As the star runs out of nuclear fuel, some of its mass flows into its core. Eventually, the core is so heavy that it cannot withstand its own gravitational force. The core collapses, which results in the giant explosion of a supernova. The sun is a single star, but it does not have enough mass to become a supernova.
A city needs power plants to support just about everything in it, just as a cell needs the mitochondria to support the cell in doing it's job.
It is B, I am pretty sure
The correct answer is: B. In sexual reproduction, individuals transmit half of their nuclear genes to each of their offspring.
The main difference between sexual and asexual reproduction is that in sexual reproduction genetic material from two parents is combined, while in asexual reproduction produced offspring is genetically identical to the one parent. So, advantage of sexual reproduction is that produced unique organisms contribute to genetic diversity (variation is formed). But, comparing to asexual reproduction, sexual reproduction requires more energy and lasts longer.
Asexual reproduction is found in lower organisms and can be in different forms: budding, vegetative reproduction, fragmentation, spore formation.
