Reproductive isolation. Species refer to the group of organisms which share common morphological features and can interbreed and produce a viable offspring. Thus, the organisms of one species are reproductively isolated from the organisms of other species
Deoxyribonucleic acid (DNA) is the hereditary material that lies within the nucleus of all cells in humans and other living organisms. Most of the DNA is placed within the nucleus and is called nuclear DNA.
A chromosome is made up of two chromatids which are joined by the centromere. The chromatids separate from each other during mitosis to form two new chromosomes. The DNA making up a chromosome is dispersed as chromatin.
Under a microscope, chromatids look like little dots and chromosomes are lines.
<span>Nitrogen and phosphorous are the most prevalent aquatic pollution and contribute heavily to the excessive growth of algae in aquatic environments called algae blooms. The nitrogen from the fertilizers is found in molecules called nitrates which are compounds of both oxygen and nitrogen. Phosphorous helps algae to absorb carbon dioxide. So when the phosphorous levels are high the algae absorbs more carbon dioxide, which allows for faster photosynthesis and faster glucose production which leads to faster growth. Although algae need both nitrogen and phosphorous to grow, when the levels are too high the algae grows faster than the ecosystem can sustain leading to oxygen deprivation for the other aquatic organisms.</span>
<span>The only traits that can be acted upon by natural selection are those that are controlled by ___________________</span>
Sixty-five million years ago, more than three-fourths of all plant and animal species living on Earth becameextinct<span>. This event is known as the </span>K-T<span> mass </span>extinctionbecause it occurred at the boundary between theCretaceous<span> (K) and Tertiary (T) time periods. The most famous group of animals to perish was the dinosaurs.
Hope this helps :)</span>
