The answer is sex cells or gametes
Answer:
Shadows are made by blocking light. Light rays travel from a source in straight lines. If an opaque (solid) object gets in the way, it stops light rays from traveling through it. This results in an area of darkness appearing behind the object. The dark area is called a shadow
Answer: B. Closed
In a closed circulatory system is the one in which the blood is circulated to all the parts of the body of the organism through vessels of different length and width. In this system the blood is pumped from the heart through blood vessels where it is transported to different organs and cells of the body instead of filling up the body cavity.
I don’t understand either