Bacteria

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BACTERIA

Period: 4

Characteristics:

3 major shapes
Cocci Basilli Spirilla

3 major components

Mesosomes flagella

Plasmids

Growing Up:

Bacteria can obtain energy through phototrophs(sunlight), lithotrophs(inorganic compounds), and organotrophs(organic compounds)

Marriage/Reproduction

Binary Fission: The process by which all bacteria reproduce. It results in the separation of a single cell into two.

Transformation: genetic alteration of a cell resulting from the direct uptake, incorporation and expression of exogenous genetic material (exogenous DNA) from its surroundings and taken up through the cell membrane(s). Transformation occurs naturally in some species of bacteria, but it can also be affected by artificial means in other cells.

Conjugation: The process whereby two ciliates come together in a temporary fusion to exchange micro nuclear material, then separate, each being a fertilized cell.

 Explain how the F plasmid controls conjugation in bacteria. In bacterial conjugation the host bacterium attaches to another bacterium via pili. The plasmid region contains its own origin of replication in other words it can replicate independently from the DNA that is in the cytoplasm. This DNA tends to code for virulence factors. When the pili has attached to the recipient cell then DNA replication of the F-plasmid occurs and it is transferred over to the recipient cell making the recipient cell now an F+ cell. However, these cells can't perform this process with other F- cells because this type of cell lacks the pili to perform conjugation. 

Explain how bacterial conjugation differs from sexual reproduction in eukaryotic organisms. In bacterial conjugation, a bacterium forms a sex pilus and uses that to inject a copy of a plasmid into another bacterium. The recipient cell isn't "haploid" for the genes on this plasmid. It may or may not already have copies of the plasmid. It doesn't become...
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