Answer:
the nervous system sends instructions to the body about how to respond to stimuli
Explanation:
Your nervous system uses specialized cells called neurons to send signals, or messages, all over your body. These electrical signals travel between your brain, skin, organs, glands and muscles. The messages help you move your limbs and feel sensations, such as pain.
"Sex Cells" or "haploids" are needed in order to add variation in DNA. If there was no "haploids" (which are just cells with 23 Chromosomes), then the female would not need the male for reproduction, basically meaning birth of an identical twin to the mother. The two haploids, the female's ova (Egg) and male's sperm meet, creating a zygote, or a fertilized egg.
This makes sure there is "immediate variation", and it isn't just ten generations of the same "Bob"!
Helium makes very light than hydrogen
