The pigment concerned with various photomorphogenetic processes in plant has
(a) Open tetrapyrrolic structure
(b) Absorption spectra different from that of chlorophyll
(c) Positive effects on membrane permeability
(d) All of these

Options

A. Open tetrapyrrolic structure
B. Absorption spectra different from that of chlorophyll
C. Positive effects on membrane permeability
D. All of these

Answer

To solve the question regarding the pigment concerned with various photomorphogenetic processes in plants, we will analyze each option provided:

1. **Understanding Photomorphogenesis**:
- Photomorphogenesis refers to the growth and development of plants in response to light. This process is primarily regulated by photoreceptors, with phytochrome being the key pigment involved.

2. **Analyzing the Options**:
- **Option (a)**: Open tetrapyrrolic structure.
- Phytochrome has a different structure than chlorophyll. Chlorophyll has a porphyrin ring structure, while phytochrome has a linear tetrapyrrole structure. Therefore, this option is not correct.

- **Option (b)**: Absorption spectra different from that of chlorophyll.
- Phytochrome absorbs light in the red and far-red regions of the spectrum, while chlorophyll primarily absorbs blue and red light. Although they have some overlapping absorption, they are not identical. This option is partially correct but does not fully capture the essence of the question.

- **Option (c)**: Positive effects on membrane permeability.
- Phytochrome does have positive effects on membrane permeability, which can influence various physiological processes in the plant. This option is correct.

- **Option (d)**: All of these.
- Since options (a) and (b) are not entirely correct, this option cannot be true.

3. **Conclusion**:
- The most accurate option based on the analysis is (c) Positive effects on membrane permeability.

### Final Answer:
The correct answer is (c) Positive effects on membrane permeability.