describe the changes as humans develop to old age (KS2, Yr5)
Know that living organisms stay alive because they reap and maintain their cells
Know that an identical copy of the genome exists in every cell of an organism
Know that living organisms need a constant supply of energy and nutrients to stay alive
Appreciate that the same genetic information is transmitted to all cells in the body during cell division
adventures in time and in space
pass on information
These stories use the metaphor “adventure” to describe the changes that take place in and around an organism during its life. There are two types of changes: those that keep the organism alive (being), which involve the maintenance of molecules and organelles (“parts of cells”) and the like-for-like replacement of cells.
This requires a continual input of energy and nutrients into the cells. This has been described as a “flowing balance”***.
The second type of change involves the production and growth of new cells and tissues, associated with growing and developing (becoming).This also requires a continual input of energy and nutrients into the cells.
This story explores these ideas. Despite the continual changes that take place within an organism, it remains recognisably the same. It has a stable identity. How this happens is only now becoming understood, although it does remain something of a mystery.
The story plants the seed that it is the genetic information in the genome that remains the same. It is copied and passed on to every cell that is made by cell division. Cells use this information to grow and maintain themselves in ways that allow the organism to have a stable identity.
***Some teachers might be interested to know why this is. In terms of thermodynamics, living organisms are open systems that maintain themselves in a highly ordered state, when compared with the external environment.
Organisms stay alive as long as they are able to maintain this ordered state. This requires the active self-maintenance described in this story, which requires the flowing balance of energy and nutrients.
When an organism is no longer alive, its body reaches a thermodynamic equilibrium with its environment.
