What causes sickle-cell anemia? what causes color blindness? what is a disorder for very thick, sticky mucus that builds up in breathing and in the pancreas? what is a description for down syndrome?

1.Sickle cell anemia is a disorder of the blood caused by an inherited abnormalhemoglobin (the oxygen-carrying protein within the red blood cells).

2.Color blindness is a genetic condition caused by a difference in how one or more of the light-sensitivecells found in the retina of the eye respond to certain colors.

3.Cystic fibrosis is an inherited disease characterized by the buildup of thick, sticky mucus that can damage many of the body's organs.

4.The most common form of Down syndrome is known as trisomy 21, a condition where individuals have 47 chromosomes in each cell instead of 46. 

Stimulants speed up the central nervous system.