Chapter 1: Introduction to biology

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Chapter 1 Introduction to biology
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Overview of chapter 1 introduction to biology

• 1. How is life organized?
• 2. What are some organisms that we could study?
• 3. What is evolution?
• 4. How do we study science the scientific
  method?
• At the end, we will do an exercise on chapter 1
  so I can see if you understand the material

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Part 1 How is life organized?

• Look from the very complex to the very simple
• Complex includes everything
• All organisms and environments
• Simplest
• What is the smallest part of an organism?

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Different levels of organization of life
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Different levels of organization

• Biosphere
• Ecosystem
• Community
• Population
• Organism
• Organ system
• Organs
• Tissue
• Cells
• Organelles
• Molecules
• Atoms

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Biospheres

• All environments on earth that support life
  -land, water and lower atmosphere

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Ecosystems

• All the organisms living within a particular area
  and the nonliving, physical components of the
  environment in which the organisms interact
• soil, water, sunlight

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Community

• All the organisms inhabiting an ecosystem

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Population and organisms

• Population
• Interacting group of individuals of one species
• Organism
• One individual in the population

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Organ systems and organs

• Organ system
• A system within the organism
• Examples circulatory system, digestive system,
  nervous system
• Organs
• Make up the organ systems
• Brain, spinal cord and nerve that transmit
  information that make up the nervous system
• several organs work together to perform a
  specific function

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Tissues and cells

• Tissues
• Make up organs
• Each with a specific function and made of similar
  cells
• Nervous tissue
• Cells
• Enclosed in a membrane
• Nerve cells or neurons

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Organelles

• Perform specific functions in the cell
• We will study organelles in chapter 4
• Nucleus location of DNA, your hereditary
  material
• Mitochondria energy

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Molecules and atoms

• Molecules
• Atoms held together by chemical bonds
• Atom
• The smallest particle of matter (chapter 2)

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2. What are some classes of organisms that we
could study?

• Producers
• Consumers
• Decomposers

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Ecosystem who are the producers, consumers and
decomposers?
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What is the role of producers in an ecosystem?

• Plants (producers) take in sunlight, carbon
  dioxide and water
• Plant provide food for an ecosystem by performing
  photosynthesis
• Light CO2 Water Glucose oxygen
• (Sun) (air) (soil)
• Plants also absorb minerals from the soil and
  incorporate them into molecules

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What is the role of consumers in an ecosystem?

• Consumers eat plants and other animals
• Aerobic respiration opposite of photosynthesis
• Glucose oxygen carbon dioxide water
• Return carbon dioxide to the environment
• Wastes from consumers return chemicals to the
  environment

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What is the role of decomposers in an ecosystem?

• What are examples of decomposers?
• Bacteria, fungi and small organisms in the soil
• Decompose the remains of dead organisms
• recyclers change dead mater into mineral and
  nutrients that plants can use

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There is a recycling of chemical nutrients in an
ecosystem

• Remember, plants and animals do reverse things
• The products they give off or make are used by
  the other organism
• But, ecosystems can lose energy
• Some of the energy is converted to heat and is
  lost from the ecosystem

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2. Different types of organisms/cells

• Different domains of life?
• What is life?
• Different domains
• Bacteria and Archae Prokaryotes No nucleus
• Eukarya Eukaryotes Have a nucleus

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Which are prokaryotes and which eukaryotes?
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Prokaryotes vs. Eukaryotes

• Prokaryotic cells Bacteria (also Archae)
• Simple, small
• No membrane bound organelles
• DNA is in the central region of the cell
• Eukaryotic cells Plants, animal, fungi
• Complex, larger
• Membrane bound organelles
• DNA in the nucleus

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Structure of prokaryote and eukaryote cell
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All forms of life have common features DNA (and
RNA)
DNA 2 CHAINS RUN IN OPPOSITE CHAINS ARE
COMPLEMENTARY TO EACH OTHER 4 BASES A, T, G
AND C
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DNA and RNA are made up of nucleotides