Fill in the blanks :
1 . Centrioles are …a… structures that lie …b… to each other
2 . Centrioles have an organisation like …c…
3 . Centrioles are made up of nine evenly spaced peripheral fibrils of …d… protein
4 . Each peripheral fibril of centriole is ...e...
5 . Central part of the proximal region of the centriole is called ...f... which is proteinaceous

Options

A. a`-`spherical, b`-`parallel, c`-`cart wheel, d`-`flagellin , e`-`doublet, f`-`bridge
B. a`-`cylindrical, b`-`perpendicular, c`-`cart wheel, d`-`tubulin, e`-`triplet, f`-`hub
C. a`-`cylindrical, b`-`perpendicular, c`-`cart wheel, d`-`tubulin, e`-`triplet, f`-`hub
D. a`-`spherical , b`-`perpendicular, c`-`cart wheel, d`-`tubulin, e`-`triplet, f`-`hub

Explanation

### Step-by-Step Text Solution:

1. **Centriole Structure**: Centrioles are **cylindrical** structures that lie **perpendicular** to each other.
- **Answer**: a. cylindrical, b. perpendicular

2. **Organization of Centrioles**: Centrioles have an organization like a **cartwheel**.
- **Answer**: c. cartwheel

3. **Composition of Centrioles**: Centrioles are made up of nine evenly spaced peripheral fibrils of **tubulin** protein.
- **Answer**: d. tubulin

4. **Fibril Structure**: Each peripheral fibril of the centriole is **triplet**.
- **Answer**: e. triplet

5. **Central Part of Centrioles**: The central part of the proximal region of the centriole is called the **hub**, which is proteinaceous.
- **Answer**: f. hub

### Complete Answers:
1. Centrioles are **cylindrical** structures that lie **perpendicular** to each other.
2. Centrioles have an organization like a **cartwheel**.
3. Centrioles are made up of nine evenly spaced peripheral fibrils of **tubulin** protein.
4. Each peripheral fibril of the centriole is **triplet**.
5. The central part of the proximal region of the centriole is called the **hub**.

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