Problem
I. Identify the 3 Domains of life, and briefly describe at least 2 unique structural or chemical features of each Domain (something that isn't found in the other Domains-?
This is the answer for number please change the word to your own words please? not same as bottom?
i. Bacteria: lack membrane -bound organelles, like a nucleus (they are prokaryotes), and can function and reproduce as individual cells, but often aggregate in multicellular colonies. Bacteria are surrounded by a cell wall, composed of peptidoglycan, which provides strength and rigidity to their cells and is unique to this Domain. Most bacterial species are harmless and play important ecosystem roles, but some members are pathogenic and cause disease. Bacteria do have a single circular chromosome for its entire genome, and contains unique rRNA sequences that justify it being a separate Domain from Archaea.
ii. Archaea: In the past, the differences between bacteria and archaea were not recognized and archaea were classified with bacteria as part of the kingdom Monera. Archaea are also single-celled organisms that lack nuclei. Archaea in fact differ from bacteria in both their genetics and biochemistry. While bacterial cell membranes are made from phospholipids with ester bonds between glycerol and fatty acid chains, Archaean membranes are made using ether bonds to phytanyl (isoprene based) chains.. Another major distinguishing feature of Archaeans is that some do not have cell walls, but those that do have cell walls completely lack peptidoglycan, and use either pseudopeptidoglycan or S-layer proteins or may lack a cell wall altogether. Yet another difference between Archaea and the other Domains is that none of its members are pathogens or parasitic to any other forms of life (that we know of yet). Archaeans are prokaryotes (like Bacteria) but they have distinct rRNA sequences (16S rRNA) from that seen in Bacteria.
iii. Eukarya: Unlike bacteria and archaea, eukaryotes contain organelles such as the cell nucleus, the Golgi apparatus, and mitochondria in their cells. Like bacteria, plant cells have cell walls (but made of cellulose, not peptidoglycan) and contain organelles such as chloroplasts in addition to the organelles in other eukaryotes. Fungi, which are also eukaryotes, have cell walls made of chitin. Eukarya does have some species that are unicellular, but it is the only Domain that possesses true multicellular organisms.
II. What are antibodies (what type of molecule?) and how do they work to stop antigens? (hint: there are 3 ways antibodies stop antigens)?
i. Neutralization-
ii. Agglutination-
iii. Antibody-Dependent Cell-mediated Cytotoxicity (ADCC)-
III. Identify and describe the 3 main modes of transmission for communicable diseases. Provide an example of a pathogen that is transmitted by each mode with your answer (0.67pts/example)?
This is the answer for number 3 please change the word to your own words ? not same as bottom?
Understanding how infectious pathogens spread is critical to preventing infectious disease. All diseases can be grouped into 3 main transmission types:
i. Contact transmission includes direct contact or indirect contact. Person-to-person transmission is a form of direct contact transmission. Here the agent is transmitted by physical contact between two individuals through actions such as touching, kissing, sexual intercourse, or droplet sprays. Indirect contact transmission involves inanimate objects called fomites that become contaminated by pathogens from an infected individual or reservoir (such as someone touching a doorknobs after sneezing into their hand). An example of a pathogen that spreads through contact is Influenza or the Common Cold (Adenoviruses, Rhinoviruses)
ii. The term vehicle transmission refers to the transmission of pathogens through vehicles such as water, food, and air. Water contamination through poor sanitation methods leads to waterborne transmission of disease. Similarly, food contaminated through poor handling or storage can lead to foodborne transmission of disease. An example of a pathogen that is airborne is smallpox, a waterborne pathogen is Vibrio cholerae, and a food borne pathogen is Salmonella enteritidis.
iii. Diseases can also be transmitted by a mechanical or biological vector, an animal (typically an arthropod) that carries the disease from one host to another. Mechanical transmission is facilitated by a mechanical vector, an animal that carries a pathogen from one host to another without being infected itself. Biological transmission occurs when the pathogen reproduces within a biological vector that transmits the pathogen from one host to another. For example, Ixodes ticks transmit Borrelia burgdorferi (Lyme's Disease) to humans when they bite to draw a blood meal.
IV. Identify the 3 major modes of transmission for communicable diseases. Describe how each mode works and provide an example of a pathogen that is transmitted by each mode.
V. What is "antibiotic resistance"? Provide at least 2 examples of actions we can each take to help reduce or slow this problem down.