Nail matrix
nail body
free edge nail
nail root
<span>Nails are hard plates of tightly packed keratinized cells. They are clear and cover the dorsal surface of the last phalanges of fingers and toes. Nails protect the the ends of the fingers, allow us to scratch various parts of our body and help us grasping and manipulating small objects.
</span>The site of nail growth is the nail matrix<span> that is found beneath the nail root. The nail matrix is thick and is only composed of the deeper layer of the epidermis: the stratum basale (or germinativum). The keratinization of the cells of the nail matrix proceeds in the absence of a stratum granulosum and lucidum and this results into formation of a of a rigid and durable plate. As the nail matrix thus proliferates and differentiates, this hard plate is pushed forward onto the nail bed and the nail grows.</span>
Answer:
Option-C
Explanation:
A pulse-chase experiment which is used to study the cellular process taking place in the cells. This uses the labelled molecule which is incorporated into the cellular pathway and then the unlabeled molecules are used over time to determine how much time is required by the unlabeled molecule to replace the labelled molecule.
In the given question, the pancreatic cell which secretes the digestive enzyme known as the acinar cell is labelled with the leucine and then used unlabeled leucine.
When observed after three hours, the black spots will appear on the exterior of the cell as the protein has been synthesised by the ER and now has been secreted from the cell.
Thus, Option-C is the correct answer.