Classification

• Scientific names have no spaces between words and are written in italics or underlined.
• Classification systems allow us to organize living things into groups based on similarities and differences.
• The Linnaean system is used to classify all known life forms.
• Species are the smallest unit of classification and refer to individual organisms or populations within a larger group.
• Scientific names consist of two parts - genus (capitalized) followed by species name (lowercase).
• Bacteria have prokaryotic cells without nuclei or membrane-bound organelles.
• A species is a group of organisms of common ancestry that closely resemble each other and are normally capable of interbreeding to produce fertile offspring.
• Prokaryotes have cells that membrane bound organelles, so their DNA is free in the cytoplasm
• Eukaryotes have cells that contain a nucleus and membrane bound organelles
• Viruses make up a group of organisms without any cellular structure and are made up of a piece of DNA or RNA surrounded by a protein coat and can only reproduce inside other living cells.
• Animals are heterotrophic (cannot synthesize food) and use energy from plants or other animals through ingestion.
• Plants have chlorophyll to capture sunlight and convert it into chemical energy used for growth.
• Protists are unicellular eukaryotes that can be autotrophic (produce their own food) or heterotrophic (consume organic matter).
• Classification helps us understand how different living things are related to each other.
• Internal structures, developmental patterns, life cycles and electron microscopic techniques are also used to classify organisms.
• Prokaryotes includes bacteria and blue-green algae
• Protoctista cells have a true nucleus surrounded by a membrane and other membrane-bound organelles.

  • Protozoans are animal-like and ingest food or absorb food.
  • Algae are plant-like, contain chlorophyll and make their own food by photosynthesis.

  Most protoctista are unicellular, some are simple multicellular organisms that lack any complex development of tissues or organs.
• Protoctista includes the protozoa and algae
• Animals are eukaryotic, multicellular, heterotrophic (feed on other living things) and have specialised body parts called tissues which work together to carry out different functions within an organism
• Plants are eukaryotic, multicellular, autotrophic (make their own food using energy from sunlight), they have specialised body parts called tissues which work together to carry out different functions within an organism
• Chordata includes vertebrates such as fish, amphibians, reptiles, birds and mammals
• Bacteria is prokaryotic, single celled, autotrophic/heterotrophic and can be found everywhere including extreme environments
• Protista is made up of unicellular or simple multicellular organisms that lack true tissue organisation
• Fungi includes molds, yeasts, and mushrooms.
• Fungi cells have cell walls that contain chitin, which is a polysaccharide.

  Fungi cells lack chlorophyll.

  Most fungi reproduce by spores.

  Fungi feed by absorbing food.

  Most fungi are multicellular with a body composed of microscopic threads called Hyphae and a few are unicellular.
• Plantae (plants) are multicellular organisms.

  Plant cells have a cell wall made of cellulose.

  Plant cells contain chlorophyll.

  Plants make their own food by photosynthesis.

  Plants are stationary organisms.
• Animalia (animals) are multicellular organisms that have a body cavity, a nervous system, and a circulatory system.
• Animals cells lack cell walls and chlorophyll.

  Animals by ingesting food.

  Most animals move their whole bodies from place to place.