Classification of Life
Part 1: The Domains Classification
• the process of grouping things according to similarities.
Living vs. Non-Living
Living (Biotic) Non-Living (Abiotic) • Contain one or more cells • Not made of cells • Are able to: • Unable to grow, – Respond to stimuli from its reproduce, or respond to surroundings stimuli. – Use chemicals to • Grow • Reproduce – Maintain stable internal living conditions
“Need to Know” Vocab Review • Eukaryotic • Prokaryotic • Unicellular • Multicellular • Autotrophic • Heterotrophic • Extremophile • Decomposer
NEW: Write these down in your notes! • Sexual Reproduction – The union of two parent cells to form an offspring
• Asexual Reproduction – Formation of an offspring from a single parent cell (exact copy).
Classification of Life
– Living things are split into many different categories called Domains.
– A domain is the largest group in which living things are classified. i.e. There are more organisms grouped in a domain than a kingdom, phylum, etc.
– There are 3 Domains of Life • Archaea • Bacteria • Eukarya Domain Archaea
– The oldest of all life (“archaea” means ancient)
– Prokaryotic cell structure (no nucleus)
– Unicellular and Microscopic
– Reproduce asexually
– No cell parts (organelles)
– Genetic material free-floats in the cell
– Found in extreme environments ( named “extremophiles”) including in animal digestive systems (methanogens). No other living thing can live in these environments. Where to Find Extremophiles…
Extremophiles live in extreme (places where most life could not exist) conditions.
– These locations include:
• Highly acidic regions • Extreme cold/hot temperature • Hot springs • High radiation • High salt regions • Sulfur vents at the bottom of the oceans
Domain Bacteria Rod Shaped Bacteria
– Prokaryotic cell structure (no nucleus)
– Microscopic
– Reproduce asexually
Sphere Shaped Bacteria – No cell parts (organelles)
– Genetic material free-floats in the cell
– Three basic shapes • Rods • Spheres (Coccus) • Spirals
Spiral Shaped Bacteria
What is the difference between Archea and Bacteria?
• 15 seconds to think…
• 30 seconds to discuss with your neighbor the difference between archea and bacteria.
• 30 seconds to write the difference in your notebook. Domain Eukarya
– The word eukaryote (eu- “true”/ karyo- Platypus “nucleus” /ote- “having to do with”) describes organisms that have a nucleus
– These organisms have a nucleus inside of their cells
– Some unicellular, some multicellular
Protozoa Domain Eukarya – The nucleus of a cell controls the function of a cell and holds all the genetic material for the cell (similar to what the brain does for a body)
– You have seen nuclei when we observed plant cells and protists under the microscope. That’s because plants and protists are classified in domain Eukarya.
– Organisms in the Domain Eukarya are more complex than the organisms in the Domain Bacteria and Domain Archaea
– Organisms in the Domain Eukarya include: • plants • animals • fungi • protists
Agree or Disagree? Amoeba proteus and Justin Bieber are both classified into domain Eukarya.
Agree – Go to one side of the room Disagree – Go to opposite side of the room Debate!