Maintaining Homeostasis

By Ashley Benhayoun; GT Bio Mcdowell Period 7

How Bacteria and Viruses Maintain Homeostasis

How do viruses maintain homeostasis?

Viruses DO NOT go through have homeostasis. They go through no cellular activities since they are not made of cells. This means that they do not move or grow.
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Flu virus

How do bacteria maintain homeostasis?

Bacteria can adjust to changing environmental conditions that surround them. Bacteria go through different homeostatic processes that help bacteria survive.

Types of Bacteria Homeostasis

Iron Homeostasis

Iron is necessary for bacteria, but high amounts of it can be toxic. Bacteria can go through this process even in environments low in iron. In iron homeostasis, some bacteria can used special proteins which maximize the amount of iron that can be taken in. Bacteria capable of causing disease in human blood can go maintain iron homeostasis by using the host’s iron complexes. Bacteria has proteins which are used to store iron as a reserve located inside the cell. When bacteria are in environments that have very high and toxic levels of iron, they can use detoxification proteins which protect their chromosome from damage.

Metal Homeostasis

Iron isn’t the only element that bacteria can sense. Other metals include lead, cadmium and mercury. Metal sensors in bacteria (some) can sense and regulate toxic heavy metals and beneficial metal ions that are in the cell. For example, Mycobacterium tuberculosis has more than ten metal sensors.

Ph Homeostasis

Most bacteria species can handle pH levels near neutral (7), but bacteria nicknamed extremophiles can live in environments with pH levels below 3 and above 11. Bacteria have several mechanisms that sense external changes in ph levels. There are numerous adaptations that contribute to pH homeostasis. This includes high levels of transporters and enzymes ,metabolic changes that lead to increased acid production, and changes in the cell surface layers that contribute to proton retention. The pH homeostasis of most bacteria give them the ability to tolerate different external levels of pH.

Membrane Lipid Homeostasis

Bacteria can change the lipid or fat composition of their cell membranes which changes the cell’s permeability. They do this by modifying the types of fatty acids that are produced and changing the structures of existing phospholipids. This ability to control the amount of lipid in their membranes (called membrane lipid homeostasis) makes them able to survive in an array of environments.
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E. Coli Bacterium