Find incorrect statement with regard to centrosome and centrioles :-
(a) Centrosomes are surrounded by amorphous pericentriolar material
(b) In centrosome, bothe centrioles lie parallel to each other in which each has an organisation like the cartwheel
( c ) Centrioles are made up of nine unevenly spaced peripheral fibrils of tubulin
(d) Hub is the central proteinaceous part of centriole
( e )Proteinaceous radial spokes connect hub to peripheral triplets

Options

A. a,b, e
B. only b
C. b, c
D. All are correct

Answer

To find the incorrect statement regarding centrosomes and centrioles, we will analyze each option provided in the question:

1. **Statement (a)**: "Centrosomes are surrounded by amorphous pericentriolar material."
- This statement is **correct**. Centrosomes are indeed surrounded by a dense, amorphous pericentriolar material that helps in microtubule organization.

2. **Statement (b)**: "In centrosome, both centrioles lie parallel to each other in which each has an organization like the cartwheel."
- This statement is **incorrect**. In a centrosome, the two centrioles are arranged perpendicular to each other, not parallel. The cartwheel structure is characteristic of each centriole, but their orientation is perpendicular.

3. **Statement (c)**: "Centrioles are made up of nine unevenly spaced peripheral fibrils of tubulin."
- This statement is **incorrect**. Centrioles are actually composed of nine triplets of microtubules arranged in a cylindrical structure. The term "unevenly spaced" is misleading, as the triplets are evenly spaced around the centriole.

4. **Statement (d)**: "Hub is the central proteinaceous part of centriole."
- This statement is **correct**. The hub is indeed the central part of the centriole, which connects the peripheral microtubule triplets.

5. **Statement (e)**: "Proteinaceous radial spokes connect hub to peripheral triplets."
- This statement is also **correct**. Radial spokes are protein structures that connect the central hub to the peripheral triplets of microtubules in the centriole.

### Summary of Incorrect Statements:
The incorrect statements are **(b)** and **(c)**.

### Final Answer:
**Incorrect statements regarding centrosome and centrioles are (b) and (c).**

---