What is Biology?

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What is Biology?
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• Biology the study of life
• Bio- life
• -logy the study of
• Concepts, principles and theories that allow
  people to understand the natural world
• Biologist person who studies life

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• Essential Questions in Science
• What?
• Why?
• How?

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What do Biologist Study?

• Interactions of life
• Living things do not exist in isolation
• Living things depend on other living things as
  well as non-living things
• Interactions of the environment
• No species can exist in isolation from the
  environment around them
• Ex. If you study rabbits, you would also study
  the plants they eat and animals they prey on them
• Problems and propose solutions

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Science v. Pseudoscience

• Read the Scientific American articles Drawing
  the line between science and pseudo-science
• As you read, write notes over the distinction
  between
• Science Pseudo-science
• Also, include examples of Science and
  Pseudo-science from the article.

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Science or Pseudoscience
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Observation v. Inference

• Observation Direct method of gathering
  information in an orderly way
• Example DATA
• Qualitative descriptions of things
• Quantitative number data
• Inference Assumption based on prior experience
• The process of combining what you know with what
  you have learned to make logical conclusions

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What is an organism?

• An organism is anything that possesses all the
  characteristics of life
• Living things are organized
• Living things have structure
• All parts function together in an orderly way

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Characteristics of Life

• Organization (Cells) - Living things have
  structure
• All parts function together in an orderly way
• Reproduction making more organisms of the same
  kind
• Growth and Development living things change
  during their life
• Adaptation/Regulation responding to changes in
  the organisms surroundings
• Exchange Gases Move gases in or out of body
• (ex. CO2, O2)
• Use Energy Metabolism (release of energy from
  food)
• Excretion eliminating waste materials produced
  by the organism
• Movement all living things move (internal and
  external)

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Are viruses living things?

• Viruses are not living things.
• Viruses are complicated assemblies of molecules,
  including proteins, nucleic acids, lipids, and
  carbohydrates.
• On their own they can do nothing until they enter
  a living cell. Without cells, viruses would not
  be able to multiply.
• So how do viruses work?

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Levels of Organization
Animation link
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Atom
The atom is a basic unit of matter that consists
of a dense central nucleus surrounded by a cloud
of negatively charged electrons.
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Molecule

• A group of two or more atoms held together by
  chemical bonds

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Organelle
An organelle is a specialized subunit within a
cell that has a specific function, and is usually
separately enclosed within its own lipid
bilayer. The name organelle comes from the idea
that these structures are to cells what an organ
is to the body.
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Cell

• The cell is the basic structural and functional
  unit of all known living organisms.
• It is the smallest unit of life that is
  classified as a living thing.
• Is often called the building block of life

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Tissue

• A group of biological cells that perform a
  similar function

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Organ

• A collection of tissues joined in a structural
  unit to serve a common function

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Organ System

• a group of organs that work together to perform a
  certain task. Examples circulatory system, the
  respiratory system, the nervous system, etc.

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Organism

• Single individual

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Population

• Group of organisms of same species that
  interbreed and live in the same place at the same
  time
• Compete for resources

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Community

• Many interacting populations
• Change in one population causes changes in the
  others

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Ecosystem

• Interacting populations and the abiotic factors
• Types Terrestrial
• Freshwater
• Saltwater

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Biosphere

• The portion of the earth that supports life

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• How do we answer questions about life?
• We use the Scientific Method
• Set of organized steps that help us answer
  questions about observations that we make

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Steps of the Scientific Method

• Observation
• Research
• Hypothesis
• Procedures
• Experiment
• Organize Data
• Make Conclusion
• Share Results

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Observation

• Use your 5(4) senses to notice things around you
• See an organism change color
• Hear an organism make a sound
• Feel the texture on an organism
• Smell an odor
• Taste Never taste anything in lab!!!
• Develop a question based on your observations

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Research

• Find out as much as you can about what you
  observed
• Look it up!
• Computer
• Books
• Journals
• Talk to experts in the field
• Newspaper
• TV
• Prior knowledge

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Hypothesis

• Make an educated guess
• I stress the word educated
• Your hypothesis is a guess, but it is a guess
  based on information that you have learned from
  your research
• I hypothesize that..

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Procedures

• Write the steps you will use to test your
  hypothesis
• First I will .
• Then I will .
• After that, ..
• Next, .
• Finally, .

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Experiment

• Test your hypothesis using the procedures you
  have written\
• When you experiment
• Follow procedures closely
• Follow safety rules
• Make observations
• Record data collected

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Organize Data

• Try to make sense out of the data you collected
  and organize it in a way that tells a story
• Make charts, graphs or tables
• Look for trends in your data

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Make a Conclusion

• Determine what your data is telling you.
• Does your data help to confirm or disprove your
  hypothesis?
• Does your data answer your initial question?
• What does it mean?

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Share Your Results

• If you dont share what you found how will anyone
  know?
• It is important for scientist to let others know
  what they have discovered.
• Scientist usually publish their research in
  scientific journals
• When scientist publish their research they use a
  specific format. All scientific journals use the
  same format

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What are you doing Friday Night?

• Use the Scientific Method to go through the steps
  you would use to figure out what you will do this
  Friday night.
• Observation what is there to do???
• Research find out!
• Hypothesis what do you think will happen?
• Procedures how will you go about it?
• Experiment the actual activity
• Organize Data What happened
• Make Conclusion Ok, so how did it go?
• Share Results You know you will tell all your
  friends about it

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Experimental Variables

• When you do an experiment you should always be
  aware of your variables
• There are three types
• Independent Variables
• Dependent Variables
• Controlled Variables

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Independent Variables

• The condition in the experiment that is changed
• By changing the independent variable, a scientist
  can observe or measure the effects of the change
• Ex. Growing plants
• You want to determine the effect of water on the
  growth of a plant, in that case, your independent
  variable would be water.

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Dependent Variables

• Any change that results from the manipulation of
  the independent variable
• Its the thing you measure or collect data on
• Ex. Growing plants
• When you change the amount of water that you
  give the plants (independent variable), the
  growth of the plant slows down. The dependent
  variable is the height of the plant or the number
  of flowers that the plant produces

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Controlled Variables

• Also referred to as a Constant
• The standard, the parts of the experiment that
  are kept the same.
• Ex. Growing plants
• You change the amount of water you give the
  plants (independent variable), but you keep
  everything else the same, like amount and type of
  soil, and fertilizer, amount of sunlight,
  temperature.

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Experimental Design

• Experimental Group
• The group that receives the change
• Control Group
• The group that remains the same. The original
  condition

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Replication in Experiments

• You cant determine the effect of less water on a
  plant if you have only one plant.
• You must replicate
• More is always better!

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What happens when many people come up with the
same results?

• Theory
• After a hypothesis has been tested and the same
  results are obtained many times by many people, a
  hypothesis may become a theory.
• Law
• After a theory has been tested and the same
  results are obtained many, many, many times by
  many, many, many people, a theory may become a
  law.