I believe it is class, because species are divided into different classes, but families, for example: there's the cat family, and there's the dog family. classes: the carnivores, herbivores, omnivores OR mammals, egg laying, or hermaphrodites
Through natural selection it happened over many generations and it was gradual, not a sudden change in the founder species. One bird was randomly born with a fatter beak and so could eat a seed that was harder to crack, this meant he lived longer than the other birds or was fitter, so bred more and so more of the offspring had this slightly larger beak. This continued and the birds moved to the islands with their ideal seed and kept getting fatter beaks etc until they were no longer the same species (this is when they can't breed to produce fertile offspring).
The products of the digestive system are actually tied directly to the circulatory system in that the organs of the digestive system are used to turn ingested food into products that can be absorbed by the blood and then carried to other organs for use as energy or other functions.There are also several links between the digestive system and the respiratory system in that there are organs and muscles that serve both, for example the diaphragm which works to force air into and out of the lungs as well as to force waste products out of the digestive system.<span>All of the systems have to work together as well, without the intake of oxygen and exhalation of carbon dioxide, the function of the digestive system would grind to a halt. Without the production of glycogen and other things necessary for muscular function, produced by the digestive system and then distributed by the circulatory system, all three functions would cease.</span>
There are three phases of stem cells mitosis, gene expression, and differentiation.
<h3 /><h3>What are stem cells?</h3>
Stem cells that are totipotent or omnipotent. programmable stem cells. Multiple-potency stem cells, stem cells with oligopotency, the body's building blocks are stem cells, which are cells that give rise to all other cells with specific roles.
Daughter cells are created when stem cells divide properly in the body or a lab to create additional cells. Most stem cells are found in the bone marrow.
They divide at this stage to produce new blood cells, Once fully developed, blood cells leave the bone marrow and travel into circulation.
Therefore stem cells develop into different cells through differentiation.
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