Bacterial Diseases

An important cause of tooth decay by the bacterium Streptococcus mutans is because of their ability to attach to teeth surface by producing slime layer from

[amp_mcq option1=”Sugar” option2=”Alcohol” option3=”Saliva” option4=”Teichoic acid” correct=”option1″]

Streptococcus mutans metabolizes dietary sugars, particularly sucrose, to produce acids that demineralize tooth enamel (causing decay) and to synthesize extracellular polysaccharides (glucans and fructans). These sticky polysaccharides form a ‘slime layer’ or matrix which allows the bacteria to adhere firmly to the tooth surface and form dental plaque (biofilm).

Streptococcus mutans is a key bacterium in the initiation of dental caries (tooth decay). It produces both acid and a sticky matrix from fermentable carbohydrates, primarily sugars.

While saliva plays a role in buffering acids and clearing food debris, it is not used by the bacteria to produce the sticky layer. Teichoic acid is a component of the bacterial cell wall, contributing to cell shape and adhesion, but the bulk of the slime layer is composed of polysaccharides synthesized from dietary sugars. Alcohol is generally not relevant to this process in the context of dietary intake leading to decay.

Which one of the following is a bacterium that causes disease in the human body ?

[amp_mcq option1=”Varicella zoster” option2=”Trypanosoma gambiense” option3=”Salmonella typhi” option4=”Plasmodium falciparum” correct=”option3″]

The correct option is C) Salmonella typhi.

The question asks to identify a bacterium from the given options that causes disease in humans.

Salmonella typhi is a rod-shaped, Gram-negative bacterium that causes typhoid fever in humans. Varicella zoster is a virus (causes chickenpox and shingles). Trypanosoma gambiense is a protozoan (causes African sleeping sickness). Plasmodium falciparum is a protozoan (causes malaria).

Which one of the following is caused by a bacterial pathogen?

[amp_mcq option1=”AIDS” option2=”Dengue fever” option3=”COVID-19″ option4=”Typhoid fever” correct=”option4″]

Typhoid fever is caused by the bacterium *Salmonella Typhi*. AIDS is caused by the Human Immunodeficiency Virus (HIV). Dengue fever is caused by the Dengue virus. COVID-19 is caused by the SARS-CoV-2 virus. Therefore, Typhoid fever is the only disease among the options caused by a bacterial pathogen.

Pathogens can be viruses, bacteria, fungi, or parasites. It is important to know the type of pathogen causing common diseases.

Typhoid fever is typically spread through contaminated food or water. It is a serious illness characterized by high fever, fatigue, abdominal pain, and sometimes a rash. Antibiotics are used to treat bacterial infections like typhoid fever.

Which one of the following statements regarding Cholera is correct ?

[amp_mcq option1=”Cholera is a disease that causes loss of memory” option2=”Cholera is a disease of muscles due to consumption of alcohol” option3=”Cholera is a disease due to consumption of contaminated food or water” option4=”Cholera is a genetic disease” correct=”option3″]

Cholera is a disease due to consumption of contaminated food or water.

Cholera is caused by the bacterium Vibrio cholerae, which is transmitted through the fecal-oral route.

Ingestion of water or food contaminated with the feces of an infected person is the primary mode of transmission. The bacterium produces a toxin that causes severe watery diarrhea, leading to rapid dehydration. It is not a genetic disease, nor primarily related to alcohol consumption or causing loss of memory.

Which one of the following statements regarding Penicillin is correct ?

[amp_mcq option1=”Penicillin resistant bacteria can store this antibiotic in vacuole” option2=”Penicillin resistant bacteria can degrade this antibiotic by an enzyme called β-lactamase” option3=”Penicillin resistant bacteria can degrade this antibiotic by an enzyme called lactic acid dehydrogenase” option4=”Penicillin is not absorbed by bacteria, so most bacteria are resistant” correct=”option2″]

Penicillin resistant bacteria can degrade this antibiotic by an enzyme called β-lactamase.

Beta-lactamase enzymes break the beta-lactam ring structure, which is essential for the activity of penicillin and related antibiotics.

Bacterial resistance to antibiotics, including penicillin, is a significant public health challenge. Different bacteria have evolved various mechanisms to resist antibiotics, with beta-lactamase production being one of the most common for resistance to penicillin.