Which of the following act as secondary messenger ?

Options

A. DG
B. `IP_3`
C. cAMP
D. All of these

Answer

To determine which of the following act as secondary messengers, we can follow these steps:

### Step 1: Understand the Definition of Secondary Messengers
Secondary messengers are intracellular signaling molecules that are released by cells in response to extracellular signaling molecules (first messengers). They play a crucial role in transmitting signals from outside the cell to elicit physiological changes within the cell.

### Step 2: Identify the Role of Secondary Messengers
These secondary messengers are responsible for triggering various physiological changes at the cellular level, such as:
- Proliferation (cell growth)
- Differentiation (development of cells into specific types)
- Migration (movement of cells)
- Survival (cell viability)
- Apoptosis (programmed cell death)
- Depolarization (change in cell membrane potential)

### Step 3: List Common Examples of Secondary Messengers
Some major examples of secondary messengers include:
- Cyclic AMP (cAMP)
- Cyclic GMP (cGMP)
- Inositol triphosphate (IP3)
- Diacylglycerol (DAG)
- Calcium ions (Ca²⁺)

### Step 4: Analyze the Given Options
If the question provides options, check if any of them match the examples listed above. For instance, if the options include cAMP, DAG, or IP3, these are all recognized as secondary messengers.

### Conclusion
Based on the understanding of secondary messengers and their examples, you can confidently identify which of the provided options act as secondary messengers.

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