Variety of Living Organisms Pg.4-5

Question 1

Tell me everything about bacteria

Answer 1

• Prokaryotic
• single celled
• No nuclei
• have circular chromosomes + plasmids for DNA
• have cell wall made of murein
• don’t have chloroplasts
• they feed off living or dead material but some can photosynthesise as they contain photosynthetic pigments
• stores carbohydrates as glycogen
• no nervous co-ordination
  examples:
• Lactobacillus Bulgaricus which is used to make yoghurt
• Pneumococcus which causes Pneumonia

Question 2

Tell me everything about Protoctists

Answer 2

• Eukaryotic
• Mostly single celled
• has a nucleus
• contains chromosomes in nucleus for DNA
• some have cell walls
• some have chloroplasts
• Some feed by photosynthesis and others feed on living or dead material
• stores carbohydrates as glucose or starch
• no nervous co-ordination
  examples:
• Chlorella (plant cell like)
• Amoeba (animal cell like)
• Plasmodium which causes malaria

Question 3

Tell me everything about fungi

Answer 3

• Eukaryotic
• single celled (yeast) or mycelium made from thread like hyphae (mucor)
• has a nucleus (often has many nuclei in hyphae)
• has chromosomes in nucleus for DNA
• has cell walls made of chitin
• does not have chloroplasts
• feed by extra-cellular secretion of digestive enzymes and absorption of soluble organic products (saprotrophic nutrition)
• stores carbohydrates as glycogen
• no nervous co-ordination
  examples:
• Mucor (bread mould)
• Yeast (single celled, used to make bread, bear and wine)

Question 4

Tell me everything about Plants

Answer 4

• eukaryotic
• multicellular
• has a nucleus
• has linear chromosomes in nucleus for DNA
• has cell wall made of cellulose
• feeds off photosynthesis
• stores carbohydrates as starch
• no nervous co-ordination
  examples:
• peas

Question 5

Tell me everything about Animal cells

Answer 5

• eukaryotic
• multicellular
• has a nucleus
• has linear chromosomes for DNA
• no cell walls
• no chloroplasts
• they feed as heterotrophs so they must take in organic molecules
• stores carbohydrates as glycogen
• has nervous co-ordination
  examples:
• humans
• mosquito

Question 6

Tell me everything about Viruses

Answer 6

• THEY ARE NOT CELLS
• They are small particles made up of a protein coat & genetic material (DNA OR RNA)
• No nucleus
• has DNA or RNA present (not both)
• has no cell walls
• no chloroplasts
• they do not feed, they take over other living cells for raw materials
• don’t store carbohydrates
• no nervous co-ordination
  examples:
• Tobacco virus (which prevents chlorophyll production)
• Influenza ( causes flu or fever)
• HIV (causes aids)

Question 7

What are pathogens

Answer 7

pathogens are organisms that can cause disease

Question 8

List some possible pathogens

Answer 8

fungi, protoctists, bacteria and viruses are also pathogens even if they’re not living organisms.