Phytoalexins are low molecular weight, lipophilic antimicrobial compounds for which phenylalanine is a substrate used by phenylalanine ammonia lyase (PAL),

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#Unit 4. Cell Communication and Cell Signaling

Malaria (Parasitic)

Sporozoites enter the bloodstream by mosquito.

The sporozoites migrate to the liver, where they multiply, transforming liver hepatocytes into giant multinucleate schizonts, which release thousands of merozoites into the bloodstream. 

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#Unit 4. Cell Communication and Cell Signaling

The merozoites infect red blood cells, which eventually rupture, releasing more merozoites. 

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#Unit 4. Cell Communication and Cell Signaling

Eventually some of the merozoites differentiate into male and female gametocytes, which are ingested by a mosquito and differentiate into gametes in the mosquito’s gut. 

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#Unit 4. Cell Communication and Cell Signaling

The gametes fuse to form a zygote that differentiates to the sporozoite stage within the salivary gland of the mosquito.

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#Unit 4. Cell Communication and Cell Signaling

Leishmaniasis

Leishmania is a flagellated protozoan that lives in the phagosomes of macrophages and is transmitted by sand flies.

TLS Online TPP Program

#Id: 9949

#Unit 4. Cell Communication and Cell Signaling

Resistance to leishmaniasis correlates well with the production of IFN-ϒ and the development of a TH1 response.

Strains of mice that are naturally resistant to Leishmania develop a TH1 response and produce IFN-ϒ upon infection.