Bacteria Lecture Notes

These flashcards cover the essential concepts regarding bacteria, their classification, structures, effects, and methods of killing them. They are designed to help students review for their exam.

Characteristics of bacteria

Bacteria are prokaryotes, single-celled, have no membrane-bound organelles, no nucleus, and usually one circular chromosome.

Gram + bacteria.

Bacteria that retain the violet color when stained using the Gram stain

Which bacteria are generally more resistant to antibiotics and often more dangerous?

Gram - bacteria.

What are the different shapes of bacteria classified by?

Coccus (spheres), Bacillus (rod-shaped), Spirillum (corkscrew-shaped).

What are the prefixes used for grouping bacteria?

Diplo (pairs), Staphylo (clumps), Strepto (chains).

What are aerobic bacteria?

Bacteria that require oxygen to live.

Explain the term 'mutualism' in relation to bacteria.

Mutualism is when bacteria help a host, such as aiding in digestion.

What is the germ theory of disease?

The theory proposed by Louis Pasteur that describes how bacteria cause illness by interfering with normal cell functioning, destroying cells, or producing toxins.

What is Koch’s postulates used for?

To determine if a specific pathogen (e.g. bacteria) causes a specific disease.

What are some methods of killing bacteria?

Antiseptics, antibiotics, and human defenses like skin and immune responses.

Name one harmful effect of bacteria.

Bacteria can be harmful when they cause food decay to foods like meat, dairy and vegetables

What is one helpful effect of bacteria?

Bacteria helps in producing vitamins like vitamin K in the body

What are heterotrophic bacteria?

Bacteria that obtain food from other organisms.

What do B-cells do in the immune response against bacteria?

They make antibodies.

Give an example of a facultative anaerobe.

E. Coli.

What structure in bacteria is responsible for movement?

Flagella.

What chemical makes up the bacterial cell wall?

Peptidoglycan.

What are obligate anaerobes?

Organisms that cannot survive in the presence of oxygen and may be harmed or killed by it, relying only on anaerobic processes for energy.

What are facultative anaerobes?

Organisms that can grow in both oxygen-rich and oxygen-free environments. They prefer anaerobic conditions but are capable of aerobic respiration when oxygen is present.

What are aerotolerant anaerobes?

Organisms that do not require oxygen for growth and are not harmed by its presence; they can survive in oxygen-rich environments but do not use it for metabolism.

What are microaerophilic anaerobes?

Organisms that require oxygen but at lower concentrations than what is found in the atmosphere, thriving in environments with reduced oxygen levels