A pure substance is any substance on its own. For example, sand is impure for containing lots of different substances. However, diamonds are mostly pure for only containing one type of substance.
Whether a substance is pure or not doesn't relate to a substance's molecular structure, but different molecules in a substance. Water by itself is only H2O, therefore it still pure.
Water is not an element but a compound for containing different elements, however it still pure.
question 19 = all the molecules are different lengths ( last answer)
question 20 = crossing over
1 metaphase
2 telophase
3 anaphase
i believe i can’t really see them
Hemochromatosis i<span>s an inherited genetic disorder wherein there is too much build up of iron in the body. It is a common </span>genetic disorder among Caucasians, although this disorder can also affect the Hispanics and the South Asians. Too much iron in the body can poison and damage the tissues and organs (liver, pancreas to name a few) of the body.
Explanation:
The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.