Influenza Strains That Sweep Around the World Often Carry Names

question 75

Multiple Choice

Influenza strains that sweep around the world often carry names such as Shanghai H₁N₁ or Mexico City H₂N₂.The viruses vary in H and N surface spikes because

• A) the viruses reproduce on their own and attack people in cities more often.
• B) these viruses emerged as stray DNA from the genomes of people in these cities.
• C) this is where the antibodies of immune people began to break down and the old virus was again virulent.
• D) infected people develop immunity to the present strain, and strains that mutate sufficiently to be outside the range of immunity are soon spread in highly populated areas.
• E) the H and N surface spikes are obtained from the human hosts.

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Definitions:

Accounts Receivable Turnover

A financial ratio that measures how efficiently a company collects revenue from its credit sales, calculated by dividing net credit sales by the average accounts receivable.

Net Credit Sales

The total value of sales made on credit during a period, minus any sales returns or allowances.

Accounts Receivable

Outstanding payments from clients or customers to a company for delivered goods or services that remain unpaid.

Factoring Transaction

The process where a business sells its accounts receivable (invoices) to a third party (factor) at a discount, in exchange for immediate cash.