Lecture 01

• What are the hallmarks of life represented by MRS GREN?

  Movement, Reproduction, Sensitivity, Growth, Respiration, Excretion, Nutrition
• Why are viruses considered not alive?

  They rely on host cells for reproduction
• Who proposed the cell theory in 1839?

  Schwann and Schleiden
• What does the cell theory state?

  All living things are made of cells
• What is the largest organelle in a cell?

  Rough endoplasmic reticulum
• What are the three domains of life?

  Bacteria, Archaea, Eukarya
• Where do Archaea typically thrive?

  Extreme environments like bogs and volcanoes
• What is a key role of cyanobacteria in ecology?

  They play a key role in ecology and evolution
• What shapes can prokaryotes take?

  Rods, balls, helices
• What is Bifidobacterium classified as?

  Gram-positive, non-motile anaerobic bacillus
• What vitamin does Bifidobacterium help synthesize?

  Vitamin K
• Where is Bifidobacterium commonly found?

  In the gastrointestinal tract
• What is Helicobacter pylori's oxygen requirement?

  Microaerophilic (requires O2)
• How does Helicobacter pylori adapt to the human stomach?

  It secretes urease to reduce acidity
• What role does flagella play for Helicobacter pylori?

  Helps to propel and burrow in the stomach lining
• What distinguishes Gram-negative bacteria?

  Thin peptidoglycan layer

  
• What distinguishes Gram-positive bacteria?

  Thick peptidoglycan layer

  
• How can bacterial cell walls be identified?

  Using lab techniques like gram staining
• What is the purpose of immersion oil in microscopy?

  Improves imaging and resolution

  
• What type of bacteria are mitochondria thought to have originated from?

  Free living aerobic bacteria
• What does the endosymbiotic theory propose?

  Free living bacteria were engulfed by larger cells
• What type of bacteria are chloroplasts thought to have originated from?

  Cyanobacteria (photosynthetic prokaryotes)
• What is unique about mitochondrial and chloroplast DNA?

  It is closely related to prokaryotic DNA
• What are the positive and negative aspects of prokaryotes?

  Positive:

  • Provide vitamins
  • Assist with decomposition
  • Prevent pathogen colonies
  • Crucial to life

  
  

  Negative:

  • Cause food poisoning
  • Can lead to dental disease
  • May cause septicaemia
  • Can be opportunistic pathogens
• What is the definition of filamentous?

  • An elongated thin series of cells
  • Attached one to another
  • A very long thin cylindrical single cell
• What does microaerophilic mean?

  • Requiring very little free oxygen
• What are complex appendages?

  • Body parts attached to the main body
  • Examples include arms and legs