Why Are Two Children Born to the Same Parents (Not

question 41

Multiple Choice

Why are two children born to the same parents (not identical twins) unlikely to have the same genetic makeup?

• A) Crossing-over recombines portions of sister chromatids.
• B) Fertilization provides a new pairing of chromosomes.
• C) Each sperm or egg has a random assortment of chromosomes, half from each pair.
• D) Chromosomes align themselves independently during meiosis I.
• E) All of the answer choices lead to genetic differences among siblings.

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Definitions:

Marginal Product

The extra output or benefit received from using one additional unit of a resource.

Opportunity Cost

The cost of an alternative that must be forgone in order to pursue a certain action, the benefits you could have received by taking an alternative action.

Marginal Cost

The cost added by producing one more item of a product, a crucial factor in economic decision-making regarding production levels.

Economic Profit

The difference between a firm’s total revenues and its total costs, including both explicit and implicit costs, representing the actual financial gain.