The Secondary Signal Needed from a T Cell for a B

question 31

Multiple Choice

The secondary signal needed from a T cell for a B cell to differentiate into a plasma cell is the crosslink between:

• A) CD8 (on the T_C cell) with MHC I (on the B cell)
• B) CD4 (on the T_H cell) with CD40 (on the B cell)
• C) MHC II (on the T_C cell) with CD4 (on the B cell)
• D) CD8 (on the T_C cell) with CD40 (on the B cell)
• E) CD154 (on the T_H cell) with CD40 (on the B cell)

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Definitions:

Discount Rate

The interest rate used in discounted cash flow (DCF) analysis to determine the present value of future cash flows, reflecting the risk and time value of money.

Initial Cost

The total expense incurred to acquire an asset or start a project, including purchase price and all associated fees.

Accounting Break-even

The point at which total costs and total revenues are equal, leading to neither profit nor loss.

Variable Costs

Costs that vary directly with the level of output or production, such as materials and labor.