The ratio between 2-carbon and 3-carbon intermediates having- `NH_(2)` group formed in photosynthetic oxidation cycle is

Options

A. `1 : 1`
B. `2 : 1`
C. `3 :2`
D. `3 : 4`

Answer

To solve the question regarding the ratio between 2-carbon and 3-carbon intermediates with an `NH2` group formed in the photosynthetic oxidation cycle, we can follow these steps:

### Step 1: Identify the 2-carbon and 3-carbon intermediates
- The 2-carbon intermediate mentioned in the context of photosynthesis is glycine, which has the chemical formula `NH2CH2COOH`.
- The 3-carbon intermediate is serine, which has the chemical formula `NH2CH(CH2OH)COOH`.

### Step 2: Understand the conversion process
- During photorespiration, two molecules of glycine (2-carbon) are converted into one molecule of serine (3-carbon).
- This indicates that for every 2 molecules of glycine, we obtain 1 molecule of serine.

### Step 3: Calculate the ratio
- Since 2 molecules of glycine (2-carbon) produce 1 molecule of serine (3-carbon), we can express this as a ratio.
- The ratio of 2-carbon (glycine) to 3-carbon (serine) intermediates is therefore 2:1.

### Step 4: Select the correct option
- Based on the calculated ratio of 2:1, we can conclude that the correct answer to the question is option number 2.

### Final Answer
The ratio between 2-carbon and 3-carbon intermediates having `NH2` group formed in the photosynthetic oxidation cycle is **2:1**.

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