} allie lim
Tuesday, January 26, 2010 @ 8:10 PM
Living things, in terms of biology,is a characteristic which distinguishes active organisms from inorganic matters, including capacity for growth, functional activity and the continual change preceding death.
For somethings, it is quite difficult to say that if it is a living thing or not. But, with the help or definitions of this eight characteristics, we will be able to easily tell if it is a living thing or not, with existing evidence.
The eight characteristics are movement, excretion, respiration, irritability, growth, reproduction, adaptability and nutrition.
IS HUMAN HEART A LIVING THING OR NOT?
The answer is yes, it is a living thing. It matches with some of the eight characteristics.
Movement: The heart have muscles to pump blood around the body. There is electric energy which stimulates the heart occurs in the sinoatrial node. Sinoatrial node is the impulse-generating tissue located in the right atrium. It is a group of cells modified as cardiac myocytes,like all muscle cells, have refractory periods,controlling the heart rate.
Growth and reproduction: As learn in science, cells do reproduce in certain methods. In this case, for myocytes, it is the fusing of myoblast where there are mutiple of nuclei. They grow uncontrollably.
Nutrition: Some of the key proteins are important for cell adhesion between myocytes and some are involved in adhesion-dependent cell-to-cell signal transduction that allows for a cascade of cell fusion events.
Here are some pictures for further understanding:
this is a real heart!!! its inside???
this is a sinoatrial node . Even deeper???
myocytes, the cells
In conclusion, human heart is a living thing.
done by : allie(1):D
resources:wikepedia- human heart
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