VARIETY OF LIVING ORGANISMS

• Bacteria cell

  Cell membrane, cell wall, cytoplasm, plasmids, chromosome loop of DNA, ribosomes, flagellum
• Are bacteria prokaryotic or eukaryotic organisms?

  Prokaryotic
• Are plants prokaryotic or eukaryotic organisms?

  Eukaryotic
• Are animals prokaryotic or eukaryotic organisms?

  Eukaryotic
• Are fungi prokaryotic or eukaryotic organisms?

  Eukaryotic
• Are protoctists prokaryotic or eukaryotic organisms?

  Eukaryotic
• What classifies an organism as eukaryotic?

  There is a nucleus present, unlike in prokaryotes that just have a chromosome loop of DNA
• Examples of plants

  • Flowering plants - corn and maize
  • Herbaceous legumes - peas and beans
• Example of animals

  • Mammals - humans
  • Insects - housefly and mosquito
• Examples of bacteria

  • Lactobacillus bulgaricus - rod-shaped bacterium used in the production of yoghurt from milk
  • Pneumococcus - spherical bacterium that acts as the pathogen causing pneumonia
• Fungi cell

  Cell wall, cell membrane, nucleus, cytoplasm, vacuole, ribosome, mitochondria
• What are fungal cell walls made out of?

  Chitin
• Examples of fungi

  • Mucor - has the typical fungal hyphal structure
  • Yeast - is single-celled, used in making bread, beer and wine
• Fungal hyphal structure

  Their body is usually organised into a mycellium made of thread-like structures called hyphae, which contain many nuclei. Some are single-celled.
• How do fungi feed?

  They feed by extracellular secretion of digestive enzymes onto food material and absorption of the organic products, this is known as saprotrophic nutrition.
• Examples of Protoctists

  • Amoeba - live in pond water, features like animal cells
  • Chlorella - have chloroplasts, features like plant cells
  • Plasmodium - responsible for causing malaria, pathogenic
• Are plants multicellular or unicellular?

  Multicellular
• Are animals multicellular or unicellular?

  Multicellular
• Are protoctists multicellular or unicellular?

  Unicellular
• Are bacteria multicellular or unicellular?

  Unicellular
• Viruses

  Do not have a cellular structure but have one type of nucleic acid (RNA or DNA) and have a protein coat
• Examples of viruses

  • Tobacco mosaic virus (TMV) - prevents chloroplast formation, causing discolouration of tobacco plant leaves
  • Influenza virus (Flu)
  • HIV virus - leading to aids
  • Mumps
  • Measles
• Why are viruses non-living organisms?

  They can only reproduce within living cells, they need a host
• Pathogens

  Disease-causing organisms that can be fungi, bacteria, protoctists or viruses
• Plant features

  • Multicellular organisms
  • Cells contain chloroplasts that contain chlorophyll, which is used in photosynthesis
  • Cells have cellulose cell walls to support and strengthen the cell
  • Store carbohydrates as starch or glucose
• Animal features

  • Multicellular organisms
  • Do not have a cell wall, only cell membrane
  • Do not have chloroplasts, so cannot photosynthesise
  • Have nervous systems in order to coordinate movement
  • Can usually move from one place to another
  • Store carbohydrates as glycogen
• Fungi features

  • Cannot photosynthesise
  • Some are single-celled
  • Others have a body called a mycelium, made up of hyphae (thread-like structures). Hyphae contain many nuclei
  • Cells have cell walls made of chitin
  • Most feed by saprotrophic nutrition
  • Store carbohydrates as glycogen
• Saprotrophic nutrition

  Secretion of extracellular digestive enzymes into the area outside their body to dissolve/break down their food, so they can then absorb the nutrients
• Protoctist features

  • Single-celled organisms and microscopic
  • Some have chloroplasts and are similar to plant cells, such as Chlorella
  • Some hare more like animal cells, such as Amoeba that live in pond water
  • Pathogenic example is Plasmodium, responsible for causing malaria
• Bacteria features

  • Single-celled organisms and microscopic
  • Do not have a nucleus, instead have a circular chromosome of DNA
  • Contain plasmids
  • Some can photosynthesise
  • Most feed off other organisms, dead or living
• Virus features

  • Not living organisms
  • Small particles, smaller than bacteria
  • They are parasitic - can only reproduce inside living cells, depends on other organisms to grow
  • Infect every type of living organisms
  • Wide variety of shapes and sizes
  • Do not have a cellular structure - have a protein coat around some genetic material/nucleic acid (DNA or RNA)