Bacteria Flashcards
What are the observed shapes of bacteria?
Cocci (spherical), Bacilli (rod-shaped), Spirilla (spiral-shaped)
How can bacteria be arranged?
Singles (mono), Doubles (diplo), Chains (strepto), Clusters (staphylo)
What is the function of the capsule in a bacterial cell?
Protects bacteria from drying out and helps evade immune response.
What is the function of the cell membrane in a bacterial cell?
Controls movement of substances in and out.
What is the function of the cell wall in a bacterial cell?
Provides structural support and shape; protects against osmotic pressure.
What is the function of the cytoplasm in a bacterial cell?
Contains enzymes and nutrients; site of biochemical reactions.
How do bacteria reproduce?
Asexual reproduction by separation of the body into two new bodies.
What is conjugation in bacteria?
One bacterium transfers genetic material to another through direct contact.
What are the types of bacterial nutrition?
Heterotrophs, Autotrophs, Phototrophs, Chemotrophs.
What is the role of saprophytic bacteria?
Feed on dead or decaying organic matter, contributing to nutrient recycling in ecosystems.
Example: Bacillus subtilis decomposes plant material and organic waste.
What are parasitic bacteria?
Live in or on a host organism and derive nutrients at the host’s expense, causing harm.
Example: Mycobacterium tuberculosis infects the lungs of humans.
What are commensal bacteria?
Live on or within a host organism, benefiting without harming the host.
Example: Escherichia coli in the human intestines.
What are pathogenic bacteria?
Can cause disease in their host by releasing toxins or damaging host tissues.
What are mutualistic/symbiotic bacteria?
Both bacteria and host benefit, aiding in processes like digestion and immune regulation.
Example: Lactobacillus acidophilus aids in digestion.
What is the difference between Gram-positive and Gram-negative bacteria?
Gram-positive have a thick protein layer and stain purple; Gram-negative have a thin protein layer and stain pink.
