Bio 104 Ch.13

MRSA sickens some 75,000 people in the United States each year and kills almost:

10,000

Which step is NOT involved in bacterial reproduction?

Daughter cells stay attached.

How are humans affected by antibiotics used to treat farm animals?

Food-borne pathogens such as Salmonella or Campylobacter can develop antibiotic resistance within the animals and enter humans' food source.

An athlete came to the clinic with red swollen skin, chills, and nausea. Doctors tried every antibiotic, including vancomycin, penicillin, and cephalosporin, to alleviate these symptoms. What condition is the athlete likely to have?

MRSA

Two bacterial samples obtained from siblings test positive for staph. The siblings are both prescribed beta-lactams and sent home. Sibling 1 fully recovers and has no visible signs of illness, whereas sibling 2 remains severely ill with fever and vomiting. Which statement is NOT a reason the antibiotics may not have been effective in sibling 2?

The bacteria may have hidden behind specific organelles to avoid detection.

An antibiotic-resistant allele confers a fitness cost. What would be predicted about the growth of the bacteria with the resistant allele compared to the growth of bacteria without the sensitive allele in the presence or absence of antibiotics?

The sensitive strain will have the highest fitness in the absence of antibiotic, and the resistant strain will have the highest fitness in the presence of antibiotic.

How do beta-lactam antibiotics kill sensitive bacteria? Please choose the correct answer from the following choices, and then select the submit answer button. Answer choices

by destabilizing the cell wall

A type of natural selection in which organisms with phenotypes at both extremes of the phenotypic range are favored by the environment is:

diversifying selection.

Although MRSA can cause death, the bacteria cannot eat through skin.

false

Where is MRSA MOST likely to be a problem?

in the bloodstream

Fitness is determined by the interaction between _____ and the environment.

phenotype

A college basketball player suddenly develops a skin rash on the back. Test results show that the infection is caused by MRSA. How may have this infection been contracted?

shared towels

On which part of the body is staph MOST likely to reside?

skin

Which region of the body contains species of bacteria that are considered helpful?

skin

MRSA is composed of several unique strains of staph bacteria.

true

Staph bacteria cause no harm to most of the people who carry them.

true

Which of the following is NOT a beta-lactam?

vancomycin