A Patient Appears in a Clinic Complaining of Irritability and Chronic

question 51

Multiple Choice

A patient appears in a clinic complaining of irritability and chronic sweatiness. He also has a lump in his neck near his larynx. Blood tests show he has low levels of thyroid-stimulating hormone (TSH) in his plasma. Which of the following is the most likely diagnosis?

• A) primary hypothyroidism
• B) an iodine-insufficient diet
• C) secondary hypothyroidism
• D) hyposecretion of TRH
• E) Graves' disease

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Definitions:

Wavelengths

The distance between successive crests of a wave, especially points in a sound wave or electromagnetic wave.

Trichromatic Theory

The trichromatic theory of color vision posits that the human eye has three types of receptors sensitive to red, green, and blue light, which combine to produce the perception of all colors.

Cones

Photoreceptor cells in the retina of the eye that function best in relatively bright light and enable the perception of color.

Feature Detector Cells

Neurons in the brain that respond to specific characteristics of a visual stimulus, such as angles or movement.