Normal red blood cells slide easily through narrow blood vessels. In sickle cell disease, many red blood cells change to a crescent shape like a slender moon. Crescent-shaped blood cells cause blockages in blood vessels. These blockages decrease the transport of oxygen. People with sickle cell disease often have sharp pains due to the lack of oxygen in parts of the body. Some people have one sickle cell gene and one normal gene. They have few defective cells and no symptoms because the sickle cell gene is recessive. How does the human system of reproduction result in people getting one copy of a sickle cell gene and one copy of a normal gene? Describe the process.

The gulf stream is a warm water current that flows away from the equator to northern europe. witch of these does it cause. a. crashes of warm and cool water in the ocean b. colder climates near the equator c. large waves on the cost of europe d. warm climates in northern europe

The molecular weight of carbon dioxide, co2, is 44.00 amu, and the molecular weight of nitrous dioxide, no2, is 46.01 amu, so no2 diffuses co2

Astudent made the lewis dot diagram of a compound as shown. mg is written with two dots shown on its top. an o is written on each side of mg. each o has six dots around it. an arrow is shown from one dot on mg toward the vacant space around the o on the right. another arrow is shown from the other dot on mg toward the vacant space around the o on the left. the title of the art is students lewis dot model. what is the error in the lewis dot diagram? an o atom should transfer all its six electrons to mg because the formula is mgo. both electrons of mg should be transferred to one o atom because the formula is mgo. the electrons should be transferred from each o atom to mg because mg has fewer electrons. the number of dots around mg should be four because it has to transfer two electrons to each o.