â¢ The cell cycle is a series of events that takes. place from one cell division to the next. â¢ The time is takes to complete a cell cycle is. not the same in all cells.
A neuron is a nerve cell. The brain is made up of approximately 100 billion neurons. Neurons are similar to other cells in the body in some ways such as: Neurons are surrounded by a membrane. Neurons have a nucleus that contains genes. Neurons contain cytoplasm, mitochondria and other organelles.
The human brain contains approximately 400,000 to 600,000 dopaminergic neurons and thus make up less than 1% of the total number of brain neurons.There are nine dopamine-containing neuronal cell groups in the mammalian brain, each with distinct cellular properties.reater than 70% of all dopaminergic neurons are located in the substantia nigra (see Nigral dopaminergic Cell). Axons of dopaminergic neurons project to the brain by using one of three pathways: the mesostriatal, mesolimbic and mesocortical.