Green algae usually have a rigid cell wall made of an inner layer of ____and an outer layer of_____.

Options

A. cellulose,cellulose
B. pectose,pectose
C. pectose,cellulose
D. cellulose,pectose

Explanation

To answer the question about the composition of the rigid cell wall in green algae, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organism**: Recognize that we are discussing green algae, which belong to the group known as Chlorophyceae.

2. **Understand Cell Wall Composition**: The cell wall of green algae is known to be rigid. This rigidity is primarily due to the presence of specific substances.

3. **Determine the Inner Layer**: The inner layer of the cell wall in green algae is made of **cellulose**. Cellulose is a polysaccharide that provides structural support.

4. **Determine the Outer Layer**: The outer layer of the cell wall is composed of **pectose**. Pectose is another type of polysaccharide that helps in maintaining the integrity of the cell wall.

5. **Formulate the Answer**: Based on the information gathered, we can conclude that the rigid cell wall of green algae is made of an inner layer of **cellulose** and an outer layer of **pectose**.

### Final Answer:
The inner layer is **cellulose** and the outer layer is **pectose**.

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