A. Neutral water
Less than 7 is acidic (which has 6 letters, 6< 7)
More than 7 is alkaline (which has more than 7 letters). Alkaline = basic
7 is neutral
The Chondrichthyes are the cartilaginous fishes including the sharks, rays,<span>skates and chimeras. The Osteichthyes are the bony fish. Both of these groups </span>became established during the Devonian Period about 400 million years ago. The Chondrichthyes <span>differ from the Osteichthyes in many respects, including their</span><span>
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Answer:
A. Each organism had a different parent that passed on a set of unique genetic instructions.
Explanation:
Organisms can either be single-celled or multicellular. According to this question, a student collects a sample of water from a pond near her home. She then examines a drop of the water under a microscope and noticed it contains four very differently shaped single-celled organisms.
The single-celled organisms are of different shapes because they are from different parents, which passed on a set of unique genetic instructions via their genes to them. Organisms of the same species from the same parent will possess the same shape because they contain same gene which makes them look and behave similar.
However, in this case, the four different shaped single-celled organisms are of DIFFERENT SPECIES and hence, contain individual unique genes that makes them so
I believe it is behavioural isolation. When there are changes within a certain species, e.g. new birdcalls are formed in certain individuals in a species, "traditional" birds may not like such mating calls and only choose to mate with the more common birdcalls from majority of the birds. There are also some birds that may like the new birdcalls, and choose to mate with birds with those birdcalls. They become genetically isolated as they continue such behavior. Eventually, through genetic drift and other mutations, different species form from a single specie.
Hope this helps! :)