Q.) `"______"` is a couple of layer thick, made of narrow, thin walled and nearly rectangular cells. It cuts dervatives on both sides. The outer cells differentiate into `"_____"` or `"______"` while the inner cells differentiate into `"______"` or `"_______"`. The three together is called `"_______"`
Select the right sequence of words to complete the above given paragraph.

Options

A. a) Phellogen, cork, phellem, secondary cortex, phelloderm, periderm
B. b) Phellem, phelloderm, cork, secondary cortex, phellogen, periderm
C. c) Phellogen, cork, periderm, secondary cortex, phellem, phelloderm
D. d) Phellem, secondary cortex, periderm, cork, phellogen, phelloderm

Answer

To solve the fill-in-the-blank question, we need to identify the correct terms that fit into the provided statements based on our knowledge of plant anatomy, particularly the structures involved in the formation of periderm.

### Step-by-Step Solution:

1. **Identify the structure described**: The question begins with a description of a structure that is "a couple of layers thick, made of narrow, thin-walled and nearly rectangular cells." This description fits the **"phallogen,"** which is a type of meristematic tissue responsible for producing the outer protective layers of plants.

**Hint**: Think about the type of tissue that forms protective layers in plants.

2. **Determine what the outer cells differentiate into**: The outer cells of the phallogen differentiate into **"cork."** Cork is a protective tissue that forms the outer bark of trees.

**Hint**: Consider what protective layer is formed on the outside of a plant.

3. **Determine what the inner cells differentiate into**: The inner cells of the phallogen differentiate into **"phallum"** or **"secondary cortex."** Both terms refer to the tissues that lie beneath the cork layer.

**Hint**: Think about the tissues that provide support and storage beneath the outer protective layer.

4. **Identify the overall term for the three layers**: The three layers together (phallogen, cork, and phallum/secondary cortex) are collectively known as **"periderm."** The periderm is the protective tissue that replaces the epidermis in plants as they grow.

**Hint**: What is the term used to describe the outer protective layer of a plant that includes multiple tissues?

### Final Answer:
The correct sequence to complete the paragraph is:
**"phallogen" is a couple of layers thick, made of narrow, thin-walled and nearly rectangular cells. It cuts derivatives on both sides. The outer cells differentiate into "cork" while the inner cells differentiate into "phallum" or "secondary cortex." The three together is called "periderm."**

### Selected Option:
The correct option is **A: phallogen, cork, phallum, secondary cortex, phalloderm, periderm.**