Phospholipids Make Up Most of the Lipid Part of the Cell

question 68

Multiple Choice

Phospholipids make up most of the lipid part of the cell membrane. Since water exists on both the outside and inside of a cell, which of the following phospholipid arrangements makes the most sense?

• A) two back-to-back phospholipid layers with the polar heads facing out on both sides
• B) a single layer of phospholipids with the polar heads facing outside the cell
• C) a single layer of phospholipids with the polar heads facing inside the cell
• D) two back-to-back phospholipid layers with the non-polar tails facing out on both sides

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Definitions:

Opportunity Costs

The loss of potential gain from other alternatives when one alternative is chosen.

Carrying Costs

Expenses associated with holding inventory, including storage, insurance, and obsolescence costs, among others.

Net Present Value

Net Present Value (NPV) is a financial metric used to evaluate the profitability of an investment, calculating the difference between the present value of cash inflows and outflows over a period of time.

Variable Cost

Costs that vary directly with the level of production or service volume, such as raw materials and direct labor expenses.