# 2.1 The Alpha Helix

> The Alpha Helix (Module 2: The Weaver). Key concept: i→i+4 hydrogen bonding. Explain the i → i+4 hydrogen bond that holds a helix together, from C=O of residue i to N–H of residue i+4.

The Alpha Helix (Module 2: The Weaver). Key concept: i→i+4 hydrogen bonding. Explain the i → i+4 hydrogen bond that holds a helix together, from C=O of residue i to N–H of residue i+4.

- Explain the i → i+4 hydrogen bond that holds a helix together, from C=O of residue i to N–H of residue i+4
- Recall that one helical turn spans roughly 3.6 residues
- Place helix hydrogen bonds correctly along a sequence

## Links

- [Module 2: The Weaver](https://proteindesign.academy/module/2)
- [2.2 Beta Sheets](https://proteindesign.academy/module/2/2)
- [2.3 Loops, Turns & the Unsung Heroes](https://proteindesign.academy/module/2/3)
- [2.4 Helix Breakers & Structural Disruptors](https://proteindesign.academy/module/2/4)
- [2.5 Backbone Geometry: The Ramachandran Map](https://proteindesign.academy/module/2/5)
- [2.integration Secondary Structure Prediction](https://proteindesign.academy/module/2/integration)
- [The Pattern Master](https://proteindesign.academy/module/2/capstone)