Biology Exam Revision Notes

Bacteria, Fungi, and Viruses

1. Role of Antibiotics

  • Killing Bacteria and Fungi:
  • Antibiotics are effective treatments for bacterial and fungal infections.
  • Common antibiotics include penicillin and methicillin.

2. Function of Maggots in Healing

  • Maggots' Role:
  • Remove or kill bacteria/pathogens to help treat infections.
  • Consume only dead tissue, thereby promoting healing without harming live flesh.

3. Digestive Enzymes

  • Types of Digestive Enzymes:
  • Protease: breaks down proteins
  • Lipase: breaks down fats
  • Amylase: breaks down carbohydrates.

4. Immune Response

  • White Blood Cells:
  • Types include phagocytes and lymphocytes.
  • Phagocytosis: ingestion and digestion of pathogens.
  • Antibodies help neutralize pathogens.

5. Resistance to Antibiotics

  • Reasons for Resistance:
  • Variations among bacteria can lead to some being resistant to antibiotics.
  • Mutations can occur allowing for survival and reproduction of resistant strains.

6. Structure of Organisms

  • Bacteria vs. Fungi vs. Viruses:
  • Bacteria: have a cell wall, no nucleus.
  • Fungi: have a nucleus, cell wall made of chitin.
  • Viruses: lack cellular structure; contain either DNA or RNA but not both.

7. Disease-Causing Organisms

  • Types of Pathogens:
  • Bacteria, viruses, protozoa, and fungi.
  • Common Diseases: Malaria, dysentery, and sleeping sickness caused by protozoan pathogens.

8. Viruses Specifics

  • Characteristics:
  • Cannot reproduce outside a host.
  • Do not exhibit characteristics of living organisms such as metabolism or growth.

9. Mutation and Evolution

  • Process:
  • Mutations in genes can lead to variations that help some bacteria survive antibiotic treatments.
  • Only those that survive can reproduce and pass on resistant traits.

10. Ecological Impacts of Invasive Species

  • Impact of Invasive Species:
  • They compete with native species for resources such as light, space, and nutrients.
  • Can lead to declines in native populations and disruptions in ecosystems.

11. Nutritional Characteristics of Organisms

  • Nutrition across Groups:
  • Bacteria and Fungi: Require nutrients, respire, and can be pathogenic.
  • Protoctists: Some are photosynthetic and have complex structures.

12. Infection Prevention

  • Strategies:
  • Ensure thorough elimination of pathogens to prevent disease spread and ensure effectiveness of treatments.

13. Antigen and Immune Response

  • Vaccination Process:
  • Involves introduction of antigens to stimulate antibody production.
  • Memory cells are formed for quicker response in future infections.

14. Importance of Good Hygiene

  • Killing Pathogens:
  • Proper hygiene reduces the spread of infections and increases health safety.
  • Methods include washing hands, sanitizing surfaces, and proper food preparation.

15. Genetics and Inherited Traits

  • Passing on Traits:
  • Variations arise due to mutations that create new alleles.
  • Successful individuals pass these on across generations, shaping evolution over time.