s ye ar Thi • Tissue • Organ • System • Organism • Population ar • Community t ye Nex • Ecosystem • Biosphere
Lab Safety• Science labs can be dangerous - how can we keep it safe? – Read, listen, and follow directions carefully. – NO gum, food or drinks during lab time. – Proper attire (shoes, hair, protective items). • Goggles, labs coats & gloves will be provided. – Eyewash sink (for skin/spills, too). – Fumes. – Clean-up (proper disposal). • *NOT down the drain*
The Scientific Method - Observation• It starts with an OBSERVATION: – youre on a hike with your classmates and you notice a footprint – you wonder, "What type of creature made this track?" – youre hiking near a stream, so its likely some sort of aquatic bird or mammal – looking closely at the track, you see there are 5 digits (toes or claws) which rules out birds, and the left and right limbs seem to be roughly 10 cm apart. background research
• You snap a picture of the tracks (with your foot in the shot for size reference) and head home • After a quick internet search for "aquatic mammal tracks," you find these pictures:Otter Bullfrog Lizard Turtle Alligator
The Scientific Method - Hypothesis• Based on the information youve gathered, what HYPOTHESIS would you make? – The tracks found near the stream on our hike were made by... » An Otter » A Lizard » A Turtle » A Bullfrog » An Alligator
The Scientific Method - Experiment• How are you going to TEST your hypothesis?• You need to design an EXPERIMENT • A good experiment always has: – Variables • parts of your experiment that will change • usually just one thing changes at a time – Controls • parts of experiment that will stay the same every time • gives you something to compare the changes to • What happens if there is more than one variable?• Three aspects of an experiment: • Materials, Procedures, and Data Collection
Experiment Procedures• To perform an experiment, you need written procedures. Why? – to record EXACTLY what you did • detailed, step-by-step instructions – so it can be repeated (by you or others) 1. Measure imprints to nearest millimeter • size of digits, length & width • entire foot, length & width • distance between prints, length & width 2. Measure actual prints of hypothesized animal • compare measurements and record differences 3. Obtain cast of viewed prints • follow procedures at http://www.bear-tracker.com/plastertracks.html Cast 4. Obtain mold of hypothesized animals foot • follow 3D casting kit procedures • See if cast fits into mold and note any differences.Mold
Experiment Materials• There are usually supplies needed, listed in the materials section of the experiment. 1. Lab notebook and writing instrument 2. Metric ruler 3. Gypsum plaster and water 4. Cardboard strip and paper clip 5. Containers for mixing (margarine tubs or food cartons) 6. Wooden popsicle stick 7. Alginate molding powder
Experiment Data Collection• As you perform the experiment, observations and data will be recorded. – measurements listed in a chart – written observations – drawings Imprint Measurements (in mm) – photos #1 (L) #1 (L) #2 toe #2 toe #3 toe #3 toe #4 toe #4 toe #5 toe #5 toe toe length toe width length width length width length width length width 8 mm 4 mm 9 mm 4 mm 11 mm 5 mm 11 mm 4 mm 10 mm 4 mm Entire print length: 35 mm Entire print width: 30 mm Length between prints: 97 mm Width between prints: 132 mm Hypothesized Animal Measurements #1 (L) #1 (L) #2 toe #2 toe #3 toe #3 toe #4 toe #4 toe #5 toe #5 toe toe length toe width length width length width length width length width Entire print length: Entire print width: Length between prints: Width between prints:
The Scientific Method - Conclusion• After analyzing your data, you form a CONCLUSION – The measurements, when compared, showed an average 1.4 mm difference in length and .7 mm difference in width. – The cast was almost identical in shape, but did not fit into the mold of the hypothesized animal because it was 7 mm smaller in width and 4 mm shorter. – This supports the hypothesis that the animal tracks were made by...
The Scientific Method • If hypothesis is supported – repeat to verify results – share findings and let others perform the experiment• If hypothesis is rejected – modify and repeat• Either way, something was learned! – NEVER make up results simply because you think it was “supposed” to go differently
State the Problem (as a ?)Observation Do Background ResearchHypothesis "Best Guess" Solution Revise! Try Again Design (Materials & Procedures)Experiment Perform (Collect & Analyze Data)Conclusion Hypothesis is True Hypothesis is False or Partly True Report Results
Lab NotebooksAlways include:• date the experiment is performed• names of your lab partnersOBSERVATION: The Problem: in the form of a question. Background research: what you already know or have learned.HYPOTHESIS: what you think will happen.EXPERIMENT: Materials: a list of the needed equipment and materials. Procedures: step-by-Step instructions to perform the experiment. Data: measurable results (written observations, lists, charts, graphs, labeled diagrams, etc.) CONCLUSION: how your data relates to your hypothesis.
Bias in Scientific Research• Hypothesizing requires speculation – bias is an assumed belief that affect the way you see and understand things – bias is always present when formulating a hypothesis • The Scientific Method forces only the facts to be considered – seeks to eliminate variables that can skew results – encourages collaboration & accountability • shared results, repeated studies – still, bias is ALWAYS present & affects research outcomes
Fact - Theory - Law• Fact: – an objective, verifiable observation of something that occurs in our natural world – i.e. gravity, natural selection, heat exchange• Theory: – an explanation of how natural occurrences work • it can be observed, repeated, and tested with predictable results • a hypothesis that is proven correct often explains part of theory – i.e. Theory of Gravity, Theory of Evolution, Kinetic Theory of Matter• Law: – a mathematical description of observable phenomenon – i.e. Newtons First Law of Universal Gravitation F = Gm1m2 r2