I think the correct answer from the choices listed above is the first option. The circumstances that this condition would manifest would be if the child is a male and its mother has the recessive allele. X-linked recessive inheritance<span> is a mode of </span>inheritance<span> in which a </span>mutation<span> in a </span>gene<span> on the </span>X chromosome<span> causes the phenotype to be expressed in males </span><span>and in females who are homozygous for the gene mutation</span>
The term for the type of key that biologists used in separating<span> groups of organisms that are based on couplets is called taxonomic key. This key is very useful in the identification and classification of a </span>specific organism and it usually has an analytical characteristic.<span> </span>
One
substance, other than the secretions from nerve cells, that is used in cell
communication are hormones.
<span>
To
add, <span>a hormone is any member of a class of signaling
molecules produced by glands in multicellular organisms that are transported by
the circulatory system to target distant organs to regulate physiology and
behaviour.</span></span>
Salt water fish actually drink the salt water, excrete the salt, and are left with unsalted water in their body; they do this because the sea water, through the process of osmosis, draws out water from the body. <span>
When they are placed in fresh water, they continue to drink the water, but since the water is now less saline that the fish, water is no longer being drawn out, and in most cases (especially if the transfer was too quick), will start absorbing water, hence they will typically die. </span>
