I think the answer is b as in boy.
Airborne is the most common.
Answer:
The movement of proteins and enzymes within a cell is facilitated by intracellular receptors.
Explanation:
Proteins and enzymes (which also are proteins) move inside the cell through intracellular receptors. These receptors are proteins capable of binding other molecules such as proteins and hormones in order to transport them to different cellular locations. Thus, intracellular receptors are key players in signaling pathways that trigger signaling events to regulate a particular function, for example, activating gene expression by transporting proteins to the nucleus.
The organs are known as Vestigial organs. The evolution from land-dwelling animal to the marine animals has led whales as well as dolphins, to lose hind limbs. The pelvic and leg bone serves no purpose in them and just provide the anchorage to muscles
