Proteins play key roles in olfaction. One kind of protein, called ___________, attaches itself to hydrophobic odorant molecules
so that they may dissolve in watery mucous. A second class of proteins, to which odorant molecules become bound and initiate transduction, are coded by the largest family of genes in mammals and are called ___________ . Group of answer choices
The correct answer is "Odorant-binding proteins (OBPs); Olfactory receptors (ORs)".
Explanation:
Odorant-binding proteins (OBPs) are low-molecular soluble molecules that are secreted in high amounts in the nasal mucus layer. The precise biological activity of OBPs remains unclear, however, its solubility and ability to attach to hydrophobic odorant molecules suggest that they acts as carriers. A second class of proteins called olfactory receptors (ORs), act at the genetic level by initiating transduction once odorant molecules attach to them. ORs are coded by the largest family of genes, which include more than 100 genes and pseudogenes that represent around 3% of the genome.
So where then did all the carbon that living organisms are built of come from? It turns out that most of the carbon we use today came from a collision with another smallish planet about 4.4 billion years ago.
The regular sequence of growth and division that cells undergo is known as the cell cycle. During the cell cycle, a cell grows, prepares for division, and divides into two new cells, which are called “daughter cells.” Each of the daughter cells then begins the cell cycle again.
