Tuesday, October 21, 2014

Metabolism, growth, development and size



  1. Science can help predict plant growth and production (equations, variables: temperature).
  2. Is that why Africans are tall (the high temperature, leading to a high rate of metabolism)?
  3. That's why in hot climates plants grow fast and forests of lush vegetation exist. (Water? Deserts?)
  4. That's why my plants grew noticeably during hot days.
  5. Prediction is amazing for size and development for plants, in agriculture!


  1. Do experiments in balcony on plants.


  • How individuals respond to temperature:
    • impaired function and ultimately death at the upper and lower extremes
    • a functional range between the extremes
    • an optimum within the functional range
  • "For each 10°C rise in temperature the rate of biological enzymatic processes doubles, and thus appears as an exponential curve on a plot of rate against temperature."
  • Temperature affects:
    • rates of growth: increases in mass (linear)
    • rates of development: progression through lifecycle stages (linear)
    • final body size
  • Day-degree: number of days to develop X degrees above development threshold
  • Physiological time: a combination of time and temperature required for an organism to develop
  • "Together, the rates of growth and development determine the final size of an organism."
  • "For a given rate of growth, a faster rate of development will lead to smaller final size."
  • Temperature-size rule:
    • Development increases more rapidly with temperature than does growth
    • Thus final size decreases with rising temperature
  • Effects of temperature on growth, development and size has practical importance for prediction.


The effect of temperature on metabolism is quite interesting.