Some ways in which communicable diseases spread are by: physical contact with an infected person, such as through touch (staphylococcus), sexual intercourse (gonorrhea, HIV), fecal/oral transmission (hepatitis A), or droplets (influenza, TB) travel through the air, such as tuberculosis or measles.
The red-green color blindness is a recessive X-linked trait. The females are not affected unless both the X chromosomes have the affected allele. Mostly, the females are the carriers, and the males are affected as they have only one X chromosome. In the given pedigree, the father of Irene have the normal allele, while her mother is a carrier. However, Irene is neither a carrier nor affected. This means that she carries normal alleles on both X chromosomes. Hence, her allele combination is 
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B) the less porous, the less permeable
Porous means "full of holes."
Permeable means "stuff can go through it."
The more porous something is, the more permeable it is.
The longest phase of mitosis is prophase. Because the nuclear membrane disappears, Nucleolus disintegrates, and the DNA condensed to form chromosomes (each chromosome is composed of sister chromatids attached around centromere.)
<span>Both pine trees and ferns have the ability to make their own food via photosynthesis. They are both able to convert water and carbon dioxide into oxygen and sugars. Based on the concept of domains they are both classified under Eukaryota. </span>
