Concept explainers
To explain: The number of the Ty2 strain of Salmonella typhi that was able to enter normal cells (those heterozygous for the normal allele) than cells heterozygous for the ΔF508 allele.
Concept introduction: Allele is the modification of the gene. Salmonella typhi is the causative bacteria of typhoid. Cystic fibrosis (CF) is a genetic disorder due to the inability of the cell to perform endocytosis due to the mutation in the CFTR gene. Cystic fibrosis affects the lungs, intestine, liver, and kidneys. Endocytosis is a phenomenon where the cell takes up the molecules by engulfing with its membrane. The S. typhi exploits this mechanism to infect the intestinal cell and causes diarrhea. The cells that are homozygous for this CFTR mutation cannot perform endocytosis and the S. typhi cannot infect those individuals.
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