<span>Males and females are attracted to each other in order to ensure the viability and fertility of the offspring, which is also why it is uncommon that males of one species be attracted to females of another. Members of two different species cannot mate and thus cannot produce fertile, viable offspring, unless they are part of different sub-species. But they must be part of the same species.
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The sun is the ultimate source
Answer:
C
Explanation:
It is known as lactation. The suckling action of an infant produces prolactin, which leads to milk production; more suckling leads to more prolactin, which in turn leads to more lactation. This is a positive feedback system as the product (milk) produces more suckling and more hormone. When the child is no longer breast feeding, the prolactin drops off and milk production goes down.
Water would move from outside to the inside of the cell through the semi permeable cell membrane and cause the cell to swell.