1. Biofilms can form on medical implants within human tissues.
2. Biofilms can form on food and food processing surfaces.
3. Biofilms can exhibit antibiotic resistance.

Which of the statements given above are correct?

(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3

Ans: d

Explanation:

Bacteria often attach to surfaces and form dense aggregations called biofilms or bacterial mats. These films can range from a few micrometers in thickness to up to half a meter in depth, and may contain multiple species of bacteria, protists, and achaea. 

Bacteria living in biofilms display a complex arrangement of cells and extracellular components, forming secondary structures such as microcolonies through which there are networks of channels to enable better diffusion of nutrients. 

In natural environments, such as soil or the surfaces of plants, most bacteria are bound to surfaces in biofilms. 

Biofilms are also important in medicine, as these structures are often present during chronic bacterial infections or in infections of implanted medical devices, and bacteria protected within biofilms are much harder to kill than individual isolated bacteria. Even more complex morphological changes are sometimes possible.

Hence, statement 1 is correct.

Biofilms is technically bacteria and exhibits all characteristics of bacteria including attaching to the food surfaces and antibiotic resistance.

Hence, statements 2 and 3 are correct.

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