Biology / Life

What is life?

In order to understand what is life we should check the basic properties of life:

  • Replication - life forms must replicate in order to increase its numbers and survive.
  • Metabolism - all life forms on earth have metabolism.
  • Organic matter - all life forms on earth are made of organic molecules. This is probably not a must have property.
  • Brain - in order to increase the odds of survival, certain forms of life have brains (like most of the people). Yet this is not a must have property.

How did life started?

The old stories describe the creation of life as a instant work of one or several gods.

Modern biology has more scientific approach - the evolution theory.

The evolution theory was discovered by Charles Darwin. The evolution theory explains the how life developed from the start, by small genetic changes:

  • Mutation: small genetic change that may change the life form metabolism and behavior. Usually mutation does not improve the survival chances of the animal and even reduce it. But sometimes the mutation improves the animal's chances of survival by improving a body property that will help it have more descendants.
  • Natural selection: this is the process of the survival of life forms that fit better to the environment, that have more descendants and the death of the life forms that did not succeed to have many descendants or just got eaten by a predator.

What is the purpose of the brain?

The brain purpose is to maintain body homeostasis.

This means that the body must maintain adequate level of many physiological parameters:

  • Oxygen level
  • Glucose level
  • Water level
  • Salt level
  • Body temperature
  • And many other physiological parameters.

When one or more parameter's level is out of the normal range, we start to feel irritated or bad and the brain initiates an action to correct the stability

  • When oxygen level drops, we stop exercising, breath faster and look for fresh air.
  • When water level drops, we feel thirsty and go to drink.
  • When glucose level drops we feel hungry and look for sweet food.
  • When we feel cold, we ware a coat.
  • When we are in danger, we take action to avoid it.

Best body state is achieved when:

∑{wi (Pi-Popti)2} = 0

when i = 1..Number of parameters

wi is the weight or importance of each parameter.

Pi is the current parameter value.

Popti is the optimal parameter value, which can be a range.

What is thinking?

Thinking is a neural activity aimed to maintain homeostasis - when the brain functions well.

When the thinking process disrupts homeostasis, we usually can say that the subject has a mental disorder or stupid or crazy.

The brain correlates the input data from the eyes, ears, taste, ..

How do we decide what to do?

  • The brain holds a model of the existing world.
  • The brain does estimation of the future.
  • The brain holds another model of the future world that we wish to achieve.
  • The brain calculates the difference between the estimated future and the required future, which is the actions that we should take (if possible).


(Decision making as hyperspace movement.)

What is insanity?

Insanity or madness is a state of brain activity when the brain disrupts body homeostasis, instead of maintaining body homeostasis.

Why do we sleep?

There are several reasons for sleeping:

  • Many animals have an optimal time to look for food and walk outside their home. There are animals that sleep during the night and animals that sleep during the day. Humans are animals that sleep during the day. Since man is a daytime animal, during the decades, people who wondered around during the night got eaten by predators. So in order to survive, many daytime animals will sleep at night.
  • Night time animals sleep during the day. The night is the optimal time for them to look for food. Daytime activity will only waist energy.
  • Metabolic activity during sleep - growth hormone is generated and  tissues are regenerated. So body maintenance is done during sleep.
  • Brain balancing - there is a theory that when we dream the wake time input data is processed. So sleeping is vital for proper brain activity.

Which came first, the egg or the chicken?

This old expression is often said as an example to an unresolved paradox.
If the egg was came first, who laid it?
If the chicken came first, didn't she evolve from the egg?
Every egg was laid by a chicken, who grown from an egg, that was laid by a chicken. Since chicken did not exist eternally, where the first egg / chicken came from?
If you believe that god created the world in seven days, then the answer is very simple - since god created all the living creatures, during the first week, god created the chicken first and then came the egg.
Biology has also simple and more scientific answer. According to Darwin's evolution theory - the egg came first. A 99.9% chicken similar creature laid it.
See evolution.
<Chicken and egg picture>

What is beauty?

Symmetry - beautiful people have symmetric body.

Brain resonance - give examples.

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