Monera

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21 ­ Bacteria (Monera) Bacteria are very small. They are measured in µm (nanometres). There are 1000 nanometres in 1 mm. Bacteria can be 1 µm in size. Bacteria have a cell wall that protects them from bursting due to osmosis. It's made from sugar and protein. Bacteria have no nucleus but do have a chromosome or plasmid. A plasmid is a loop of DNA that helps it be resistant to antibiotics. Also known as prokaryotes as they have no true nucleus or membrane bound cell organelles.

1. To which kingdom do yeasts belong? 2. To which kingdom does Rhizopus belong? 3. What term is used for the form of asexual reproduction in bacteria? 4. Describe two ways in which the skin helps to defend the body against pathogenic microorganisms. 5. What does the term pathogenic mean in relation to bacteria? 6. What do bacteria form when environmental conditions become unfavourable? 7. Other than being prokaryotic, state two ways in which a typical bacterial cell differs from a typical human cell (e.g. cell from cheek lining). 8. What are antibiotics? 9. Describe how some bacteria respond in order to survive when environmental conditions become unfavourable. 10. What is meant when a bacterium is described as being pathogenic? 11. To which kingdom do bacteria belong? 12. Distinguish between photosynthetic and chemosynthetic bacteria. Give an example of each type. 13. Name two forms of heterotrophic nutrition found in bacteria. 14. Explain what is meant by antibiotic resistance and suggest how it may develop. 15. What is a nutrient medium? 16. Give two meanings for the term sterile. 17. What is an antibiotic? 18. Antibiotics should not be prescribed for a person suffering from a viral infection. Sug

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