How many of the following are examples of hormones which interact with intracellular receptors ?
( Cortisol, testosterone, estradiol , thyroxine ,insulin , epinephrine )

Options

A. 5
B. 4
C. 6
D. 3

Answer

To determine how many of the given hormones interact with intracellular receptors, we will analyze each hormone one by one.

1. **Cortisol**:
- Cortisol is a glucocorticoid hormone and is classified as a steroid hormone. Steroid hormones typically pass through the cell membrane and bind to intracellular receptors.
- **Conclusion**: Cortisol interacts with intracellular receptors.

2. **Testosterone**:
- Testosterone is an androgen hormone, also classified as a steroid hormone. Like cortisol, it can pass through the cell membrane and bind to its intracellular receptor, which is located in the nucleus.
- **Conclusion**: Testosterone interacts with intracellular receptors.

3. **Estradiol**:
- Estradiol is another steroid hormone (an estrogen) and similarly interacts with intracellular receptors. It can also pass through the cell membrane and bind to receptors inside the cell.
- **Conclusion**: Estradiol interacts with intracellular receptors.

4. **Thyroxine (T4)**:
- Thyroxine is a thyroid hormone and is also known to interact with intracellular receptors. It can enter cells and bind to receptors located in the nucleus.
- **Conclusion**: Thyroxine interacts with intracellular receptors.

5. **Insulin**:
- Insulin is a peptide hormone and does not pass through the cell membrane. Instead, it binds to receptors on the cell membrane, which then triggers a signaling cascade inside the cell.
- **Conclusion**: Insulin does not interact with intracellular receptors.

6. **Epinephrine (Adrenaline)**:
- Epinephrine is also a peptide hormone (catecholamine) and, like insulin, binds to receptors on the cell membrane rather than entering the cell and binding to intracellular receptors.
- **Conclusion**: Epinephrine does not interact with intracellular receptors.

Now, let's summarize the findings:
- Hormones that interact with intracellular receptors: Cortisol, Testosterone, Estradiol, Thyroxine (4 hormones).
- Hormones that do not interact with intracellular receptors: Insulin, Epinephrine (2 hormones).

**Final Answer**: 4 hormones interact with intracellular receptors.

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