Chapter 1: Evolution, Themes of Biology and Scientific Inquiry 

1.1 Inquiring About Life

  • ==An organism’s adaptations to its environment are the result of evolution.==   * Adaptation is a trait to help survive/reproduce.     * ==Example: The color of the beach mouse has come to be well adapted to its local background.==   * Evolution is the process of change that has transformed life on Earth.

1.2 The Study of Life Reveals Unifying Themes

  • The five unifying themes:
  1. Organization
  2. Information
  3. Energy and Matter
  4. Interactions
  5. Evolution

1.3 New Properties Emerge at Successive Levels of Biological Organization

  • Life can be studied at different levels, from molecules to the entire living planet.
  • This enormous range can be divided into different levels of biological organization.   * Molecules   * Organelles   * Cell   * Tissues   * Organs   * Organisms   * Populations   * Communities   * Ecosystem   * Biosphere
  • Cell is the simplest living thing.
  • Population are the individuals of the same species.
  • Communities are many populations.
  • Ecosystems are living and non-living things.

1.4 Structure and Function

  • “Form fits function” is the shape of something is going to determine what is does, and if you figure out what it does, you figure out what it looks like.   * ==Example: If something can fly, it would have wings. If it has gills, it lives in the water.==

1.5 The Cell: An Organism’s Basic Unit of Structure and Function

  • ==The smallest unit of organization that is alive is called a cell.==
  • Cells have a membrane that pick and choose which materials enter and exit.
  • Cells major division:
  1. Prokaryotic is the “before nucleus”/lack a nucleus (Bacteria and Archaea), simpler and smaller with no organelles.
  2. Eukaryotic is a “true nucleus”/have a true nucleus and has organelles.

1.6 Life’s Processes Involve the Expression and Transmission of Genetic Information

  • Cells contain chromosomes which contains DNA (deoxyribonucleic acid)
  • ==Humans contain 23 pairs of chromosome, with a total of 46 chromosomes.==

1.7 DNA, the Genetic Material

  • Each chromosomes contain hundred of thousand of genes.
  • ==The purpose of these genes are to code for different molecule which are proteins.==
  • Fertilized egg is called a zygote.
  • DNA molecule is in the form of a double helix.
  • Each chain is made up of building blocks called nucleotides which are A, G, C, and T.
  • ==The sequence of the A, G, C, T nucleotides are instructions to building a protein.==
  • Gene expression go from DNA to protein:
  1. DNA is copied into RNA by a process called transcription
  2. The mRNA is translates into protein.

1.8 Life Requires the Transfer and Transformation of Energy and Matter

  • Energy from the sun makes life possible.
  • Producers convert sunlight  into food (chemical energy). This process is called photosynthesis.
  • Consumers feed on other organisms.
  • Energy flows, entering the planet as light, exiting as heat.
  • Chemical is reused over and over again.
  • ==ENERGY FLOWS AND CHEMICAL IS CYCLED.==

1.9 An Organism’s Interactions with Other Organisms and the Physical Environment

  • In an ecosystem, each organism interacts with other organisms and the environment.
  • It can be beneficial like two creatures helping each other or harmful like lion eating antelope.
  • Humans over 150 years burned fossil fuels that released carbon dioxide which lead to global warming and is one aspect of climate change.

1.10 The Three Domains of Life

  • ==Bacteria & Archaea (Prokaryote), and Eukarya (Eukaryote) are the three domains of life.==
  • Eukarya includes plants, fungi, animals and protists.
  • Protists are eukaryotes that are not plant/animal or fungus
  • Plants are producers.
  • Fungi are decomposers.
  • Animals are consumers.
  • Protist are algae, amoeba, paramecium.
  • ==The difference between archaea and bacteria is that archaea only lives in extreme hot conditions, height salt conditions==

1.11 Unity in the Diversity of Life

  • All organisms have DNA as their instructions.
  • All living things are made of cells.

1.12 Charles Darwin and the Theory of Natural Selection

  • Darwins main two points
  1. “Descent with modification”- change over time/generations
  2. “Natural selection”- pick/choose by environment who survives
  • Darwins main points is the reason we see unity and diversity:

 1. Unity means that all creatures are related

         1. Example: (birds) beak, feathers, wings, claws, no teeth, lay eggs     2. Same unity because their ancestors had these qualities  2. Diversity means that it changes over time

         1. Example: (birds) mobility, environment, color, shape, size     2. Same diversity because of changes over time which is the descent with modification due to modification  3. Darwin most fascinated by finches’ beaks  4. Darwin observed population differences in their traits which many seem to be heritable (passed down).  5. More offspring are produced than survived. This means there is going to be a competition. “Survival of the Fittest”  6. Best suited to the environment you would survive and reproduce. “If you are FIT, you would live and reproduce.” “If you re not FIT, you will die.”  7. Those born with helpful traits that may help them camouflage themselves from predators are more FIT and live to reproduce.  8. Over time, population will change.  9. Unequal Reproductive Success- some individuals will leave MORE offspring than others.

  1. The environment picks who would survive and reproduce and who would die.
  2. Natural selection results in the adaption.

         1. Example: Bat wings are an example of adaption.

  1. Darwin said that an ancestral species can give rise to two or more descendant species which is illustrated in a treelike diagram.

1.13 Exploration and Observation

  • Data
  1. Qualitative
  2. Quantitative
  • Hypothesis is an educated guess, testable
  • The independent variable is what was manipulated, changed
  • The dependent variable is the thing that is being measured.

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