Phellogen and phellem respectively denote

Options

A. cork and cork cambium
B. cork cabium and cork
C. secondary cortex and cork
D. cork and secondary cortex

Explanation

To answer the question regarding what Phellogen and Phellem denote, we can follow these steps:

### Step 1: Understanding the Terms
- **Phellogen**: This is a type of meristematic tissue found in the stems of dicotyledonous plants. It is also known as cork cambium.
- **Phellem**: This is the tissue produced by the phellogen on one side. It is commonly referred to as cork.

### Step 2: Identifying Their Functions
- **Phellogen (Cork Cambium)**: The primary function of phellogen is to produce protective tissues. It forms a layer of cells that can divide and contribute to the outer protective covering of the plant.
- **Phellem (Cork)**: The phellem is the outer layer produced by the phellogen. It serves as a protective barrier against environmental factors such as pathogens and water loss.

### Step 3: Relating to Plant Anatomy
- In the context of a dicot stem, the phellogen is located in the outer cortex and is responsible for the production of phellem (cork) on its outer side. This process is part of the secondary growth in plants, where the plant increases in diameter.

### Step 4: Summarizing the Relationship
- In summary, phellogen denotes the cork cambium, which is the meristematic tissue that produces phellem (cork) on one side and can also produce phalloderm (secondary cortical cells) on the inner side.

### Final Answer
- **Phellogen** denotes cork cambium, and **Phellem** denotes cork.

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