An Organism That Appears Red with a Black Center on XLD

question 1

Multiple Choice

An organism that appears red with a black center on XLD agar is lactose-_____ and H₂S-_____.

• A)positive;positive
• B)positive;negative
• C)negative;positive
• D)negative;negative

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Definitions:

Cyanosis

A blue or purplish discoloration of the skin and mucous membranes due to deficient oxygenation of the blood.

Buccal Mucosa

The lining of the cheeks inside the mouth, consisting of a mucus membrane that is important for oral health and the administration of certain medications.

Dark-Skinned

Having a skin color that is richly pigmented, typically described for individuals with higher melanin content in the dermis.

Absorption

The process by which substances are taken up and incorporated into the body, as in nutrient absorption in the digestive tract.