A "9 + 2" arrangement of microtubules is seen in  __________ .


a. archaeal flagella
b. bacterial flagella
c. eukaryotic flagella
d. all prokaryotic flagella

Verified step by step guidance

1. Understand the structure of microtubules in different types of flagella.
2. Recall that the '9 + 2' arrangement refers to a specific pattern of microtubules.
3. The '9 + 2' arrangement consists of nine doublet microtubules surrounding two central singlet microtubules.
4. Identify which type of flagella typically exhibits this '9 + 2' microtubule arrangement.
5. Consider the differences between prokaryotic and eukaryotic flagella structures.

Key Concepts

Microtubule Structure

Microtubules are cylindrical structures made of tubulin protein that play critical roles in cell shape, transport, and division. The '9 + 2' arrangement refers to a specific organization of microtubules found in eukaryotic flagella and cilia, where nine doublet microtubules surround a central pair of single microtubules, providing structural support and facilitating movement.

Flagella Types

Flagella are whip-like structures that enable motility in various organisms. Eukaryotic flagella, characterized by the '9 + 2' microtubule arrangement, differ from prokaryotic flagella, which are simpler structures made of the protein flagellin and do not have the same microtubule organization. Understanding these differences is crucial for identifying the correct answer to the question.

Eukaryotic vs. Prokaryotic Cells

Eukaryotic cells, which include plants, animals, and fungi, possess membrane-bound organelles and complex structures like flagella with a '9 + 2' arrangement. In contrast, prokaryotic cells, such as bacteria and archaea, lack these organelles and have simpler flagella structures. This distinction is essential for answering questions related to cellular structures and their functions.