Lecture 5 - Chain of command
For an angelic disposition it is necessary to construct an appropriate brain. Our brain's behaviour is determined by how the nerve cells are joined up during development. The nerves have very long processes connected to the body where the nucleus sits. During development, the tips move actively and seek out other nerves and muscle with which to connect. How do the nerves find their way?
Nerves from the eye grow out and connect with the brain so as to give a nicely ordered map. An image from the eye is projected on to the brain. If the nerve is damaged the cells grow back to the same place. In the chick embryo the nerves from the spinal cord can find the correct muscles provided they are not too far away: they follow highways and signposts. Many of the nerves that grow out die - is this a way of selecting only those that make the right connections?
Will the angel be male or female? The brain is female in behaviour unless treated with male hormone.
Can Frankenstein ever predict the effect of genes on the development of the brain? Can he ever decipher the programme for development by looking at the egg? Is It possible that the only way to know how the egg will develop is to see how It develops? It may be unpredictable.
About the 1986 CHRISTMAS LECTURES
In the 1986 CHRISTMAS LECTURES, Professor Lewis Wolpert (1929-2021) explores developmental biology in a series titled 'Frankenstein's Quest'. Quoting the fictional Dr Frankenstein: "After days and nights of incredible labour and fatigue, I succeeded in discovering the cause of generation and life..." These lectures will look at how life really is generated.
All life comes from cells and all the animals we see about us come from just one cell, the fertilized egg. How does the egg give rise to bats and boys, gnats and girls, eyes and arms? The egg divides and gives rise to many cells which move, multiply, change, and communicate, and from these activities animals emerge through embryonic development. Like an imaginary Frankenstein, we will explore what we need to know in order to control development in order to create not a monster, but an angel.