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Chapter 1- The Scientific Study of Life 

Biology is the scientific study of life and it includes all forms of life

All organisms are made of cells. Cells are the basic units of life and every organism has one or more cells.

All organisms have DNA. DNA is the molecule that carries genetic information. Cells use DNA to produce proteins which carry out the work that cells do.

Characteristics of Living Organisms

  • Organization

  • Energy

  • Internal Constancy

  • Reproduction, Growth, Development

  • Evolution

Organization of life: Atom - Molecule - Organelle - Cell - Tissue - Organ - Organ system - Organism - Population - Community - Ecosystem - Biosphere

This organization leads to Emergent Properties - components interact, and the whole is greater than the sum of parts

  • arise at each biological organization

  • produces life complexity such as consciousness and memory

Life Requires Energy

  • Primary Producers: extract energy and nutrients from the non living environment

  • Consumers: obtain energy and nutrients by eating other organisms

  • Decomposers: Consumers that obtain nutrients from dead organisms and organic wastes

Life Requires Homeostasis

Homeostasis is the process by which a cell or organism maintains internal equilibrium

Life Requires Reproduction, Growth, Development

  • Asexual Reproduction is when one parent is involved and offspring are genetically identical to the parent

    • This is successful in unchanging environment

  • Sexual Reproduction is when two parents are involved and offspring are genetically different from each parent

    • This is successful in changing environments

  • Organisms grow and development into adults

    • Growth: an increase in an organism’s size, usually by way of cell division

    • Development: changes that occur as an organism matures, including growth, cell specialization, and other processes

Evolution

  • Genetic change over time in population

  • The reason why different organisms have different genes

    • Some organisms survive and reproduce therefore passing surviving genes

  • The environment “selects” beneficial adaptations

Taxomy

  • Used to name and classify organisms

  • 3 main domains

    • Bacteria

    • Archaea

    • Eukarya

      • Have larger, more complex cells with nuclei

      • Eukarya, Protista: Most diverse group of eukaryotes with multiple lineages like amoebas, slime molds, algae, and more

      • Eukarya, Animalia: Includes vertebrates and invertebrates and are heterotrophs by ingestion

      • Eukarya, Fungai: Nature’s decomposers and heterotrophs by external digestion

      • Eukarya, Plantae: Producers that capture light from the sun and create energy that is passed to consumers and decomposers and are autotrophs (Autotrophs)

  • Domains are divided into kingdoms

  • Then Phylum, Class, Order, Family, Genus, Species

    • Dumb King Phillip Came Over For Great Slushies

  • Domain Bacteria and Archaea consist of small prokaryotic and unicellular organisms

    • Prokaryotic: single celled organism with no membrane bound organelles

    • Eukaryotic: has membrane bound organelles

Scientific Method

A series of steps for scientific inquiry

  1. Observations and Questions

    1. consult prior knowledge

  2. Hypothesis and Predictions

    1. Hypothesis: A testable idea to answer a question

    2. A prediction allows you to test the hypothesis

  3. Data and Conclusion

    1. can either support or falsify a hypothesis

  4. Publish and Review

    1. When there is enough info, scientists submit a manuscript

    2. Each submission is reviewed by experts in its field

    3. If accepted, the manuscript is published in a peer-review journal

Components of Experiments

  • Independent Variable: What is changing

  • Dependent Variable: What is measured

  • Standardized Variable: Held constant for all subjects

  • Control Group: Baseline used for comparison

  • Experimental Group: May or may now show different results from control group

Scientific theories develop from data. A scientific theory is a broad explanation for a natural phenomenon

Chapter 1- The Scientific Study of Life 

Biology is the scientific study of life and it includes all forms of life

All organisms are made of cells. Cells are the basic units of life and every organism has one or more cells.

All organisms have DNA. DNA is the molecule that carries genetic information. Cells use DNA to produce proteins which carry out the work that cells do.

Characteristics of Living Organisms

  • Organization

  • Energy

  • Internal Constancy

  • Reproduction, Growth, Development

  • Evolution

Organization of life: Atom - Molecule - Organelle - Cell - Tissue - Organ - Organ system - Organism - Population - Community - Ecosystem - Biosphere

This organization leads to Emergent Properties - components interact, and the whole is greater than the sum of parts

  • arise at each biological organization

  • produces life complexity such as consciousness and memory

Life Requires Energy

  • Primary Producers: extract energy and nutrients from the non living environment

  • Consumers: obtain energy and nutrients by eating other organisms

  • Decomposers: Consumers that obtain nutrients from dead organisms and organic wastes

Life Requires Homeostasis

Homeostasis is the process by which a cell or organism maintains internal equilibrium

Life Requires Reproduction, Growth, Development

  • Asexual Reproduction is when one parent is involved and offspring are genetically identical to the parent

    • This is successful in unchanging environment

  • Sexual Reproduction is when two parents are involved and offspring are genetically different from each parent

    • This is successful in changing environments

  • Organisms grow and development into adults

    • Growth: an increase in an organism’s size, usually by way of cell division

    • Development: changes that occur as an organism matures, including growth, cell specialization, and other processes

Evolution

  • Genetic change over time in population

  • The reason why different organisms have different genes

    • Some organisms survive and reproduce therefore passing surviving genes

  • The environment “selects” beneficial adaptations

Taxomy

  • Used to name and classify organisms

  • 3 main domains

    • Bacteria

    • Archaea

    • Eukarya

      • Have larger, more complex cells with nuclei

      • Eukarya, Protista: Most diverse group of eukaryotes with multiple lineages like amoebas, slime molds, algae, and more

      • Eukarya, Animalia: Includes vertebrates and invertebrates and are heterotrophs by ingestion

      • Eukarya, Fungai: Nature’s decomposers and heterotrophs by external digestion

      • Eukarya, Plantae: Producers that capture light from the sun and create energy that is passed to consumers and decomposers and are autotrophs (Autotrophs)

  • Domains are divided into kingdoms

  • Then Phylum, Class, Order, Family, Genus, Species

    • Dumb King Phillip Came Over For Great Slushies

  • Domain Bacteria and Archaea consist of small prokaryotic and unicellular organisms

    • Prokaryotic: single celled organism with no membrane bound organelles

    • Eukaryotic: has membrane bound organelles

Scientific Method

A series of steps for scientific inquiry

  1. Observations and Questions

    1. consult prior knowledge

  2. Hypothesis and Predictions

    1. Hypothesis: A testable idea to answer a question

    2. A prediction allows you to test the hypothesis

  3. Data and Conclusion

    1. can either support or falsify a hypothesis

  4. Publish and Review

    1. When there is enough info, scientists submit a manuscript

    2. Each submission is reviewed by experts in its field

    3. If accepted, the manuscript is published in a peer-review journal

Components of Experiments

  • Independent Variable: What is changing

  • Dependent Variable: What is measured

  • Standardized Variable: Held constant for all subjects

  • Control Group: Baseline used for comparison

  • Experimental Group: May or may now show different results from control group

Scientific theories develop from data. A scientific theory is a broad explanation for a natural phenomenon