Answer:
Main sequence stars fuse hydrogen atoms to form helium atoms in their cores. About 90 percent of the stars in the universe, including the sun, are main sequence stars. These stars can range from about a tenth of the mass of the sun to up to 200 times as massive.
Stars start their lives as clouds of dust and gas. Gravity draws these clouds together. A small protostar forms, powered by the collapsing material. Protostars often form in densely packed clouds of gas and can be challenging to detect.
"Nature doesn't form stars in isolation," Mark Morris, of the University of California at Los Angeles (UCLS), said in a statement. "It forms them in clusters, out of natal clouds that collapse under their own gravity."
Smaller bodies — with less than 0.08 the sun's mass — cannot reach the stage of nuclear fusion at their core. Instead, they become brown dwarfs, stars that never ignite. But if the body has sufficient mass, the collapsing gas and dust burns hotter, eventually reaching temperatures sufficient to fuse hydrogen into helium. The star turns on and becomes a main sequence star, powered by hydrogen fusion. Fusion produces an outward pressure that balances with the inward pressure caused by gravity, stabilizing the star.
How long a main sequence star lives depends on how massive it is. A higher-mass star may have more material, but it burns through it faster due to higher core temperatures caused by greater gravitational forces. While the sun will spend about 10 billion years on the main sequence, a star 10 times as massive will stick around for only 20 million years. A red dwarf, which is half as massive as the sun, can last 80 to 100 billion years, which is far longer than the universe's age of 13.8 billion years. (This long lifetime is one reason red dwarfs are considered to be good sources for planets hosting life, because they are stable for such a long time.)
Explanation:
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Answer:
a) How many genotypes will occur in F2
--The genotypes would be- AA Aa aa BB Bb bb CC Cc cc DD Dd dd EE Ee ee (15 genotypes)
Reason-
This is because, after crossing the parents, the F1 generation would all be Heterozygous dominant since one parent is homozygous dominant, while the other is homozygous recessive.
b) 25% of all F2 genotypes would be recessive across the 5 loci
Reason-
This is because each loci would produce only a 25% chance for a recessive trait, which would results to a general probability of 25% also.
c) Yes i would change my answer in A and B if the parent cross was- AABBCCDDEE X aaBBccDDEE
d) Yes i would change my answer in A and B if the parent cross was- AABBCCDDEE X aabbccddEE
When an electron<span> moves from </span>one atom<span> to </span>another<span>, </span>both atoms become<span> ions.</span>
Answer:
1. Both neutron stars and black holes are the corpses of stars that died in explosions known as supernovas. Black holes form when the most massive stars die and neutron stars form when stars not as large die. They both have a very strong gravitational pull, but a black hole's pull is stronger than a neutron star. Neutron stars <u>will turn into</u> black holes if the force of gravity breaks the resistance of electrons.
2. White dwarfs are degenerate, which means they can compress matter. The material in a white dwarf no longer undergoes fusion reactions, so it is supported only by electron degeneracy pressure. This causes it to be extremely dense, saving space and energy.
3. A light year is the distance light travels in a year while an astronomical unit is the average distance between the earth and the sun.
4. A convection zone transfers energy by radiation and conduction.