Chapter 25 Quiz

Botox is the marketed version of the botulism exotoxin, used to treat muscle spasms and for cosmetic purposes.

True

Which was the first bacterium to be clearly identified as the cause of an infectious disease?

Bacillus anthracis, which causes anthrax

What is the purpose of sex pili?

To transmit DNA between bacteria

Which structure in the accompanying figure is labeled as C?

capsule

Bacterial chemoautotrophs use organic chemicals as an energy source.

False

The most significant difference between archaea and bacteria is the:

absence of peptidoglycans in the cell walls of archaea.

Although bacteria lack membrane-bound organelles, such as chloroplasts and mitochondria, they can still perform the functions of these organelles by localizing certain metabolic enzymes on:

the plasma membrane.

Which statement about biofilms is FALSE? -Biofilms are formed by bacteria living in a watery environment. -Biofilms enable bacteria to attach to solid surfaces. -Biofilm may develop on surgical implants. -Biofilms are usually less than 2 μm thick. -An example of biofilm is dental plaque.

Biofilms are usually less than 2 μm thick.

What is the function of the structure labeled as B in the accompanying figure? -To provide locomotion -To prevent phagocytosis -To carry genetic information -To transmit DNA between bacteria -Answer To adhere to surfaces or other bacteria

To adhere to surfaces or other bacteria

Which statement about bioremediation is FALSE? -Methogens are used in sewage treatment. -When bacteria break down toxins, they leave behind harmless byproducts. -Very few species of bacteria are used to clean up various forms of pollution. -Bacteria and other microorganisms are used to break down oil from oil spills. -The byproducts of microorganisms breaking down toxins are often carbon dioxide and chlorides.

Very few species of bacteria are used to clean up various forms of pollution.