Neisseria is morphologically –
**Core Concept**
Neisseria species are gram-negative diplococci, characterized by their distinctive morphological appearance. This morphology is a key feature in identifying these bacteria, which are commonly associated with various infections, including meningitis and gonorrhea.
**Why the Correct Answer is Right**
The diplococci morphology of Neisseria species is due to their unique cell arrangement, where two cocci are joined together, resembling a pair of coffee beans. This characteristic is a result of the bacteria's ability to adhere to epithelial cells and form pairs. The gram-negative staining of Neisseria species is also notable, as it lacks a peptidoglycan layer in its cell wall, which is a key component of gram-positive bacteria.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the morphology of Neisseria species. While some bacteria may exhibit a similar morphology, the diplococci arrangement is unique to Neisseria.
**Option B:** This option is incorrect because it is too general and does not specifically describe the morphology of Neisseria species. Many bacteria can be described as cocci, but the diplococci arrangement is a distinctive feature of Neisseria.
**Option C:** This option is incorrect because it contradicts the established morphology of Neisseria species. While some bacteria may exhibit a similar morphology, the diplococci arrangement is a key feature of Neisseria.
**Clinical Pearl / High-Yield Fact**
It's essential to note that the morphology of Neisseria species can be altered by various factors, such as culture conditions and staining techniques. However, the diplococci arrangement remains a reliable indicator of Neisseria infection.
**Correct Answer:** D.