What is the definition of Neuron?
Highly specialized unit cells present within the Nervous tissue are called Neurons.
Most important Sensory neurons are used to transfer information from the sensory receptor cells throughout the body to the brain.
They are also called Nerve Cells that send and receive signals from the brain.
Parts of neuron
Neurons differ in size, shape, and structure depending on their role and location. However, nearly all neurons have three essential parts: a cell body, an axon, and dendrites.
Cell body or Cyton contains a central Nucleus and cytoplasm with qualities such as deeply strained particles called Nissl Granules.
AXON is a single, long, cylindrical process that carries impulses away from the cell body.
Besides, dendrites are short processes arising from the Cyton.
In conclusion, the above structure is known as neuron definition.
How many Neurons are in the Human Brain?
This was a rough figure until Dr. Suzana Herculano-Houzel discovered that calculating the number of neurons within the brain seems very straight forward on the surface of the brain.
Henceforth, the doctor suggested, “Just take a sample of the brain, count the number of neurons in that particular sample and then extrapolate that information to account for the remaining volume of the brain.”
Researchers found another method that involved diffusing the cell membranes.
Consequently, to form a sort of “brain soup” so they could count the number of cell nuclei in that particular sample.
The nuclei of the cells were also discolored to get to know the difference between neurons and glia, helping researchers to further count the cell nuclei that belonged to Neurons.
Thereupon, it was observed that on average the human brain has 86 billion Neurons and this is nearly 14 billion neurons less than the approximation, hence not far from the actual result.
1 BILLION of Neurons carries around 6-kilo calories per day.
Do neurons differ from person to person?
Our brain is a keeper for almost 100 billion neurons that each collect, process, and pass on the information in the form of electrical signals.
But so far, there has not been much information about how the differences in the properties of these cells from person to person play a vital role in human cognitive abilities like intelligence.
Thicker Cortex! Higher IQ
Some proofs had suggested that the size of so-called dendrites, the long branched out protrusions through which each neuron receives signals from thousands of other cells, might play a crucial role.
Especially in the regions of Brain that integrate different types of information, such as the frontal and temporal lobes those brain cells have bigger dendrites.
In these brain regions, the cortex, where most of the neurons are present is also thicker in people with higher IQ.
Theoretical studies additionally predicted that larger dendrites may help cells to initiate electrical signals faster.
Apes Neuron definition
Apes are found in Tropical forests of Western and Central Africa and Southeast Asia.
Apes are differentiated by monkeys on the bases of an absence of Tail and by the presence of the Appendix and they have a much more complex Brain.
Consequently, Gorilla, chimpanzee, bonobo, and orangutan are called greater apes because of their large size and more human-like features.
Also, Gibbons is called “the Lesser Apes”.
Differences between the brain of Humans and Apes
The human brain is about three times as bigger as the brain of our closest living relative, the chimpanzee.
Furthermore, a part of the brain called the cerebral cortex – plays a very important role in memory, attention, awareness, and thought – contains twice as many cells in humans as the same area in chimpanzees.
Neurons are very expensive to carry and therefore they cannot be carried by a large Apes with Large body and in a large quantity.
Cost to carry a Neuron
Cost of the body+ cost of the brain< Energy intake
(body size) (neurons) (from raw diet)
If a person eats 8 hours per day then he can consume 53 Billion Neurons but body size will be 25 kilograms.
The brain weighs only 2% of Body Mass but it needs 25% of Body Energy.
That means 500-kilo calories/day out of 2000 kilocalories/day.
To keep your brain working we need at least this amount of energy.
To increase the body-weight it has to give up Neurons.
|53 billion Neurons||25 kilograms|
|45 billion Neurons||50 kilograms|
|30 billion Neurons||75 kilograms|
|12 billion Neurons||100 kilograms|
|Not viable||150 kilograms|
- Humans on the other hand
|86 billion Neurons||70 kilograms|
QUESTION: All things considered, we have to feed more than 9 hr/day ourselves, which is not humanly possible then how can we get there?
ANSWER: TO GET MORE ENERGY FROM THE SAME AMOUNT OF FOOD( RAW MATERIAL) WITH THE HELP OF COOKING.