Answer:
Explanation: Scientists attempt to order the natural world by grouping and classifying all living organisms. As technologies improve, so have our systems of classification. ... This is the process of “natural selection” and causes the many species of organisms on Earth to change over time
Keratinocytes produce keratin, a type of protein that is a basic component of hair, skin, nails, and helps create an intact barrier.
Answer:
RNA world hypothesis.
Explanation:
RNA is present as the genetic material in some viruses only. RNA is produced from the template DNA by the process of transcription and helps in the protein gene expression.
According to RNA world hypothesis, RNA is considered to be the first genetic material as it has the ability to store the genetic material. The oxyribose sugar makes the RNA more reactive than the DNA molecule. The RNA also has the ability to work enzyme known as ribozyme. Hence, RNA has the ability to store the information and acts as catalyst.
Thus, the answer is RNA world hypothesis.