Chapter 1: The Study of Life

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Chapter 1 The Study of Life

• Section 1.1 The Study of Life
• Section 1.2 Unifying Themes of Biology
• Section 1.3 Scientific Thinking and Processes

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I. What is Biology?
Biology The study of all living and once
living things If you break it down Bio
means Life logy means the study
of Biologist A person who studies living
and once living things
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Earth is home to an incredible diversity of life

• Biosphere
• - Bio Life
• - sphere circle
• Biosphere Earth
• It is where all living things and all the places
  they are found.
• Includes environments (ecosystems) such as
  deserts, grasslands, forests, saltwater and
  freshwater, etc.

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• Biodiversity Video
• Biodiversity
• - Bio life
• - diversity variety/differences
• Biodiversity all the variety of life across the
  biosphere. Why is biodiversity greater closer to
  the equator?
• Species is a particular type of living organism
  that can reproduce by interbreeding among
  themselves to produce fertile offspring.
• Approximately 10,000 species discovered a year.
• Approximately 50,000 species become extinct every
  year.

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Characteristics of Life - Video

• What does it mean to be living?
• - To be considered LIVING, ALL Characteristics
  of Life must be met.
• - Organism is any individual living thing.
• 1. All living organisms are made of CELLS
• The cell is the basic unit (building blocks) of
  structure and function in all living things
  (life)
• Some organisms are unicellular - one-celled (all
  bacteria)
• Some are multicellular - made of many cells
• Intro to cells video

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2. Need for Energy Living organisms need a
source of chemical energy.
Characteristics of Life

• - Three ways an organism obtains food
• Consumers (Animals) that rely on other
  organisms for food.
• Producers (plants) make or produce their own
  food through photosynthesis.
• Decomposers (bacteria, fungi) Break down items
  by releasing digestive enzymes onto it.
• Energy is important for metabolism!
• Metabolism all the chemical processes in the
• the body that build up or break down
• materials.

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Characteristics of Life

• 3. Living organisms RESPOND TO THE ENVIRONMENT
• Organisms must react to a stimulus (stimuli) in
  their environment in order to survive.
• A stimulus causes a reaction.
• Physical light, temperature and touch.
• Reaction video

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Characteristics of Life

• 4. Reproduction and Development
• - Reproduction - A process of creating
  offspring (new individuals of same species).

Includes the passing of genetic material, DNA,
from parent to offspring. DNA
Deoxyribonucleic Acid
This is Important for the
survival of a species.
There are 2 types of reproduction.
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TWO TYPES of REPRODUCTION

• A. Sexual Reproduction
• Formation of a new organism by the
  union of 2 reproductive cells
  (sperm and egg)
• The offspring will be genetically
  different from the parents.
• B. Asexual Reproduction video
• Formation of a new organism from only 1 cell
• Offspring will be genetically identical to the
  parent cell.
• Example a bacterial cell dividing into two
  identical cells.

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Characteristics of Life

• - Development
• Organisms grow in size (length and width) using
  materials and energy from the environment
• As a living organism grows body structures
  develop and change.
• Examples
• Adolescents change into adults (puberty)
• Maggot develops into a fly
• Caterpillar develops into a butterfly
• Tadpole develops into a frog

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http//biology.kenyon.edu/fennessy/AMN20Wetland2
0Webpage/Comps20Webpage/usingamphibiansasindicato
rsofwetlandintegrity.htm
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II. Unifying Themes of Biology

• 1. All levels of life have systems of related
  parts.
• - System is an organized group of related
  parts
• that interact to form a whole.
• - Examples
• - Ecosystem
• Eco environment
• System related parts
• - Ecosystem all the living and nonliving parts
  interacting with one another.
• - Ecosystem video

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Unifying Themes of Biology

• 2. Structure and Function are related.
• - What something does (function) in an
• organism is directly related to its shape or
  
• form (structure).
• - List five cell examples below
• Structure Function

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Unifying Themes of Biology

• 3.Maintaining Homeostasis in order to survive in
  diverse environments.
• - Homeostasis
• - Homeo constant/remains the same
• - stasis stable
• - Homeostasis maintaining a constant internal
• condition with changing environmental
  conditions.
• - Examples
• - Body temperature and outside
  temperature
• - Shiver when cold
• - Sweat when hot
• - thirsty when you need water.
• - Blood sugar (glucose/insulin)
• Video (girl) Homeostasis reaction video

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Unifying Themes of Biology

• 4. Evolution explains the unity and diversity of
  life
• - Unity how things are the same
• - Diversity how they are different
• - Two organisms can be very different like a
  human and bacteria but can share similar cell
  characteristics.
• - Evolution a change over a long period
  of time.
• - One way evolution occurs is through
  adaptations.
• - Adaptation - a trait that makes a
  living
• organism better able to survive.
• Evolution Video

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1.3 Scientific method A series of steps used to
solve a problem

• Make an observation
• - Use your senses to record data and study the
  world.
• - Observations can recorded as data.
• 1. Qualitative data - include descriptions
  such
• as sights, sounds, touch, taste
  and smells.
• 2. Quantitative data can be measured or
• counted such as mass, volume, temperature.

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Scientific method A series of steps used to
solve a problem

• 2. Form a hypothesis- Based on your observations
  and data research, what do you think will happen?
  Or what could be a possible explanation?
• - A hypothesis is a proposed answer for a
• scientific question that can be tested.
• - Always written as an if then
  because sentence.
• - If I place ice in boiling water then
  the ice will melt because heat causes the
  molecules to move faster.
• - When data does not support a hypothesis, it
  is rejected.

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Scientific method

• Conduct a controlled experiment
• - Testing the hypothesis using a
  step-by-step procedure.
• - A controlled experiments tests 1 variable at a
  time.
• 1. An independent variable - a condition
  that is changed or manipulated by a scientist.
• - What you are testing.
• 2. A dependent variable what you are
  observing and measuring during the
  experiment.
• - Everything in a controlled
  experiment remains
• constant (the same) except for one thing
  that you change.

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Scientific method

• 3. Controlled experiment continued
• - A controlled experiment needs to have 2
  groups.
• 1. The experimental group receives the
  independent variable.
• 2. The control group is used for
  comparison to the experimental group.

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Scientific method

• 4. Analyze the Data Interpret the recorded
  results of the experiment in order to make a
  conclusion.
• 5. Draw a conclusion Evaluate the results.
• - A conclusion should address the following
• Was the hypothesis correct?
• How does the data support your conclusion?
• Were there errors that might have changed the
  results?
• How might those errors be avoided next time?

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SCIENTIFIC METHOD CONTINUED

• - Experiments should be repeated many times
  to check the results for consistency.
• If the results are not the same then a new
  hypothesis needs to be made.
• A hypothesis can become a theory if it is tested
  over and over again and is supported with a wide
  range of evidence.
• A theory can be used to predict the outcome of
  other events.
• Theories are not proven to be true.
• Theories can change based on new evidence.
• Are supported by a wide range of evidence.

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SCIENTIFIC METHOD CONTINUED