Shells are considered biotic because they come from living things. Biotic describes something living or use to be living such as plants and animals. So shells are considered biotic because they come from a living organism.
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Gymnosperms are no longer restricted to moist environments, as are ferns and mosses because they have evolved to produce non-flagellated pollens that do not require water or moisture to reach the egg whereas ferns and mosses have flagellated sperm that needs moisture to swim towards the egg.
Another major evolutionary adaption in gymnosperms is the production of seeds instead of spores since seeds contain their own nutrition in the form of endosperm, seeds can travel large distances through wind or animals and can germinate when they find suitable conditions. Seeds can remain dormant for several years whereas spores have a shorter lifespan.
To learn more about endosperm here
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Answer:
The answers are a) Cancer cells treated with the chemical have a lower survival rate than cells that are not treated and d) This chemical will be useful for treating all types of cancer.
Explanation:
Since the research finds that cancer cells have a lower survival rate when exposed to a particular species of fungus. In addition to this new chemical compound could be implemented as a cancer drug.
the first answer as blood needs to be oxygenated to be passes round the body then when its deoxgenated it will return to the heart to be pumped around the body again
Suppose that part of an amino acid sequence of a protein changed from tyrosine-proline-glycine-alanine to tyrosine-histidine-glycine-alanine. This change was most likely caused by a point mutation called a <u>substitution</u>.
<u>Explanation:</u>
Any protein is synthesized by joining a number of amino acids together. This amino acid is placed based on the sequences of the DNA , for every 3 sequence there is an amino acid that is synthesized and therefore it is called as a triplet codon, since there may be many sequence for a single amino acid we call it as degenerate codon.
