Lecture 7 Flashcards
regions of the gene that are coded
Exons
Non coding regions of the gene
introns
alternate form of a gene
spelling
Allele
Pathogenicity
Property of causing disease
Genes that are absolutly required to cause disease. aka the genes that make an organism a pathogen
spelling
Pathogenicity genes
Genes that are associated with degree of virulence/agressivness on host. eg genes that help pathogens to spread faster, more capable of causing disease
spelling
Virulence genes/virulence factors
what happens when there is a disruption of pathogenicity genes
complete loss of disease/significant reduction in disease in plants
How is the variability in sexually reproducing organisms
all progeny (decendents) are variable
How is the variability in asexually reproducing pathogens
reduced degree/intensity and frequenct of variability among decendents. But the quantity is great meaning a low frequency of variablity could still be quite significant
What causes variability in plant pathogens
12 kinds & spelling
- Mutation
- sexual recombination
- Gene & genotype flow
- genetic drift
- selection
- life cycle
- pathogen fitness
- heterokaryosis
- parasexuality
- vegetative incompatibility
- heteroploidy
- sexual-like processes in bacteria (conjugation, transformation, transduction)
what do you call a loss of pathogen virulence in culture (spelling)
attenuation
Further classification based on what host the pathogen attacks
spelling
- ” special forms” (formae speciales)
- “Varirties”
Further classifications of special forms
spelling
- races
- pathotypes
further classifications of race & pathotypes
spelling
- isolates
each individual spore in an isolate
spelling
- biotype
How do plants defend themselves agasint pathogen attack
5 main ways & spelling
- non-host resistance
- basal defence (preformed structureal & chemical defense)
- induced structureal defence
- induced biochemical defence
- detoxification of plant pathogen toxins
- other mechanisms
What are the types of mutations
5 & spell them
- Signle nucleotide polymorphism (SNP)
- structural variations (insertion/deletion)
- frameshift mutation
- excision of transposable elements (TEs)
- complete loss of an allele/gene (rare)