Biology Ch. 1

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Biology Ch. 1

• Biology The Study of Life

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• Biology - the study of living things
• Organism
• - an individual living thing
• - has all the characteristics of life

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Characteristics of living things

• 1. Organization

Cellular
Nerve Cell
Organelle
Nucleus
Chloroplast
Mitochondrion
Molecular
DNA
Glucose
Water
Atomic
Nitrogen
Carbon
Hydrogen
Oxygen
Subatomic
Electron
Neutron
Proton
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• 1. Organization

PronghornAntelope
Organism
Organ System
NervousSystem
Organ
Brain
Tissue
Nervous Tissue
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1. Organization

• - Made up of Cells
• - unicellular vs. multicellular

Leaf tissue
Paramecium and Didinium
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2. Reproduction

• - asexual vs. sexual

Click on picture
E. coli showing binary fission
Human egg and sperm
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2. Reproduction

• Asexual or sexual?

1 cell splitting into 2 cells
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2. Reproduction

• Asexual or sexual?

Beetle pollinating a flower
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2. Reproduction

• Asexual or sexual?

Hydra budding
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2. Reproduction

• Asexual or sexual?

Earthworms Mating
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2. Reproduction

• Asexual or sexual?

Sheep clones
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3. Growth and Development

• 1. growth
• - increase in size or number of cells

Click on picture
Sea Urchin Early Embryonic Development
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3. Growth and Development

• 2. development
• - increase in complexity

Common Whelk
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4. Response to Environment
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4. Response to Environment
Homeostasis

• maintaining a constant internal environment
• - necessary for life

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5. Obtain and Use Energy

• 1. autotrophs

- make their own food
2. heterotrophs
- get food from other organisms
Cycad photosynthesizing
Praying Mantis eating a Grasshopper
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6. Evolution

• - gradual accumulation of useful adaptations over
  time

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III. The Scientific Method

• - organized common sense
• A. Observe and State a Problem
• B. Form a Hypothesis
• - possible explanation

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C. Test the Hypothesis (Experiment)

• - tests a hypothesis under controlled
  conditions
• 1. Experimental (independent) variable
• - the single variable being tested

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2. Response (dependent) variable

• - measured or observed variable that changes
  as a result of the experimental variable

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3. Control Setup

• - part of the experiment that doesnt
  receive the experimental variable
• - serves as a basis for comparison

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D. Record and Analyze Data

• - descriptive vs. numerical information
• - metric system (universal)
• E. Form a Conclusion
• - Does the data support the hypothesis?

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F. Peer Review and Publication of Findings

• - experimental findings are scrutinized for
  errors by other scientists
• - verified scientific research is published in
  professional journals

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G. What is a Theory?

• - explanation that is continually supported by
  evidence