Chapter 14
Oscillations, Rhythms and Synchronized
Time Bases: The Key Signatures of Life
David Lloyd
Abstract The dynamic complexity of the living state as evident on viewing cells
microscopically defies immediate comprehension. Experiment and theory now
allows us to approach some of the problems of this organized complexity (and one
that embraces inherent functional purpose) characterizing the phenomenon of life. In
an irreducible whole, and in a not so far from equilibrium open system, for the most
part it works on a low-duty cycle. We can distinguish many types of time-dependent
behaviour: e.g., oscillatory, rhythmic, clock-like timekeeping (and synchronized),
deterministically chaotic, and self-similar or fractal), all simultaneously proceeding
on many time scales. Self-synchronized continuous cultures of yeast represent, until
now, the most characterized example of in vivo elucidation of time structure. The
predominantly oscillatory behavior of network components becomes evident, with
spontaneously synchronized cellular respiration cycles between discrete periods of
increased oxygen consumption (oxidative phase) and decreased oxygen consumption
(reductive phase). This temperature-compensated ultradian ‘clock’ provides coordination, linking temporally partitioned functions by direct feedback loops between the
energetic and redox state of the cell and its growing ultrastructure. This model system
represents a basic framework is proposed as a universal cellular principle whereby
ultradian rhythms are the synchronizing signatures that organize the coherence of
the living state. The current challenge is to devise ever increasingly powerful, but
non-invasive (or minimally perturbing) techniques to investigate the living organism.
Keywords Time-structure · Oscillations · Rhythms · Ultradian · Mitochondria ·
Metabolism · Energetics · Oxygen · Dynamics · Synchrony · Signal-processing
D. Lloyd (B)
School of Biosciences, and of Engineering, Cardiff University, Sir Martin Evans Building, Park
Place, Cathays Park, Cardiff CF10 3AX, Wales, UK
e-mail: lloydd@cardiff.ac.uk
© Springer Nature Switzerland AG 2021
A. Stefanovska and P. V. E. McClintock (eds.), Physics of Biological
Oscillators, Understanding Complex Systems,
https://doi.org/10.1007/978-3-030-59805-1_14
225
Oscillations, Rhythms and Synchronized
Time Bases: The Key Signatures of Life
David Lloyd
Abstract The dynamic complexity of the living state as evident on viewing cells
microscopically defies immediate comprehension. Experiment and theory now
allows us to approach some of the problems of this organized complexity (and one
that embraces inherent functional purpose) characterizing the phenomenon of life. In
an irreducible whole, and in a not so far from equilibrium open system, for the most
part it works on a low-duty cycle. We can distinguish many types of time-dependent
behaviour: e.g., oscillatory, rhythmic, clock-like timekeeping (and synchronized),
deterministically chaotic, and self-similar or fractal), all simultaneously proceeding
on many time scales. Self-synchronized continuous cultures of yeast represent, until
now, the most characterized example of in vivo elucidation of time structure. The
predominantly oscillatory behavior of network components becomes evident, with
spontaneously synchronized cellular respiration cycles between discrete periods of
increased oxygen consumption (oxidative phase) and decreased oxygen consumption
(reductive phase). This temperature-compensated ultradian ‘clock’ provides coordination, linking temporally partitioned functions by direct feedback loops between the
energetic and redox state of the cell and its growing ultrastructure. This model system
represents a basic framework is proposed as a universal cellular principle whereby
ultradian rhythms are the synchronizing signatures that organize the coherence of
the living state. The current challenge is to devise ever increasingly powerful, but
non-invasive (or minimally perturbing) techniques to investigate the living organism.
Keywords Time-structure · Oscillations · Rhythms · Ultradian · Mitochondria ·
Metabolism · Energetics · Oxygen · Dynamics · Synchrony · Signal-processing
D. Lloyd (B)
School of Biosciences, and of Engineering, Cardiff University, Sir Martin Evans Building, Park
Place, Cathays Park, Cardiff CF10 3AX, Wales, UK
e-mail: lloydd@cardiff.ac.uk
© Springer Nature Switzerland AG 2021
A. Stefanovska and P. V. E. McClintock (eds.), Physics of Biological
Oscillators, Understanding Complex Systems,
https://doi.org/10.1007/978-3-030-59805-1_14
225