Bacteria

Question 1

What are the two main categories of organisms based on cellular structure?

Answer 1

Eukaryotes and Prokaryotes

Eukaryotes have a true nucleus and are often multicellular, while prokaryotes do not have a nucleus and are usually unicellular.

Question 2

What is the general size range of prokaryotic cells?

Answer 2

1-5 µm

Prokaryotic cells are typically smaller than eukaryotic cells, which range from 10-100 µm.

Question 3

What is a key characteristic of all bacteria?

Answer 3

Bacteria are prokaryotes

This means they lack a nucleus and membrane-bound organelles.

Question 4

How do bacteria reproduce asexually?

Answer 4

Binary fission

This process involves the cell growing, copying its chromosome, and splitting into two identical cells.

Question 5

What are pili in bacteria used for?

Answer 5

Transfer of plasmids

Pili allow for genetic material exchange between bacteria.

Question 6

What are the two domains that bacteria belong to?

Answer 6

Bacteria and Archaea

These domains categorize all bacteria based on distinct evolutionary traits.

Question 7

What do methanogens produce?

Answer 7

Methane

Methanogens are a group of archaea that generate methane gas, often found in extreme environments.

Question 8

What distinguishes Gram-positive bacteria from Gram-negative bacteria?

Answer 8

Gram-positive bacteria have a thick peptidoglycan wall that stains purple, while Gram-negative bacteria have a thin peptidoglycan wall and stain red

This classification is important for understanding bacterial structure and treatment.

Question 9

What is the function of endospores in bacteria?

Answer 9

Survival in unfavorable conditions

Endospores can withstand extreme conditions and allow bacteria to survive until conditions improve.

Question 10

What are the two types of nutrition that bacteria can obtain?

Answer 10

Heterotrophic and Autotrophic

Heterotrophs absorb nutrients from other organisms, while autotrophs produce their own organic compounds.

Question 11

What is a pathogen?

Answer 11

A disease-causing bacteria

Pathogenic bacteria must enter the body, evade defenses, and multiply to cause disease.

Question 12

What is antibiotic resistance?

Answer 12

The ability of bacteria to change and resist antibiotic treatments

This can occur due to genetic mutations or the acquisition of resistance genes.

Question 13

Fill in the blank: Most bacteria are _______.

Answer 13

Heterotrophs

They obtain energy by breaking down organic matter or absorbing nutrients.

Question 14

What is the role of antibiotics?

Answer 14

Fight bacterial infections by killing or harming bacteria

Antibiotics do not affect viruses.

Question 15

What are the four classifications of bacteria based on respiration?

Answer 15

• Obligate aerobes
• Obligate anaerobes
• Facultative aerobes
• Facultative anaerobes

These classifications indicate whether bacteria require oxygen for survival.

Question 16

What type of bacteria are involved in bioremediation?

Answer 16

Bacteria that can clean up oil spills and toxic waste

They play a crucial role in environmental cleanup efforts.

Question 17

True or False: All known pathogens are eubacteria.

Answer 17

True

Archaea are not known to cause diseases in humans.

Question 18

What type of bacteria is Lactobacillus bulgaricus used to produce?

Answer 18

Yogurt

This bacterium is beneficial and used in dairy fermentation.

Question 19

What color do Gram-positive bacteria stain?

Answer 19

Purple

This is due to the thick peptidoglycan layer in their cell walls.

Question 20

What does the term ‘facultative anaerobes’ refer to?

Answer 20

Organisms that can survive in both the presence and absence of oxygen

They can adapt to varying oxygen levels.

Question 21

What is the size range of eubacteria?

Answer 21

0.4 micrometres to several micrometres in length

This size variation is typical across different bacterial species.