Cell Signaling: How Communication Happens in Cells
- Reception: the signal is received at a receptor (it can be on the cell surface, as illustrated below, or inside the cell).
- Transduction: the message is communicated through a series of steps causing a…
- Response: a cellular reaction to the signal
Endocrine System: Two Ways Messages Are Received
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Peptide hormones (most hormones) and amino acids and their derivatives:
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Cannot travel across the cell membrane.
- The receptor is on the cell surface.
- A transduction system (using secondary messengers) conveys the message internally.
- A response occurs.
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Steroid and thyroid hormones:
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Can travel across membranes.
- Steroids slip through the cell membrane because they are lipids.
- The receptor is within the cytoplasm of the cell.
- The hormone/receptor complex goes into the nucleus and initiates protein synthesis.
- The new protein causes a response of some kind.
Steroid and Thyroid Hormones: Detail View