The movement is with the reproductive capacity, one of the properties that define the living. At the cellular level, certain movements can be observed with the conventional optical microscope, while others occur at a scale of quasi molecular size and require more sophisticated microscopes. Indeed, specialized structures in the production of movement, such as muscle or myofibril sperm flagellum, are true molecular machines whose dimensions are only slightly higher than those of macromolecules that constitute them.
The mechanochemically basis of cell movements are all based on the use of a nucleotide, adenine tripolyphosphate (ATP) and guano-sine tripolyphosphate (GTP), which controlled hydrolysis provides the energy needed to move. The connection between two phosphates attached to these molecules represents the universal energy source in living.
In this article, we will limit ourselves to the study accessible to direct observation events. After characterizing the magnitude of movements across the living, the main modes of transport at the cellular level will be examined, that is to say, swimming and crawling. This leads us to wonder about the behavioral problems that locomotion reveals: responses to the signals they have an adaptive advantage that could offset their energy cost compared to moving randomly?
What may seem an advantage from an evolutionary perspective remains to be assessed. In this debate, abnormal cell movement mechanisms provide useful lessons
The speed range of the movements observed in the living is very wide. Swimming cells in a liquid medium are moving at speeds between 0.1 and 1 millimeter per second. The migrating cells on a surface is much slower, moving from 0.01 micrometer per second for fibroblast 0.1 micrometer per second for the neutrophil leukocyte blood. Amoeba are able to move much faster than 10 micrometers per second.
Specialized sub cellular structures in motility may produce much more rapid movement. The spread of the beat wave of an eyelash or a Eucharistic flagellum is one millimeter per second, while a muscle or some primitive contractile structures can contract at speeds of the order from 10 to 100 millimeters per second. It is with such performance at the basic structures of a champion sprint can move at a speed of about 10 meters per second, through the coordination of the muscles provided by the nervous system, c is also the case for selected during the development of their ability to run the animals, like the cheetah to catch its prey, or the horse to escape predators. This principle of coordination of actions which can increase performance when assembling basic structures is valid at all scales, from molecules to organisms.
Intracellular movements also occur on a large scale speed. Slow axon transport of the neurons at a rate of about 0.01 microns per second, and the rapid transport of the order of 1 micrometer per second. The movement of chromosomes during phase has an intermediate speed. Some intracellular movements can be much faster, in specialized cells such as melancholias or erythrocytes through which certain animals, such as fish, can rapidly change color to blend with the environment: the movement of charged particles of pigment can are more than 10 micrometers per second. The same goes for the cytoplasmic currents some giant algal cells, up to a size of a few millimeters to several centimeters. Internal cytoplasmic currents amoeba Phys-arum plasm-odium in its shape even faster and can reach a speed of 1 mm per second.
The mechanochemically basis of cell movements are all based on the use of a nucleotide, adenine tripolyphosphate (ATP) and guano-sine tripolyphosphate (GTP), which controlled hydrolysis provides the energy needed to move. The connection between two phosphates attached to these molecules represents the universal energy source in living.
In this article, we will limit ourselves to the study accessible to direct observation events. After characterizing the magnitude of movements across the living, the main modes of transport at the cellular level will be examined, that is to say, swimming and crawling. This leads us to wonder about the behavioral problems that locomotion reveals: responses to the signals they have an adaptive advantage that could offset their energy cost compared to moving randomly?
What may seem an advantage from an evolutionary perspective remains to be assessed. In this debate, abnormal cell movement mechanisms provide useful lessons
- the phenomenon of Speed :
The speed range of the movements observed in the living is very wide. Swimming cells in a liquid medium are moving at speeds between 0.1 and 1 millimeter per second. The migrating cells on a surface is much slower, moving from 0.01 micrometer per second for fibroblast 0.1 micrometer per second for the neutrophil leukocyte blood. Amoeba are able to move much faster than 10 micrometers per second.
Specialized sub cellular structures in motility may produce much more rapid movement. The spread of the beat wave of an eyelash or a Eucharistic flagellum is one millimeter per second, while a muscle or some primitive contractile structures can contract at speeds of the order from 10 to 100 millimeters per second. It is with such performance at the basic structures of a champion sprint can move at a speed of about 10 meters per second, through the coordination of the muscles provided by the nervous system, c is also the case for selected during the development of their ability to run the animals, like the cheetah to catch its prey, or the horse to escape predators. This principle of coordination of actions which can increase performance when assembling basic structures is valid at all scales, from molecules to organisms.
Intracellular movements also occur on a large scale speed. Slow axon transport of the neurons at a rate of about 0.01 microns per second, and the rapid transport of the order of 1 micrometer per second. The movement of chromosomes during phase has an intermediate speed. Some intracellular movements can be much faster, in specialized cells such as melancholias or erythrocytes through which certain animals, such as fish, can rapidly change color to blend with the environment: the movement of charged particles of pigment can are more than 10 micrometers per second. The same goes for the cytoplasmic currents some giant algal cells, up to a size of a few millimeters to several centimeters. Internal cytoplasmic currents amoeba Phys-arum plasm-odium in its shape even faster and can reach a speed of 1 mm per second.
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