The Right Heart Shadow Is Not Visible on Your Patient's

question 35

Multiple Choice

The right heart shadow is not visible on your patient's chest radiograph. Which of the following pathologies may explain this?

• A) Right middle lobe pneumonia
• B) Right lung pneumothorax
• C) Bilateral emphysema
• D) Bleb in the right lower lobe

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Definitions:

X Chromosome Inactivation

A process by which one of the copies of the X chromosome present in female mammals is inactivated, ensuring that males and females have the same dose of the X chromosome genes.

X Chromosome Inactivation Center (XIC)

A critical region on the X chromosome that controls the process of X chromosome inactivation during female development.

Codominance

A genetic scenario where two alleles of a gene pair in a heterozygote are fully expressed, resulting in offspring with a phenotype that is neither dominant nor recessive.

Phenotypes

The observable physical or biochemical characteristics of an organism, determined by both genetic makeup and environmental influences.