Multiple Choice
Eukaryotic cilia & flagella are made of:
666
views
4
rank
8. Eukaryotic Cell Structures & Functions
Eukaryotic Cilia & Flagella
2:09 minutesProblem 3
Textbook Question
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 guidance1
Understand that the '9 + 2' arrangement refers to the specific structural pattern of microtubules found in certain flagella or cilia, where 9 pairs of microtubules form a ring around 2 central single microtubules.
Recall that microtubules are components of the cytoskeleton made of tubulin proteins, and this '9 + 2' pattern is characteristic of eukaryotic cells, not prokaryotic cells.
Recognize that prokaryotic flagella (found in bacteria and archaea) do not have microtubules; instead, they are composed of the protein flagellin and have a different structural organization.
Therefore, identify that the '9 + 2' microtubule arrangement is specifically seen in eukaryotic flagella and cilia, which are membrane-bound organelles.
Conclude that the correct answer corresponds to the option describing eukaryotic flagella.
Verified video answer for a similar problem:This video solution was recommended by our tutors as helpful for the problem above
Video duration:
2mKey Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Structure of Microtubules in Flagella
The '9 + 2' arrangement refers to a specific microtubule pattern found in the axoneme of eukaryotic flagella and cilia, consisting of nine doublet microtubules surrounding two central singlet microtubules. This structure is essential for the motility of eukaryotic cells.
Recommended video:
Guided course
02:53
Prokaryotic Flagellar Structure
Differences Between Prokaryotic and Eukaryotic Flagella
Prokaryotic flagella, found in bacteria and archaea, are structurally simpler and made of flagellin protein, lacking microtubules. In contrast, eukaryotic flagella have a complex internal structure with microtubules arranged in the '9 + 2' pattern, powered by dynein motor proteins.
Recommended video:
Guided course
02:07Introduction to Prokaryotic Flagella
Function and Composition of Eukaryotic Flagella
Eukaryotic flagella are membrane-bound organelles that enable cell movement through coordinated bending of microtubules. Their '9 + 2' microtubule arrangement provides structural support and facilitates movement via ATP-driven dynein arms.
Recommended video:
Guided course
02:36Eukaryotic Cilia & Flagella
Related Videos
Related Practice