One should always learn from past mistakes and avoid them in the future.

the atmosphere, the biosphere, the hydrosphere, and the lithosphere.   are all physical systems is probably

the correct answer is moro reflex. this is usually witnessed in infants normally up to the age of 4-5 months (in some cases maybe more)  

it is caused by a sudden loss of support that makes the baby feel as if he or she is falling or is going to fall and hence the flinging of the arms and crying.