Concept explainers
Describe why a microbial mat has green, reddish-pink, and black layers.
To review:
The microbial mat having green, reddish-pink, and black layers.
Introduction:
Biofilm is a thin layer or sheet, which is composed of living organisms such as microbes that are attached to the surfaces of solids or in between the air and water faces. A microbial mat is a dense, multilayered, thick, and highly organized form of a biofilm, which is composed of colonies of mainly archaea and bacteria. These mats provide an important model for the study of microbial interactions and microbial communities.
Explanation of Solution
The microbial mats consist of several layers that are visually distinguishable. There are mainly three colored layers, which represents the growth of different microbial communities. The green colored layer is the topmost layer that consists of mainly cyanobacterial community and appears green due to the presence of green photosynthetic pigments in them and makes the organic materials. Below this, is the pink-colored layer that represents the community of purple sulfur bacteria. These are anaerobic phototrophs. The lowermost layer is black in color, which represents the community of sulfate-reducers. These are obligate anaerobic bacteria that metabolize the organic components synthesized by the upper layers of the microbial mat.
Therefore, the microbial mat represents the distinct layers of the microbial communities that are present altogether. The uppermost layer is green due to the cyanobacterial community, the pink-colored one is present in middle comprising of purple sulfur bacteria and the lowermost is black in color showing the sulfate-reducing bacteria.
Want to see more full solutions like this?
Chapter 28 Solutions
Nester's Microbiology: A Human Perspective
- Diseases that involve biofilm-producing bacteria are serious concern. They are not easily treated compared with those involving free-floating bacteria. Explain three reasons why biofilm formers are more pathogenic.arrow_forwardDescribe a microbial biofilm. Discuss why it is likely that a biofilm contains bacteria with different energy metabolisms?arrow_forwardCategorise the microbial growth into four phases. In your own words, briefly describe each of themarrow_forward
- Biofilms represent an important environmental niche. A) How does growth on a surface differ from growth in a suspended laboratory culture? (In other words: How do biofilm-forming cultures differ from planktonic cultures) B) Describe the stages of biofilm development including cellular and extracellular components?arrow_forwardWhy are infections that involve biofilms a concern?arrow_forwardWhich of the following is NOT true about endospores? O 1) Spores are resistant to heat, radiation, cold, and dessication. O 2) One endospore germinates into one vegetative cell. O 3) They are a method of reproduction for bacterial cells when growth conditions are inhospitable. O 4) Endospores are clinically significant in causing disease. O 5) The endospore has a thick spore coat that protects it.arrow_forward
- Biofilms represent an important environmental niche. A) How does growth on a surface differ from growth in a suspended laboratory culture? (In other words: How do biofilm-forming cultures differ from planktonic cultures) B) Describe the stages of biofilm development including cellular and extracellular components? C) What processes regulate might regulate biofilm formation? Is quorum sensing involved and if so, how common is it? D) Why would biofilms promote the formation of genetic variants? What are the mechanisms by which this might occur? These questions are all related.arrow_forwardWould all microorganisms exhibit the same bacterial growth curve? Why?arrow_forwardDescribe a detrimental and a beneficial effect of biofilms.arrow_forward
- Which of the following is correct about biofilms? O 1) They are comprised only of psychrophiles. O 2) They are more sensitive to changes in growth conditions than planktonic cells O 3) Quorum sensing allows the biofilm community to behave differently than planktonic organisms 4) Biofilms only form within the environment. 5) Pure cultures are necessary for biofilm formation.arrow_forwardIn microbiology, the term growth in a culture usually refers to an increase in O 1) the number and size of microbial cells. O 2) the amount of ATP consumed. O 3) a microbe's size. O 4) the number of microbial cells. 5) the amount of ATP produced.arrow_forwardWhy might clinical medicine have an interest in understanding bacterial cell division at the molecular level? Explain why a hyperthermophile would probably not be a human pathogen. Describe four factors that may have an influence on the effectiveness of an antimicrobial treatment. Explain why 70% or 80% alcohol is more effective than 100% alcohol in controlling microorganisms.arrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education