Answer:
sexual selection
natural selection
Explanation:
Natural selection is an evolutionary mechanism (changes the allele frequency) by favouring traits that are advantageous among others because they increase the survival and reproduction. In the example above, mosquitofish that live in the predator-rich ponds devoloped a trait that help them survive (swimming in short, fast bursts). This adaptation to environment is favourable by natural selection.
Sexual selection refers to the female mosquitofish and the fact that they choose their males (with better reproductive success).
Maybe you could drop a ball?
Answer:
Firstly, the partial pressure of nitrogen (78%) is crucial to breathing purposes. Without this pressure, the lungs will burst and animals cannot survive.
Secondly, nitrogen is required for the formation of amino acids (building blocks of proteins) and other organic compounds that are necessary for the survival of living organisms. Principally, in the atmosphere, nitrogen is present in the form of molecular nitrogen (N2). N2 is fixed by nitrogen-fixing bacteria that form nitrates and nitrites. These molecules are then used in biochemical processes to produce proteins (amino acids) and other organic compounds. In the absence of nitrogen, these processes could become seize of limited significantly thus affecting life overall.
Thirdly, nitrogen and its derivatives act as greenhouse gases that maintain the Earth's temperature within a range that supports life. Yes, the increased abundance of nitrous oxides is not good because of acid rain and other issues, however, still, the presence of nitrogen is important for life on this planet.
Your wording is a bit confusing, but I get what you're trying to say.
Here's what the life cycle of a star looks like.
Stars begin as giant balls of hydrogen colliding together and releasing a ton of energy. This hydrogen will eventually fuse together to form helium, and once all of the hydrogen has become helium, This helium will, after a very long time and under lots and lots of pressure, form carbon. When this happens, it is considered a red giant, and the star becomes bigger and less bright. The star will become less and less bright and eventually start to shrink as all of that carbon turns to heavier elements like iron, turning into a dwarf star that eventually dies out.
(Dwarf stars are still shining are called white dwarf stars, and dead ones are black)
The cool part, though, is that massive stars (those which have a mass of at least 3 times the Sun's) turn into heavy elements so fast that the core collapses almost instantaneously and explodes violently into a ball of fire known as a supernova.
Sometimes the core of the star gets left behind, and either forms a neutron star or, if it has the mass of a massive star, will collapse in on itself and become a black hole.
Answer:
10N to the right
Explanation:
He pushed it to the right and there is no other force against it
