Week 2- Tuesday Biology-
Items not considered alive:
Why do you think they are alive?Characteristics of Life:
Definition of Life:
What is the meaning of the “life”?Look at the items on the back desk. (masking tape, beenie baby, water bottle, wooden paper towel holder)Make the following chart in your journal:
Chapter 1: Exploring Life
Introduction to Biology and the Scientific
Method
Science• Science: a process
used to solve problems or answer questions about our environment; used to make decisions.
• Scientific Method: an approach taken to try to solve a problem.• Many versions are
available from very simple to very complex.
Biology• Biology: learning about different
types of living organisms•Greek ~ Bios = “life”
• Logos = “study of”• Living things do not exist in isolation
but are functioning parts in the balance or nature with biotic (living) and abiotic (non-living) things.
Biology• Biological Systems – “The whole is greater than the sum of it’s parts in Biology today!” Just understanding the parts of an organism is no longer considered sufficient we need to understand entire organisms and their relationships with each other and the biosphere at large.
7 Properties of Living Things:• 1. Order/Organization – all living
things have an orderly structure.• There are 5 – 10 million species on
our planet and all of them are unicellular (composed of one cell) or multicellular (composed of many cells).
7 Properties of Living Things:• Molecules – chemical structures composed of 2+ atoms• Chlorophyll – one of the most important molecules on Earth
because it converts light energy into chemical energy (food)• Organelles – a body in a cell that carries out a specific
function• Chloroplast – organelle in plant cells that carries out
photosynthesis• Cell – Life’s fundamental unit of structure and function
that can perform all the properties of life.• Tissue – a group of similar cells that work together with
a common purpose• Organ – multiple tissues working together to carry out a
common function
7 Properties of Living Things:• Organ Systems – a team of organs co-operating in a
specific function• Organism – an individual living thing (may be single or
multi- cellular)• Population – a group of interbreeding organisms that
are the same species in the same place at the same time• Community – all the biotic organisms in a particular area• Ecosystem – all the biotic and abiotic organisms in a
particular area• Biosphere – all the ecosystems on Earth inhabited by
life
7 Properties of Living Things:• 2. Reproduction – the production of
offspring, or a second generation, which will replace the first generation in time.• Allows for the continuation of species.• Species – a group of interbreeding individuals, or organisms, that produce fertile offspring.
Florida Tortoise Texas Tortoise California Tortoise
7 Properties of Living Things:If you cross a horse with a donkey you
create a mule (infertile offspring).Because mules are sterile we know thathorses and donkeys are not the same
species.
7 Properties of Living Things:3. Growth and Development –• All living organisms grow, or change, over time.• Growth – an increase in an organisms amount of
living material and the formation of new structures
7 Properties of Living Things:• Development – all the changes that take place in the life of an organism
7 Properties of Living Things:4. Responds/Adjusts to their Environment –• Environment – all the biotic and abiotic
surroundings to which an organism must adjust.• Air, water, weather, temperature, plants,
animals, pressure, heat, light, odor, sound, etc.•Ex. Chameleons change colors and trees
loose their leaves in the fall.
7 Properties of Living Things:• Stimulus – any condition in an environment that
requires an organism to change• Response – an organism’s reaction to a stimulus
7 Properties of Living Things:5. Evolutionary Adaptations• Adaptation – any structure, behavior, or internal
process that enables an organism to respond to stimuli and better survive its environment
• Ex. Stripes on a Zebra – Camouflage
7 Properties of Living Things:Inherited from previousGenerations
• Individuals withadaptations are morelikely to survive andreproduce. This causesthe adaptation tobecome moreprevalent in thepopulation.
7 Properties of Living Things:6. Energy Processing (obtaining, using, and releasing energy)• Energy can be used to grow, develop, repair
damage, and reproduce.• Anabolism – process of building up complex substances from simpler substances.• Ex. Building up cells or organelles orproducing sugar molecules in photosynthesis
7 Properties of Living Things:• Catabolism – process of breaking down
complex substances into smaller substances to release energy.
• Ex. Digestion and Cellular Respiration• Metabolism – all the chemical reactions
that occur in an organism.
• Anabolism + Catabolism = Metabolism
7 Properties of Living Things:• 7. Regulation:• Living things maintain a stable internal environment:• Homeostasis – an organism’s regulation of its infernal
environnent to maintain conditions suitable for survival.• • Ex. Body temperature, pH, blood pressure, or
the amount of water in a cell.
Classification of Life:• Domain (Bacteria, Archaea, and• Eukarya)• Kingdom (Plant, Animal, Fungus,• Protist, and Monera)• Phylum• Class• Order• Family• Genus• Species
Question…
If Science means “toknow” then what processdo we use to determine
what we know?
Week 2- Wednesday• List 10 observations about this picture. Make them
both qualitative and quantitative.
Scientific Method• Discovery/Descriptive Science –
relies on careful observation and analysis of data to describe natural structures or processes.
Scientific Method• The Properties of Life have emerged from complex
organisms and occasionally we have to break them down into smaller parts to understand the whole.
• Reductionalism – breaking down complex systems into simplercomponents that are more manageable to study.
Scientific Method• Systems Biology – seeks to model the dynamic behavior of wholebiological systems. It can map or predict how changes in one variableaffect other variables and the entiresystem.
• Feedback Regulation – the “output” or the “product” regulates a process
Scientific Method• Negative Feedback – the accumulation of an endproduct from a process slows the process down.
• When cells break down sugar they make ATP…when ATP levels are high cells stop breaking down sugar.• More common
• Positive Feedback – the end product speeds up to production of the end product.
• When you cut yourself platelets (Structures in your blood) aggregate (collect) where the tissues are damaged. Platelets release chemicals that attract additional platelets which will form a clot and seal the damage (scab).
Steps of the Scientific Method -• 1. Identify the Problem –•What do you want to know or explain?•Use your observations to write a question that
addresses the problem, or topic, that you want to examine.
Steps of the Scientific Method -2. Form a Hypothesis –• Hypothesis – tentative answers to well-
framed questions or your educated guess about the results of your experiment.
• If…then… logical reasoning.• Must be testable• Must be falsifiable• EX. If I increase the amount of light that plant A receives it will grow faster then plant B which receives less light.
Steps of the Scientific Method -• 3. Create an Experiment –• How will you test your hypothesis?• Develop a procedure that follows proper lab safety procedures.
Steps of the Scientific Method -• 4. Perform the Experiment –• Follow all the steps of the procedure exactly.• Data – recorded observations•Qualitative – descriptions (color, degree, etc.)•Quantitative – measureable
Steps of the Scientific Method -5. Analyze the Data –• Create data tables, charts, and graphs.• Did the experiment work the way you
expected it to?• Is there a flaw? If there is then go back
and rewrite your procedures to address the flaw. Then perform the experiment again and reanalyze your data.
Steps of the Scientific Method -6. Communicate your Results –• Write a conclusion which should include:•Summarize the experiment•Explain if and why your hypothesis was correct or incorrect.•Explain any problems you experienced and how they impacted the results.•Explain how you would improve or change this experiment.
Steps of the Scientific Method -**Remember**You can have a
successfulexperiment without
provingyour hypothesis!
Every Good Lab Should Include:•Experiment – a procedure that
tests a hypothesis
Every Good Lab Should Include:• Independent Variable – the part of an experiment that changed because it affects the outcome of the experiment.•Ex. What you change to test your hypothesis.
• Dependent Variable – the part of an experiment that results from changes in the independent variable•Ex. What you measure at the end of a lab
Every Good Lab Should Include:• Control – the part of an experiment
in which the independent variable is not applied; used to compare the results of your experiment.• Constant – the parts of an
experiment that remain the same.
Every Good Lab Should Include:• Theory – an explanation of a natural
phenomenon that is supported by a large body of scientific evidence obtained through many investigations and experiments.
• Principles – certain facts of nature that are known to be true• Ex. Gravity
Quiz 11. Define hypothesis.2. An approach taken to try to solve a problem.3. Certain facts of nature that are known to be true.4. This term describes data that is measureable.5. the part of an experiment in which the independent variable is not applied.
Lab Report FormatName, Date, Class Period in the top right hand corner of the paper.I. Title – Give it a name!II. Introduction – Summarize what youwant to know or what you want to study.III. Hypothesis – “If…then…” statementIV. Procedure – Step-by-step list (include the variables!)V. Materials - listVI. Data – Graphs, tables, & chartsVII. Conclusion – 4 questions answered (from theScientific Method notes – part 6 –Communicating your Results.)
All Good Graphs:• Have a Title• Have a labeled X and a Y axis…Remember…• DrY (Dependent Variable on the Y- axis)• mIX (Independent Variable on the X- axis)• Have numbers written in REGULAR
increments• Are drawn with a ruler• Have clearly labeled data and legends• Are colorful!
Purpose of the Scientific Process -To test hypotheses in a verifiable and credible manner
Steps of Scientific Method ObservationProblemHypothesisExperimentDataConclusion
Difference between null hypotheses and hypotheses:
Null hypothesis can be rejected—it essentially states that the variable will have no effect on the outcome of the experiment.-Ex: The color of light will have no effect on the plant’s growth rate. (null hypothesis)Blue light will cause the plant to grow at a faster rate (hypothesis)
Why scientists test null hypotheses instead of hypotheses:
-You never have enough support for a hypothesis--to say it’s the sole explanation for your results. However, with a null hypothesis you can have enough support to show it’s not the only explanation for results.
Constitutes a good scientific design:
-Repeatability-Large sample size-Simple procedure-One variable while all other factors are controlled-Clear and concise problem
Weaknesses of scientific design: -One or more of the following factors missing from above
Sample size needs to be large because:
-Helps to minimize undetected variables or variables that cannot be eliminated—precision is keyControl in an experiment is important because:-Serves as a comparison to measure against
What is the ideal number of variables:
-One
Independent variable vs. Dependent variable
-Independent variable – variable “I” change in the experiment (X-axis- graphing)-Dependent variable- variable that changes based on the independent variable (Y-axis- graphing)
Steps need to be rigid to ensure:
-consistency and reliability
Difference between inductive and deductive reasoning:
-Inductive- specific information leads to general conclusion Example: After several cakes baked in the same cake pan came out burned, Carl concluded that if he bakes a cake in that particular cake pan it will probably come out burned.-Deductive reasoning- general information leads to specific conclusionExample:The baseball coach knows the opposing batter hits fast-balls well, so she instructs her pitcher not to throw a fast-ball
Quantitative vs. Qualitative: -Quantitative- numeric data (stronger)-Qualitative- descriptive data
Best Ways to Earn Points: a. Using scientific terms correctlyb. Describing specific case examples,
and never using general referencesc. Never simply naming something,
but instead always identifying and describing something with at least a phrase or a separate descriptive sentence.
d. Being sure to give an answer that responds directly to what the question is asking.
e. Clarifying what potential essay question terms mean before you take the exam.a. Describe- Detailed verbal
picture of something—asking for just the facts, no opinions
b. Discuss- Broader than a description, conversation among different ideas or theories
c. Explain- Take something complicated or unclear and present in simpler terms
d. Compare- Focused on similarities between two things
e. Contrast- Answer emphasizing differences and distinctions