WT Yeast (TRP+)can Synthesize the Amino Acid Tryptophan and Can

question 38

Multiple Choice

WT yeast (TRP+) can synthesize the amino acid tryptophan and can grow on media plates lacking tryptophan. In contrast, mutant alleles (trp-) block tryptophan synthesis and result in an inability of mutant strains to grow on media lacking tryptophan. A diploid yeast was made through the cross MATa ADE+ × MATα ade-. Meiosis was induced in the diploid strain to produce an ascus with four haploid spores, which were separated and grown on plates lacking tryptophan. How many spores are expected to grow into colonies on the plate?

• A)0
• B)1
• C)2
• D)3
• E)4

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Definitions:

Positive Economic Profits

The situation in which a firm's total revenues exceed its total costs, including both explicit and implicit costs, signaling that the firm is doing better than the next best alternative.

Profit

The financial gain realized when the amount earned from a business activity exceeds the expenses, costs, and taxes needed to sustain the activity.

Monopolistically Competitive Firm

A company that operates in a market with many competitors, each offering products that are similar but not identical, allowing for some degree of market power.

Price Higher Than Marginal Cost

A situation where the selling price of a product is set above the marginal cost of production, often leading to increased profitability but potentially distorting market efficiency.