A closed system is a system that makes no physical or chemical exchanges with its environment. Of these systems provided as choices (tree, human, clock, car), only a clock does not make exchanges with the environment, except for energy.
Therefore, of that list, only a clock would be a closed system.
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The monomer units of the carbohydrates vary in their total numbers extensively. Moreover, positions of the carbonyl groups along with the orientation of the hydroxyl groups also vary in the carbohydrates' monomers. The presence of any modification is also variable.
On the other hand, the nucleic acids have only 4 monomeric units. The linkages between the nucleic acid residues have less geometry than the glycosidic linkages.
The atmosphere transfers heat energy and moisture across the Earth. Incoming solar radiation (insolation) is redistributed from areas in which there is a surplus of heat (the equator) to areas where there is a heat deficit (the North and South Pole). This is achieved through a series of atmospheric cells: the Hadley cell, the Ferrel cell and the Polar cell (Figure 2). These operate in a similar way to, and indeed interact with, the ocean conveyor.
For example, as the oceans at low latitudes are heated, water evaporates and is transported poleward as water vapour. This warm air eventually cools and subsides. Changes in temperature and CO2 concentrations can lead to: changes in the size of atmospheric cells (in particular, the Hadley cell is susceptible to these alterations); warming in the troposphere; and disproportionately strong warming in Arctic regions. The strong interactions between ocean and atmospheric dynamics, and the significant feedback mechanisms between them, mean that climate researchers must consider these Earth components as interlinked systems. The necessity to assess ocean-atmospheric changes at the global scale has implications for the way in which research is conducted. It is only by integrating palaeo evidence of past changes, with present day monitoring, and projected models,
Answer:
Organelle (oppitional, I don't put this on my paper but you can if you want), cells, tissues,
Explanation:
