1 Flashcards
What do Group A Streptococci (GAS) need to grow in skeletal muscle?
Amino acids.
GAS stands for Group A Streptococcus, a type of bacteria known for causing infections.
How are nutrients transported into bacterial cells?
By transport proteins embedded in the cells’ membranes.
Are all transporters in bacterial membranes the same?
No, transporters are specific for one type of molecule.
What are examples of molecules that transport proteins can handle?
- Ions
- Amino acids
- Vitamins
- Sugars
What significant change occurred in the classification of bacteria and archaea after the 1960s?
They were previously lumped together as prokaryotes, but studies revealed distinct differences.
What are the four main shapes of bacteria?
- Cocci (coccus)
- Bacilli (bacillus)
- Spirilla (rigid spiral)
- Spirochetes
What does pleiomorphic mean in the context of bacteria?
Bacteria that lack a consistent form and can vary in shape.
What is the average size of E. coli?
1.3 x 4.0 µm (microns).
What is the size of Mycoplasma?
0.3 µm.
What is the size range of some spirochetes?
Up to 500 µm.
What is the Surface to Volume Ratio (S/V ratio) in bacteria?
Shape affects S/V ratio; rods can get nutrients faster than cocci.
What structures are found in bacterial cells?
- Plasma Membrane
- Cell Wall
- Capsule or Slime Layer
- Nucleoid
- Ribosomes and inclusions
What is the primary role of the plasma membrane in bacteria?
To be a selectively permeable barrier.
What do the plasma membranes carry out in bacterial cells?
- Respiration
- Photosynthesis
- Synthesis of lipids and cell wall constituents
What is the approximate thickness of the plasma membrane?
7-8 nm.
What are peripheral membrane proteins?
Proteins that are loosely connected to the membrane.
What are integral membrane proteins?
Proteins with hydrophobic parts buried in membrane lipids and hydrophilic parts projecting from the membrane surface.
What role do hopanoids play in bacterial membranes?
Similar to cholesterol in eukaryotic membranes.
What nutrients are classified as macronutrients for bacterial cells?
- Carbon
- Oxygen
- Hydrogen
- Nitrogen
- Sulfur
- Phosphorus
Fill in the blank: Cationic macronutrients include _______.
Potassium, Calcium, Magnesium.
What are examples of micronutrients required by bacterial cells?
- Manganese
- Zinc
- Cobalt
- Iron
- Copper
- Nickel
What are growth factors needed by bacteria?
- Amino Acids
- Purines
- Pyrimidines
- Vitamins
True or False: The cell envelope consists of only the plasma membrane.
False.
