A 9-Month-Old Boy Is Brought to the Clinic for a Routine

question 39

Multiple Choice

A 9-month-old boy is brought to the clinic for a routine follow-up.  His mother is concerned because the patient is not yet able to sit up unsupported.  He was born at term and has had muscle weakness since birth.  Vital signs are normal.  The patient is alert but has diminished tone.  Examination shows a prominent forehead with a depressed nasal bridge.  Eye examination shows epicanthal folds.  Analysis of lysosomal acid hydrolases shows an increased concentration within the serum and a decreased level within the cultured skin fibroblast cells.  This patient most likely has a defect in which of the following steps of enzyme production?

• A)DNA methylation
• B)Posttranslational modification
• C)Protein folding
• D)Splicing
• E)Translation

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Definitions:

Fixed Costs

Costs that remain constant regardless of the amount of products or services a company generates, including expenses like lease payments, wages, and premiums.

Break-even Point

The volume of production or sales at which total revenues equal total costs, resulting in neither profit nor loss.

Variable Cost

Expenses that vary directly with the level of production or sales volume, such as raw materials and direct labor.

Margin of Safety

The difference between actual or projected sales and the break-even point, indicating the amount by which sales can drop before reaching a loss.