Use the Following Information When Answering the Corresponding Questions)

question 2

Multiple Choice

Use the following information when answering the corresponding questions) .
It has been shown that there are two distinct variants of the HIV virus Bleul et al. 1997. The HIV coreceptors CXCR4 and CCR differentially regulated on human T- lymphocytes. Proceedings of the National Academy of Science 94:1925- 30) . One virus preferentially infects macrophages and is called M- tropic. The other preferentially infects T cells and is called T- tropic. The M- tropic viruses use CCR5 and CD4 as coreceptors, and the T- tropic viruses use CXCR4 and CD4 as coreceptors. The
M- tropic viruses are found early in HIV infections; the T- tropic viruses are found late in infections, when AIDS symptoms are prevalent. T- tropic viruses are associated with a drastic decrease in T cells. Macrophages go to the site of wounds, where they are used to fight infections. T cells circulate in the body and fight infections at many sites.
-Which receptors for HIV would you expect to find on macrophages and T cells?

• A) CXCR4 and CD4 on macrophages; CCR5 and CD4 on T cells
• B) CD4 and CXCR4 on macrophages; CXCR4 and CD4 on T cells
• C) CCR5 and CD4 on macrophages; CXCR4 and CD4 on T cells
• D) CCR5 and CXCR4 on macrophages; CD4 and CXCR4 on T cells

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Definitions:

Periodic Tenancy

A tenancy agreement that automatically renews for a fixed period, such as monthly or yearly, until notice is given to terminate it.

Tenancy from Month to Month

A rental agreement where the lease period is for one month, automatically renewing each month until either the landlord or tenant decides to terminate it.

Tenancy at Sufferance

A situation where a tenant remains in possession of property after the expiration of the lease, without the consent of the landlord but without being evicted.

Landlord's Rights

Legal rights afforded to landlords, including the right to collect rent, manage property, and evict tenants under certain conditions.