I think the correct answer would be A. The yolk sac becomes the placenta. It is membranous sac that is attached to the embryo. It provides all the nutrition and the blood cells needed by the embryo. It is also called the umbilical vesicle.
Structurally, DNA and RNA are nearly identical. However, there are three fundamental differences that account for the very different functions of the two molecules. RNA has a ribose sugar instead of deoxyribose sugar like DNA.
Answer:The seminal vesicles produce mucus to neutralize the acidic environment of the vagina.
Explanation:
The seminal vesicles is found in male reproductive system which produces mucus that is alkaline in order to protect the sperm from the acidic environment of the female vagina . This also contain sugar to nourish the sperm.
The vargina is the outer opening of female reproductive system that receives the sperm. It is acidic in nature because it discharge fluids that contain liquid, cells and bacteria that lubricate and protect it.
C earth’s population will increase quickly