Since Viruses Have No Active Methods of Entering Plant Cells,they

question 7

Multiple Choice

Since viruses have no active methods of entering plant cells,they must rely upon mechanically caused wounds,vegetative propagation of plants,grafting,seed,pollen,and being carried on the mouth parts of chewing insects.Tobacco mosaic virus is most commonly introduced into plants through small wounds caused by handling and by insects chewing on plant parts.What would prevent viruses from easily entering plant cells?

• A)The cell wall on the virus
• B)The plasma membrane on the plant
• C)The cell wall on the plant
• D)The plasma membrane on the virus
• E)The protein coat on the virus

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Definitions:

Purely Competitive Market

A market structure characterized by a large number of firms or sellers, each of which has a relatively small market share and sells a homogeneous product, with no single firm able to influence market price.

Average Fixed Cost

The fixed costs of production (costs that do not vary with the level of output) divided by the quantity of output produced.

Marginal Cost

The increase in total cost that arises when the quantity produced is incremented by one unit.

Profit-maximizing Rule

The principle that firms maximize their profits by producing at a level where marginal costs equal marginal revenues.