Answer:
Option (2).
Explanation:
Zygote is formed by the fusion of the male and female gamete during the process of sexual reproduction. The zygote undergoes further development inside the female womb.
The embryonic period starts from the third week after the conception. The important organs and structure development occur during the embryonic period. The formation of three germ layers occur in this period.
Thus, the correct answer is option (2)
<span>The group exposed to a newly created drug that is being tested in an experiment is called the experimental group.
Whenever any new drug is formed, it is first experimented then it comes in pharmacies for use. Experimental groups are given variables,one variable is tested at a time. After that experimental group is compared to control group.</span>
Mutagen is an agent that causes DNA mutations. UVA radiation penetrates deep into the skin and acts as a mutagen. UV light is the most common source of radiation that affects DNA, but it is a weak radiation and it penetrates only the surface cells of your skin.
Answer:do you do
The first line of defense involves which structure(s)?
Explanation:
The answer is D, moist skin surfaces.
Explanation:
Cnidaria and flatworms respirate and extreme through their skin via diffusion.
