A 2-Year-Old Boy Is Being Evaluated at the Office for Failure

question 89

Multiple Choice

A 2-year-old boy is being evaluated at the office for failure to thrive and developmental delay.  Medical history is significant for recurrent ear infections since 6 months of age.  Physical examination shows corneal clouding, hepatosplenomegaly, and restricted joint mobility.  Further evaluation shows deficient phosphorylation of mannose residues on certain glycoproteins in the Golgi apparatus.  In unaffected patients, these proteins are normally transported to which of the following cellular locations?

• A)Endoplasmic reticulum
• B)Extracellular space
• C)Lysosome
• D)Mitochondria
• E)Plasma membrane

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Definitions:

Ringing

A condition often described as hearing a continuous sound (such as ringing, buzzing, or hissing) in the ears when no external sound is present, known as tinnitus.

Hearing Loss

The partial or total inability to hear sound in one or both ears.

Aging

The process of becoming older, a physiological process that leads to changes in the body over time, including decline in function and increased risk of diseases.

Decibels

A unit of measurement for the intensity of sound, indicating the level of volume.