Which of the following is true about food-borne infections? A. Requires the grow

Question

Which of the following is true about food-borne infections?
A. Requires the growth of the organism prior to illness.
B. Only associated with fungal-mediated contamination.
C. Symptoms typically occur shortly (within hours) after ingestion of the food
D. Both A and C.

3. Which of the following must be performed to allow for the expression of eukaryotic genes in bacterial cells?
A. Introduction of eukaryotic replication machinery into the bacteria
B. Removal of exons of the eukaryotic DNA via restriction enzymes
C. Use of reverse transcriptase to convert eukaryotic mRNA into DNA.
D. A and C

Explanation / Answer

For food-borne infections, option (C) is correct which states that symptoms occur shortly (within hours) after ingestion of the food.

In food born infection, food is merely the vector for microbes that do not grow on their transient substrate. For instance,  foodborne infections occur when food, that is contaminated with bacteria, is eaten and the bacteria continues to grow in the intestines, setting up an infection which causes illness (option A, B and D incorrect).

For allowing the expression of eukaryotic genes in bacterial cells: option C will be required. Introduction of eukaryotic replication machinery into the bacteria is not required since reverse transcriptase can be used to convert eukaryotic mRNA to DNA which is transmitted into the bacterial cell using a plamid vector. Therefore, option (A) is not required as a plasmid vetcor is used.

Example for this includes : Insertion of eukaryotic mRNA for insulin production along with reverse transcriptase into bacteria or the mRNA could be inserted into the prokaryote's genome. Large amounts of insulin can then be created. Directly inserting eukaryotic DNA into bacteria would not work because it carries introns, so would not translate successfully using the bacterial ribosomes. Processing in the eukaryotic cell during mRNA production removes these introns to provide a suitable template. Reverse transcriptase converts this edited RNA back into DNA so that it gets incorporated in the genome.

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.