Answer:
a prezygotic barrier
Explanation:
Both wild tigers and lions are said to be reproductively isolated.
Reproductive isolation is defined as the existence of barrier between organisms of different species such that they cannot reproduce.
The mechanisms of reproductive isolation varies. While some act to prevent the formation of zygotes (in case of mating) between organisms of different species, some ensures that the resulting zygotes are invalid.
Reproductive isolation mechanisms that act to prevent fertilization and formation of zygotes are referred to as prezygotic mechanisms while those that ensure that invalid zygotes result (in case of successful fertilization) are referred to post zygotic mechanisms.
<em>The natural differences in the ranges of wild tigers and lions ensure that both animals do not mate with each other, let alone results in zygote. This is a form of pre-zygotic reproductive isolation mechanism.</em>
The answer would be B. Atom, star, galaxy, universe.
Explanation: atoms are small cells that make up everything in existence. They're too small to be seen by the naked human eye. Stars are big balls of gas that can be seen at night in the sky. These are second biggest because you can see these with the naked eye, but galaxies you can not. The galaxy holds the earth, all of the other planets, stars, and other things. If the galaxy can hold all of that then clearly it would be bigger than the stars. The universe is what holds our galaxy. There are millions of other galaxies out there in the universe. Ours is just a small one of an infinite number.
I think the <span>coefficient is na2s.
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Answer:
From The School of Biomedical Sciences Wiki. Complementary base pairing is the phenomenon where in DNA guanine always hydrogen bonds to cytosine and adenine always binds to thymine. The bond between guanine and cytosine shares three hydrogen bonds compared to the A-T bond which always shares two hydrogen bonds.