Consider the Pathway for the Synthesis of the Amino Acid

question 40

Multiple Choice

Consider the pathway for the synthesis of the amino acid arginine in Neurospora: $\begin{array}{c}\text { ornithine } \stackrel{\text { ARG-E }}{\rightarrow} \text { citrulline } \stackrel{\text { ARG-F }}{\rightarrow} \text { argininosuccinate } \stackrel{\text { ARG-H }}{\rightarrow} \text { arginine }\end{array}$
Mutant strains of Neurospora are grown in minimal media supplements as follows.The strains may carry more than one mutation.Growth is shown by (+) and no growth is shown by (o) . $\begin{array}{cccccc}&&&\text { Supplements }\\\text { mutant } & \text { nothing } & \text { ornithine } & \text { citrulline }&\text { arginino- } & \text { arginine } \\\text { strain } & &&&{\text { succinate }} \\\mathrm{a} & 0 & 0 & 0 & + & + \\\mathrm{b} & 0 & 0 & + & + & +\end{array}$
Strain a accumulates citrulline,strain b does not.Indicate the statement that is most correct regarding these two strains.

• A) Strain a has a mutation in ARG-E only.
• B) Strain b has only one mutation.
• C) Strain a has mutations in ARG-F and ARG-H.
• D) Strain a has mutations in ARG-E,ARG-F and ARG-H.
• E) Strain a has a mutation in ARG-H only.

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Definitions:

Demand Curve

A graph showing the relationship between the price of a good and the quantity demanded at those prices, typically downward sloping.

Demand

The quantity of a good or service that consumers are willing and able to purchase at various prices during a specified period.

Shifts

Refers to changes in the position of demand or supply curves in economic models, often due to changes in external factors such as technology, preferences, or policy.

Demand Curve

A graphical representation showing the relationship between the price of a good or service and the quantity of that good or service that consumers are willing and able to purchase at various prices.