All energy sources have some impact on our environment. Fossil fuels—coal, oil, and natural gas—do substantially more harm than renewable energy sources by most measures, including air and water pollution, damage to public health, wildlife and habitat loss, water use, land use, and global warming emissions.
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During transcription, only one strand of DNA is usually copied. This is called the template strand, and the RNA molecules produced are single-stranded messenger RNAs (mRNAs). The DNA strand that would correspond to the mRNA is called the coding or sense strand
Explanation:
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A lot of factors cause genetic variation in a population. The root of all genetic variation is mutations, which occur randomly.
A lot of genetic variation in fact results during meiosis, the process by which gametes (sex/reproductive cells) are formed. The 3 main ways are crossing over, independent assortment of chromosomes, and random fertilization. Crossing over occurs during Prophase I of meiosis, in which genetic material is exchanged between nonsister chromatids of homologous chromosomes. Independent assortment refers to the following: When cells divide during meiosis, homologous chromosomes are randomly distributed during anaphase I, separating and segregating independently of each other. Random fertilization is where any sperm can fertilize any egg cell. The many combinations of eggs and sperms mean variation.
Another source of genetic variation include gene flow. Gene flow is where populations have their members enter other populations (migration), influencing the gene pool of populations. This source is more controversial, however.
Random mating can also increase genetic variation.
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A nucleotide is made up of a sugar molecule.
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They perform checkpoints and regulate/control the cell cycle.
Explanation:
Cyclin/CDK complexes are known to regulate both mitotic and meiotic cell cycles. Some processes are shared by both forms of cell division, however the process known as meiosis differs in terms of its features and needs. Following two rounds of cell division in succession, meiosis is characterized by the replication of DNA.
