The fatty acids are those that have single covalent bonds between every carbon and cannot hold any more hydrogens. they usually are associated with a solid state at room temperature. unsaturated polyunsaturated saturated triglyceride glycerol

Saturated fats have only single bonds.

The  grandmother cell  is a hypothetical  neuronthat represents a complex but specific concept or object.[1]  it activates when a person "sees, hears, or otherwise sensibly discriminates"[2]  a specific entity, such as his or her grandmother. the term was in use at least as early as 1966 amongst staff and students in the department of experimental psychology, university of cambridge, england. a similar concept, that of the  gnostic neuron, was proposed two years later