# 6. Robustness in biological circuits¶

**Design principles**

The on-delay of the C1-FFL is robust to changes in the ratio of the Hill activation constants, \(\kappa\), in the regime when \(\kappa\) is order one or greater.

Exact adaptation, such as that displayed by the chemotaxis circuit in

*E. coli*, can be achieved through integral feedback.

**Techniques**

Michaelis-Menten kinetics to model enzyme dynamics.

**Concepts**

Robustness.

Exact adaptation.

```
[1]:
```

```
import numpy as np
import scipy.integrate
import biocircuits
import bokeh.io
import bokeh.plotting
import panel as pn
pn.extension()
bokeh.io.output_notebook()
```